CONTINENTAL BUILDING PRODUCTS, INC. 4,000,000 Shares Common Stock ($0.001 par value) Underwriting Agreement

Exhibit 1.1

CONTINENTAL BUILDING PRODUCTS, INC.

4,000,000 Shares

Common Stock

($0.001 par value)

Underwriting Agreement

New York, New York

September 10, 2015

Credit Suisse Securities (USA) LLC

Eleven Madison Avenue

New York, New York 10010

Ladies and Gentlemen:

LSF8 Gypsum Holdings, L.P., a Delaware limited partnership (the “Selling Stockholder”) proposes to sell to the underwriter named in Schedule I hereto (the “Underwriter”), for whom you (the “Representative”) are acting as representative, 4,000,000 shares of common stock, $0.001 par value (“Common Stock”), of Continental Building Products, Inc., a corporation organized under the laws of Delaware (the “Company”), (said shares to be sold by the Selling Stockholder being hereinafter called the “Underwritten Securities”). The Selling Stockholder also proposes to grant to the Underwriters an option to purchase up to 600,000 additional shares of Common Stock (the “Option Securities”; the Option Securities, together with the Underwritten Securities, being hereinafter called the “Securities”).

In addition, in connection with the offering of the Underwritten Securities, the Company has entered into an agreement with the Selling Stockholder, dated as of September 10, 2015 (the “Stock Purchase Agreement”), pursuant to which the Company has agreed to repurchase from the Selling Stockholder on the Closing Date (as defined herein) shares of Common Stock having an aggregate purchase price of approximately $20 million (the “Concurrent Share Repurchase,” and the shares of Common Stock repurchased by the Company pursuant to the Concurrent Share Repurchase, the “Repurchased Shares”) at a price per share equal to the price per share to the Underwriter set forth in Schedule III hereto, as described in the Disclosure Package and Final Prospectus.

The Concurrent Share Repurchase is conditioned upon the consummation of the offering of the Underwritten Securities pursuant to this Agreement. The closing of the offering of the Underwritten Securities is not contingent on the closing of the Concurrent Share Repurchase.

To the extent there are no additional Underwriters listed on Schedule I other than you, the term Representative as used herein shall mean you, as Underwriter, and the terms Representative and Underwriters shall mean either the singular or plural as the context requires.

Certain terms used herein are defined in Section 20 hereof. Any reference herein to the Registration Statement, the Base Prospectus, any Preliminary Prospectus or the Final Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 that were filed under the Exchange Act on or before the Effective Date of the Registration Statement or the issue date of the Base Prospectus, any Preliminary Prospectus or the Final Prospectus, as the case may be; and any reference herein to the terms “amend,” “amendment” or “supplement” with respect to the Registration Statement, the Base Prospectus, any Preliminary Prospectus or the Final Prospectus shall be deemed to refer to and include the filing of any document under the Exchange Act after the Effective Date of the Registration Statement or the issue date of the Base Prospectus, any Preliminary Prospectus or the Final Prospectus, as the case may be, deemed to be incorporated therein by reference.

This is to confirm the agreement among the Selling Stockholder, the Company and the Underwriters concerning the purchase of the Securities from the Selling Stockholder by the Underwriters.

1. Representations and Warranties.

(i) The Company represents and warrants to, and agrees with, each Underwriter as set forth below in this Section 1.

(a) The Company meets the requirements for the use of Form S-3 under the Act and has prepared and filed with the Commission a registration statement (file number 333-202400) on Form S-3, including the Base Prospectus, for registration under the Act of the offering and sale of the Securities. Such Registration Statement, including any amendments thereto filed prior to the Execution Time, has become effective. The Company may have filed with the Commission, as part of an amendment to the Registration Statement or pursuant to Rule 424(b), one or more preliminary prospectus supplements relating to the Securities, including the Preliminary Prospectus, each of which has previously been furnished to you. The Company will file with the Commission the Final Prospectus relating to the Securities in accordance with Rule 424(b). As filed, such final prospectus supplement shall contain all information required by the Act and the rules thereunder and, except to the extent the Representative shall agree in writing to a modification, shall be in all substantive respects in the form furnished to you prior to the Execution Time or, to the extent not completed at the Execution Time, shall contain only such specific additional information and other changes (beyond that contained in the Base Prospectus and any Preliminary Prospectus) as the Company has advised you, prior to the Execution Time, will be included or made therein. The Registration Statement, at the Execution Time, meets the requirements set forth in Rule 415(a)(1)(x).

(b) On each Effective Date, the Registration Statement did, and when the Final Prospectus is first filed in accordance with Rule 424(b) and on the Closing Date and on any date on which Option Securities are purchased, if such date is not the Closing Date (a “settlement date”), the Final Prospectus (and any supplement thereto) will, comply in all material respects with the applicable requirements of the Act and the Exchange Act and the respective rules thereunder; on each Effective Date and at the

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Execution Time, the Registration Statement did not and will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein not misleading; and on the date of any filing pursuant to Rule 424(b) and on the Closing Date and any settlement date, the Final Prospectus (together with any supplement thereto) will not include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, however, that the Company makes no representations or warranties as to the information contained in or omitted from the Registration Statement or the Final Prospectus (or any supplement thereto) in reliance upon and in conformity with information furnished in writing to the Company by or on behalf of any Underwriter through the Representative specifically for inclusion in the Registration Statement or the Final Prospectus (or any supplement thereto), it being understood and agreed that the only such information furnished by or on behalf of any Underwriter consists of the information described as such in Section 8(c) hereof.

(c) The Disclosure Package does not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from the Disclosure Package based upon and in conformity with written information furnished to the Company by or on behalf of any Underwriter through the Representative specifically for use therein, it being understood and agreed that the only such information furnished by or on behalf of any Underwriter consists of the information described as such in Section 8(c) hereof.

(d)(i) At the earliest time after the filing of the Registration Statement that the Company, the Selling Stockholder or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2)) of the Securities and (ii) as of the Execution Time (with such date being used as the determination date for purposes of this clause (ii)), the Company was not and is not an Ineligible Issuer (as defined in Rule 405), without taking account of any determination by the Commission pursuant to Rule 405 that it is not necessary that the Company be considered an Ineligible Issuer.

(e) From the time of the initial filing of the Registration Statement with the Commission through the Execution Time, the Company has been and is an “emerging growth company,” as defined in Section 2(a) of the Securities Act (an “Emerging Growth Company”).

(f) The Company (i) has not alone engaged in any Testing-the-Waters Communication and (ii) has not authorized anyone to engage in Testing-the-Waters Communications. The Company has not distributed any Written Testing-the-Waters Communications. “Testing-the-Waters Communication” means any oral or written communication with potential investors undertaken in reliance on Section 5(d) of the Securities Act. “Written Testing-the-Waters Communication” means any Testing-the-Waters Communication that is a written communication within the meaning of Rule 405 under the Securities Act.

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(g) Each Issuer Free Writing Prospectus does not include any information that conflicts with the information contained in the Registration Statement, including any prospectus supplement deemed to be a part thereof that has not been superseded or modified. The foregoing sentence does not apply to statements in or omissions from any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Company by or on behalf of any Underwriter through the Representative specifically for use therein, it being understood and agreed that the only such information furnished by or on behalf of any Underwriter consists of the information described as such in Section 8(c) hereof.

(h) Each of the Company and its subsidiaries has been duly incorporated, organized or formed and is validly existing and in good standing under the laws of the jurisdiction in which it is chartered or organized with full corporate or limited liability company power and authority to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Disclosure Package and the Final Prospectus, and is duly qualified to do business as a foreign corporation and is in good standing under the laws of each jurisdiction which requires such qualification, except where the failure to be so qualified or in good standing could not, in the aggregate, reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole (a “Material Adverse Effect”).

(i) The subsidiaries listed on Annex A attached hereto are the only significant subsidiaries of the Company as defined by Rule 1-02 of Regulation S-X.

(j) The Company’s authorized equity capitalization is as set forth in the Disclosure Package and the Final Prospectus; the capital stock of the Company conforms in all material respects to the description thereof contained in the Disclosure Package and the Final Prospectus; the outstanding shares of Common Stock of the Company (including the Securities being sold hereunder by the Selling Stockholder) have been duly and validly authorized and issued and are fully paid and nonassessable; the holders of the outstanding shares of capital stock of the Company are not entitled to preemptive or other rights to subscribe for the Securities; and, except as set forth in the Disclosure Package, the Registration Statement and the Final Prospectus, no options, warrants or other rights to purchase, agreements or other obligations to issue, or rights to convert any obligations into or exchange any securities for, shares of capital stock of or ownership interests in the Company are outstanding.

(k) All the outstanding shares of capital stock or ownership interests of each of the Company’s subsidiaries have been duly and validly authorized and issued and are fully paid and nonassessable, and, except as otherwise set forth in the Disclosure Package, the Registration Statement and the Final Prospectus, all outstanding shares of capital stock or ownership interests of the Company’s subsidiaries are owned by the Company, either directly or through wholly owned subsidiaries, free and clear of any perfected security interest or any other security interests, claims, liens or encumbrances.

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(l) There is no franchise, contract or other document of a character required to be described in, filed as an exhibit to or incorporated by reference in the Disclosure Package, the Final Prospectus or the Registration Statement that is not described, filed or incorporated by reference as required (and the Disclosure Package contains in all material respects the same description of the foregoing matters contained in the Final Prospectus); and the statements in the Disclosure Package and the Final Prospectus under the headings “Material U.S. Federal Tax Considerations for Non-U.S. Holders,” “Certain Relationships and Related Transactions, and Director Independence,” “Business-Environmental Matters” and “Legal Proceedings” insofar as such statements summarize legal matters, agreements, documents or proceedings discussed therein, are, in all material respects, accurate and fair summaries of such legal matters, agreements, documents or proceedings.

(m) This Agreement has been duly authorized, executed and delivered by the Company.

(n) The Stock Purchase Agreement has been duly authorized, executed and delivered by the Company.

(o) The Company is not and, after giving effect to the offering and sale of the Securities, will not be an “investment company” as defined in the Investment Company Act of 1940, as amended.

(p) No consent, approval, authorization, filing with or order of any court or governmental agency or body is required in connection with the transactions contemplated herein and in the Stock Purchase Agreement, except (i) such as have been obtained under the Act, (ii) the approval of the Financial Industry Regulatory Authority, Inc. (“FINRA”), (iii) such as may be required under the blue sky laws of any jurisdiction in which the Securities are offered and sold and (iv) for such consents that, if not obtained, would not have a Material Adverse Effect and as would materially adversely affect the ability of the Underwriters to consummate the transactions contemplated by this Agreement.

(q) None of the sale of the Securities, the consummation of any other of the transactions contemplated herein and in the Stock Purchase Agreement or the fulfillment of the terms hereof or thereof will conflict with, or result in a breach or violation of, or an imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, (i) the charter, by-laws or similar organizational documents of the Company or any of its subsidiaries, (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which the Company or any of its subsidiaries is a party or bound or to which its or their property is subject, or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or any of its subsidiaries or any of its or their properties, except, in the case of clauses (ii) and (iii), as would not have a Material Adverse Effect and as would not materially adversely affect the ability of the Underwriters to consummate the transactions contemplated by this Agreement.

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(r) Except for the Selling Stockholder, no holders of securities of the Company have rights to the registration of such securities under the Registration Statement.

(s) The consolidated historical financial statements and schedules of the Company and its consolidated subsidiaries and the gypsum division of Lafarge North America, Inc. (“North American Gypsum Business”) included or incorporated by reference in the Disclosure Package, the Final Prospectus and the Registration Statement present fairly the respective financial condition, results of operations and cash flows of the Company and the North American Gypsum Business as of the dates and for the periods indicated, comply as to form in all material respects with the applicable accounting requirements of the Act and have been prepared in conformity with generally accepted accounting principles in the United States applied on a consistent basis throughout the periods involved (except as otherwise noted therein). The selected financial data set forth under the caption “Selected Financial Data” in the Disclosure Package, the Final Prospectus and Registration Statement fairly present, on the basis stated in the Disclosure Package, the Final Prospectus and the Registration Statement, the information included therein. The pro forma financial statements included in the Disclosure Package, the Final Prospectus and the Registration Statement under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Description of Pro forma Adjustments for the Unaudited Combined Pro Forma Results of Operations for 2013 and 2012” fairly present, on the basis stated therein, the historical financial information included therein; and the pro forma financial information and the related notes thereto included in the Disclosure Package, the Final Prospectus and the Registration Statement have been prepared in accordance with the Commission’s rules and guidance with respect to pro forma consolidated financial statements and the assumptions used in the preparation of such pro forma consolidated financial information are reasonable and are set forth in each of the Disclosure Package, the Final Prospectus and the Registration Statement.

(t) No action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries or their property is pending or, to the best knowledge of the Company, threatened that (i) would reasonably be expected to have a material adverse effect on the performance of this Agreement or the Stock Purchase Agreement or the consummation of any of the transactions contemplated hereby and thereby or (ii) would reasonably be expected to have a Material Adverse Effect, except as set forth in or contemplated in the Disclosure Package and the Final Prospectus (exclusive of any supplement thereto).

(u) Each of the Company and its subsidiaries owns or leases all such properties as are necessary to the conduct of its operations as presently conducted.

(v) None of the Company or any of its subsidiaries is in violation or default of (i) any provision of its charter or bylaws, (ii) the terms of any indenture, contract, lease,

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mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which it is a party or bound or to which its property is subject, or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or such subsidiary or any of its properties, as applicable, which violation or default would, in the case of clauses (ii) and (iii) above, either individually or in the aggregate with all other violations and defaults referred to in this paragraph (v) (if any), have (A) a Material Adverse Effect or (B) materially impair the ability of the Company to perform its obligations in connection with the transactions contemplated herein.

(w) Ernst & Young LLP, who have certified certain financial statements of the Company and its consolidated subsidiaries and the North American Gypsum Business and delivered their report with respect to the audited consolidated financial statements and schedules included in the Disclosure Package and the Final Prospectus, are independent public accountants with respect to the Company within the meaning of the Act and the applicable published rules and regulations thereunder.

(x) The Company has filed all applicable tax returns that are required to be filed or has requested extensions thereof (except in any case in which the failure to so file would not have a Material Adverse Effect) and has paid all taxes required to be paid by it and any other assessment, fine or penalty levied against it, to the extent that any of the foregoing is due and payable, except for any such assessment, fine or penalty that is currently being contested in good faith or as would not have a Material Adverse Effect.

(y) No labor problem or dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is threatened or imminent, and the Company is not aware of any existing or imminent labor disturbance by the employees of any of its or its subsidiaries’ principal suppliers, contractors or customers, except as would not have a Material Adverse Effect.

(z) The Company and each of its subsidiaries are insured by insurers of recognized financial responsibility (except with respect to liabilities which the Company self-insures) against such losses and risks and in such amounts as are adequate and customary in the businesses in which they are engaged; all material policies of insurance and fidelity or surety bonds insuring the Company or any of its subsidiaries or their respective businesses, assets, employees, officers and directors are in full force and effect; the Company and its subsidiaries are in compliance in all material respects with the terms of such policies and instruments; there are no claims by the Company or any of its subsidiaries under any such policy or instrument as to which any insurance company is denying liability or defending under a reservation of rights clause; none of the Company or any subsidiary has been refused any insurance coverage sought or applied for; and none of the Company or any subsidiary has any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a Material Adverse Effect.

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(aa) No subsidiary of the Company is currently prohibited, directly or indirectly, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s property or assets to the Company or any other subsidiary of the Company, except as described in or contemplated by the Disclosure Package and the Final Prospectus (exclusive of any supplement thereto).

(bb) The Company and its subsidiaries possess all licenses, certificates, permits and other authorizations issued by all applicable authorities necessary to conduct their respective businesses, except for any of the foregoing which, if not obtained, would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect, and none of the Company or any subsidiary has received any notice of proceedings relating to the revocation or modification of any such certificate, authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have a Material Adverse Effect.

(cc) The Company and each of its subsidiaries maintain a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles in the United States and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. The Company and its subsidiaries’ internal controls over financial reporting are effective and the Company and its subsidiaries are not aware of any material weakness in their internal controls over financial reporting.

(dd) The Company and its subsidiaries maintain “disclosure controls and procedures” (as such term is defined in Rule 13a-15(e) under the Exchange Act); such disclosure controls and procedures are effective.

(ee) The Company has not taken, directly or indirectly, any action designed to or that has constituted or that might reasonably be expected to cause or result in, under the Exchange Act or otherwise, the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(ff) The Company and its subsidiaries (i) are in compliance with any and all applicable foreign, federal, state and local laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (“Environmental Laws”), (ii) have received and are in compliance with all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses and (iii) have not received notice of any actual or potential liability under any Environmental Law, except where such non-compliance with Environmental Laws, failure to receive required permits, licenses or other approvals, or liability would not have a Material Adverse

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Effect. Except as set forth in the Disclosure Package, the Registration Statement and the Final Prospectus, none of the Company or its subsidiaries has been named as a “potentially responsible party” under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended.

(gg) Except as would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect, there are no facts, circumstances or conditions that reasonably could give rise to the Company or its subsidiaries incurring costs and liabilities (including, without limitation, any capital or operating expenditures required for clean-up, closure of properties or compliance with Environmental Laws, or any permit, license or approval, any related constraints on operating activities and any potential liabilities to third parties) arising under or relating to Environmental Laws.

(hh) Since the time of formation of the Company, (i) none of the Company or any of its subsidiaries has established, sponsored, maintained, contributed to, or could reasonably be expected to be required to contribute to, a “pension plan” (as defined in Section 3(2) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”)) that is subject to, or could reasonably be expected to be subject to, the minimum funding requirements of Section 412 or 430 of the Internal Revenue Code of 1986, as amended (the “Code”) or that is subject to, or could reasonably be expected to be subject to, Title IV of ERISA, or any “multiemployer plan” (as defined in Section 3(37) of ERISA), and (ii) none of the Company or any of its subsidiaries has incurred, or could reasonably be expected to incur, any liability under Title IV of ERISA. Except as disclosed in writing to the Underwriters, none of the Company or any of its subsidiaries has established, sponsored, maintained, contributed to, or could reasonably be expected to be required to contribute to, any retiree medical or retiree welfare benefits arrangement (other than an arrangement that provides “continuation coverage” (as defined in Section 602 of ERISA or 4980B of the Code) or similar governmental arrangement). Except as could not, individually or in the aggregate, have a Material Adverse Effect, each employee benefit plan which is established, sponsored, maintained, or contributed to by the Company and/or one or more of its subsidiaries, or to which the Company and/or one or more of its subsidiaries could reasonably be expected to be required to contribute, is currently in compliance, and is reasonably expected to remain in compliance with the currently applicable provisions of ERISA, the Code and other laws, including but not limited to, the laws regarding tax qualification standards under the Code. None of the following events has occurred, exists or is reasonably likely to occur: (i) an audit or investigation by the Internal Revenue Service, the U.S. Department of Labor, the Pension Benefit Guaranty Corporation or any other federal or state governmental agency or any foreign regulatory agency with respect to the employment or compensation of employees by the Company or any of its subsidiaries that could have a Material Adverse Effect; (ii) any breach of any contractual obligation, or any violation of law with respect to the employment or compensation of employees by the Company or any of its subsidiaries that could have a Material Adverse Effect; (iii) a material increase in the “accumulated post-retirement benefit obligations” (within the meaning of Statement of Financial Accounting Standards 106), if any, of the Company and its subsidiaries compared to the amount of such obligations, if any, as of the date hereof; and (iv) the filing of a claim by one or more employees or former employees of the Company or any of its subsidiaries related to their employment that could have a Material Adverse Effect.

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(ii) None of the Company or any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is aware of or has taken any action, directly or indirectly, that would result in a violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “FCPA”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA; and the Company, its subsidiaries and, to the knowledge of the Company, its affiliates have conducted their businesses in compliance with the FCPA and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.

(jj) The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements and the money laundering statutes and the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the best knowledge of the Company, threatened.

(kk) None of the Company or any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries (i) is currently subject to any sanctions administered by the United States (including any administered or enforced by the Office of Foreign Assets Control of the U.S. Treasury Department (“OFAC”)) or (ii) will, directly or indirectly, use the proceeds of this offering, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person, in any manner that will result in a violation of any economic sanctions imposed by the United States (including any administered or enforced by OFAC, the U.S. Department of State, or the Bureau of Industry and Security of the U.S. Department of Commerce), the United Nations Security Council, the European Union, or the United Kingdom (including sanctions administered or controlled by Her Majesty’s Treasury) (collectively, “Sanctions” and such persons, “Sanctioned Persons”), by, or that could result in the imposition of Sanctions against, any person (including any person participating in the offering, whether as underwriter, advisor, investor or otherwise).

(ll) None of the Company or its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries, is a person that is, or is 50% or more owned or otherwise controlled by a

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person that is: (i) the subject of any Sanctions; or (ii) located, organized or resident in a country or territory that is, or whose government is, the subject of Sanctions that broadly prohibit dealings with that country or territory (currently, Iran, North Korea, Sudan, Syria and the Crimean region of Russia) (collectively, “Sanctioned Countries” and each, a “Sanctioned Country”).

(mm) Except as has been disclosed to the Underwriters or is not material to the analysis under any Sanctions, neither the Company nor any of its subsidiaries has engaged in any dealings or transactions with or for the benefit of a Sanctioned Person, or with or in a Sanctioned Country, in the preceding 3 years, nor does the Company or any of its subsidiaries have any plans to increase its dealings or transactions with Sanctioned Persons, or with or in Sanctioned Countries.

Any certificate signed by any officer of the Company and delivered to the Representative or counsel for the Underwriters in connection with the offering of the Securities shall be deemed a representation and warranty by the Company, as to matters covered thereby, to each Underwriter.

(ii) The Selling Stockholder represents and warrants to, and agrees with, each Underwriter that:

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Any certificate signed by any authorized representative of the Selling Stockholder and delivered to the Representative or counsel for the Underwriters in connection with the offering of the Securities shall be deemed a representation and warranty by the Selling Stockholder, as to matters covered thereby, to each Underwriter.

2. Purchase and Sale.

(a) Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Selling Stockholder agrees to sell to each Underwriter, and each Underwriter agrees, severally and not jointly, to purchase from the Selling Stockholder, at the purchase price set forth in Schedule III hereto, the amount of Underwritten Securities set forth opposite such Underwriter’s name in Schedule I hereto.

(b) Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Selling Stockholder hereby grants an option to the several Underwriters to purchase, severally and not jointly, up to 600,000 Option Securities at the same purchase price per share as the Underwriters shall pay for the Underwritten Securities, less an amount per share equal to any dividends or distributions declared by the Company and payable on the Underwritten Securities but not payable on the Option Securities. Said option may be exercised in whole or in part at any time on or before the 30th day after the date of the Final Prospectus upon written, electronic or telegraphic notice by the Representative to the Company and such Selling Stockholder setting forth the number of shares of the Option Securities as to which the several Underwriters are exercising the option and the settlement date. The number of Option Securities to be purchased by each Underwriter shall be the same percentage of the total number of shares of the Option Securities to be purchased by the several Underwriters as such Underwriter is purchasing of the Underwritten Securities, subject to such adjustments as you in your absolute discretion shall make to eliminate any fractional shares.

(c) The Selling Stockholder will pay all applicable state transfer taxes, if any, involved in the transfer to the several Underwriters of the Securities to be purchased by them from the Selling Stockholder and the respective Underwriters will pay any additional stock transfer taxes involved in further transfers.

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3. Delivery and Payment. Delivery of and payment for the Underwritten Securities and the Option Securities (if the option provided for in Section 2(b) hereof shall have been exercised on or before the third Business Day immediately preceding the Closing Date) shall be made at 10:00 AM, New York City time, on September 16, 2015, or at such time on such later date not more than three Business Days after the foregoing date as the Representative shall designate, which date and time may be postponed by agreement among the Representative, the Selling Stockholder and the Company or as provided in Section 9 hereof (such date and time of delivery and payment for the Securities being herein called the “Closing Date”). Delivery of the Securities shall be made to the Representative for the respective accounts of the several Underwriters against payment by the several Underwriters through the Representative of the purchase price thereof to or upon the order of the Selling Stockholder by wire transfer payable in same-day funds to an account specified by the Selling Stockholder. Delivery of the Underwritten Securities and the Option Securities shall be made through the facilities of The Depository Trust Company unless the Representative shall otherwise instruct.

If the option provided for in Section 2(b) hereof is exercised after the third Business Day immediately preceding the Closing Date, the Selling Stockholder will deliver the Option Securities to the Representative through the facilities of The Depository Trust Company, unless the Representative shall otherwise instruct, on the date specified by the Representative (which shall be within three Business Days after exercise of said option) for the respective accounts of the several Underwriters, against payment by the several Underwriters through the Representative of the purchase price thereof to or upon the order of the Selling Stockholder by wire transfer payable in same-day funds to an account specified by the Selling Stockholder. If settlement for the Option Securities occurs after the Closing Date, the Company and Selling Stockholder will deliver to the Representative on the settlement date for the Option Securities, and the obligation of the Underwriters to purchase the Option Securities shall be conditioned upon receipt of, supplemental opinions, certificates and letters confirming as of such date the opinions, certificates and letters delivered on the Closing Date pursuant to Section 6 hereof.

4. Offering by Underwriters. It is understood that the several Underwriters propose to offer the Securities for sale to the public as set forth in the Final Prospectus.

5. Agreements.

(i) The Company agrees with the several Underwriters that:

(a) Prior to the termination of the offering of the Securities, the Company will not file any amendment of the Registration Statement or supplement (including the Final Prospectus or any Preliminary Prospectus) to the Base Prospectus unless the Company has furnished you a copy for your review prior to filing and will not file any such proposed amendment or supplement to which you reasonably object in a timely manner. The Company will cause the Final Prospectus, properly completed, and any supplement thereto to be filed in a form reasonably approved by the Representative with the Commission pursuant to the applicable paragraph of Rule 424(b) within the time period prescribed and will provide evidence satisfactory to the Representative of such timely filing. The Company will promptly advise the Representative (i) when the Final Prospectus, and any supplement thereto, shall have been filed (if required) with the

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Commission pursuant to Rule 424(b), (ii) when, prior to termination of the offering of the Securities, any amendment to the Registration Statement shall have been filed or become effective, (iii) of any request by the Commission or its staff for any amendment of the Registration Statement or for any supplement to the Final Prospectus or for any additional information, (iv) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or of any notice objecting to its use or the institution or threatening of any proceeding for that purpose and (v) of the receipt by the Company of any notification with respect to the suspension of the qualification of the Securities for sale in any jurisdiction or the institution or threatening of any proceeding for such purpose. The Company will use its reasonable best efforts to prevent the issuance of any such stop order or the occurrence of any such suspension or objection to the use of the Registration Statement and, upon such issuance, occurrence or notice of objection, to obtain as soon as practicable the withdrawal of such stop order or relief from such occurrence or objection, including, if necessary, by filing an amendment to the Registration Statement or a new registration statement and using its reasonable best efforts to have such amendment or new registration statement declared effective as soon as practicable.

(b) If, at any time prior to the filing of the Final Prospectus pursuant to Rule 424(b), any event occurs as a result of which the Disclosure Package would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made at such time, not misleading, the Company will (i) notify promptly the Representative so that any use of the Disclosure Package may cease until it is amended or supplemented; (ii) amend or supplement the Disclosure Package to correct such statement or omission; and (iii) supply any amendment or supplement to you in such quantities as you may reasonably request.

(c) If, at any time when a prospectus relating to the Securities is required to be delivered under the Act (including in circumstances where such requirement may be satisfied pursuant to Rule 172), any event occurs as a result of which the Final Prospectus as then supplemented would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made or the circumstances then prevailing, not misleading, or if it shall be necessary to amend the Registration Statement, file a new registration statement or supplement the Final Prospectus to comply with the Act or the Exchange Act or the respective rules thereunder, including in connection with use or delivery of the Final Prospectus, the Company promptly will (i) notify the Representative of any such event; (ii) prepare and file with the Commission, subject to the second sentence of paragraph (a) of this Section 5, an amendment or new registration statement or supplement which will correct such statement or omission or effect such compliance; and (iii) use its best efforts to have any amendment to the Registration Statement or new registration statement declared effective as soon as practicable in order to avoid any disruption in use of the Final Prospectus and (iv) supply any supplemented Final Prospectus to you in such quantities as you may reasonably request.

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(d) As soon as practicable, the Company will make generally available to its security holders and to the Representative an earnings statement or statements of the Company and its subsidiaries which will satisfy the provisions of Section 11(a) of the Act and Rule 158.

(e) The Company will furnish to the Representative and counsel for the Underwriters, without charge, signed copies of the Registration Statement (including exhibits thereto) and to each other Underwriter a copy of the Registration Statement (without exhibits thereto) and, so long as delivery of a prospectus by an Underwriter or dealer may be required by the Act (including in circumstances where such requirement may be satisfied pursuant to Rule 172), as many copies of each Preliminary Prospectus, the Final Prospectus and each Issuer Free Writing Prospectus and any supplement thereto as the Representative may reasonably request.

(f) The Company will arrange, if necessary, for the qualification of the Securities for sale under the laws of such jurisdictions as the Representative may reasonably designate and will maintain such qualifications in effect so long as required for the distribution of the Securities; provided that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action that would subject it to service of process in suits, other than those arising out of the offering or sale of the Securities, in any jurisdiction where it is not now so subject.

(g) The Company will not, without the prior written consent of the Representative, offer, sell, contract to sell, pledge, or otherwise dispose of (or enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due to cash settlement or otherwise) by the Company or any affiliate of the Company or any person in privity with the Company or any affiliate of the Company), directly or indirectly, including the filing (or participation in the filing) of a registration statement with the Commission in respect of, or establish or increase a put equivalent position or liquidate or decrease a call equivalent position within the meaning of Section 16 of the Exchange Act, any other shares of Common Stock or any securities convertible into, or exercisable, or exchangeable for, shares of Common Stock; or publicly announce an intention to effect any such transaction, for a period of 60 days after the date of this Agreement, provided, however, that the Company may (i) issue and sell Common Stock pursuant to any employee stock option plan, stock incentive plan, stock ownership plan or dividend reinvestment plan of the Company in effect at the Execution Time, (ii) issue Common Stock issuable upon the conversion of securities or the exercise of warrants outstanding at the Execution Time, (iii) file one or more registration statements on Form S-8, (iv) issue and sell in private placements without registration under the Act up to the number of shares of Common Stock representing 5% of the total number of outstanding shares of Common Stock (or options, warrants, or other securities convertible into or exercisable, or exchangeable for, shares of Common Stock) in connection with bona fide mergers or acquisitions, joint ventures, commercial relationships or other strategic transactions, provided that the acquirer of any such shares of Common Stock (or options, warrants or other securities convertible into or exchangeable for shares of Common Stock) so issued

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pursuant to this subclause (iv) enters into an agreement in the form of Exhibit A hereto with respect to such shares of Common Stock (or options, warrants or other securities convertible into or exercisable, or exchangeable for, shares of Common Stock) for the remainder of the 60-day restricted period, and (v) repurchase Common Stock pursuant to and in accordance the Stock Purchase Agreement.

(h) The Company will not take, directly or indirectly, any action designed to or that would constitute or that might reasonably be expected to cause or result in, under the Exchange Act or otherwise, stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(i) The Company agrees to pay the costs and expenses relating to the following matters: (i) the preparation, printing or reproduction and filing with the Commission of the Registration Statement (including financial statements and exhibits thereto), each Preliminary Prospectus, the Final Prospectus and each Issuer Free Writing Prospectus, and each amendment or supplement to any of them; (ii) the printing (or reproduction) and delivery (including postage, air freight charges and charges for counting and packaging) of such copies of the Registration Statement, each Preliminary Prospectus, the Final Prospectus and each Issuer Free Writing Prospectus, and all amendments or supplements to any of them, as may, in each case, be reasonably requested for use in connection with the offering and sale of the Securities; (iii) the preparation, printing, authentication, issuance and delivery of certificates for the Securities, including any stamp or transfer taxes in connection with the original issuance and sale of the Securities; (iv) the printing (or reproduction) and delivery of this Agreement, any blue sky memorandum and all other agreements or documents printed (or reproduced) and delivered in connection with the offering of the Securities; (v) the registration of the Securities under the Exchange Act and the listing of the Securities on the New York Stock Exchange (“NYSE”); (vi) any registration or qualification of the Securities for offer and sale under the securities or blue sky laws of the several states (including filing fees and the reasonable and documented fees and expenses of counsel for the Underwriters relating to such registration and qualification); (vii) any filings required to be made with FINRA (including filing fees and the reasonable and documented fees and expenses of counsel for the Underwriters relating to such filings), provided that the reasonable fees and expenses of counsel for the Underwriters relating to subclause (vi) and (vii) of this Section 5(i) shall not exceed $25,000; (viii) the transportation and other expenses incurred by or on behalf of Company representatives in connection with presentations to prospective purchasers of the Securities; (ix) the fees and expenses of the Company’s accountants and the fees and expenses of counsel (including local and special counsel) for the Company and the Selling Stockholder; and (x) all other costs and expenses incident to the performance by the Company and the Selling Stockholder of their respective obligations hereunder. The Company shall not, however, except as otherwise set forth in Section 7 or 8 hereof, be required to pay for any of the Underwriters’ expenses (other than those related to qualification under FINRA regulation and state securities or Blue Sky laws described above).

(j) The Company agrees that, unless it has or shall have obtained the prior written consent of the Representative, and each Underwriter, severally and not jointly,

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agrees with the Company that, unless it has or shall have obtained, as the case may be, the prior written consent of the Company, it has not made and will not make any offer relating to the Securities that would constitute an Issuer Free Writing Prospectus or that would otherwise constitute a “free writing prospectus” (as defined in Rule 405) required to be filed by the Company with the Commission or retained by the Company under Rule 433; provided that the prior written consent of the parties hereto shall be deemed to have been given in respect of the Free Writing Prospectuses included in Schedule II hereto. Any such free writing prospectus consented to by the Representative or the Company is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company agrees that (x) it has treated and will treat, as the case may be, each Permitted Free Writing Prospectus as an Issuer Free Writing Prospectus and (y) it has complied and will comply, as the case may be, with the requirements of Rules 164 and 433 applicable to any Permitted Free Writing Prospectus, including in respect of timely filing with the Commission, legending and record keeping.

(k) The Company will notify promptly the Representative if the Company ceases to be an Emerging Growth Company at any time prior to the later of (a) completion of the distribution of the Securities within the meaning of the Securities Act and (b) completion of the 60-day restricted period referred to in Section 5(g) hereof.

(ii) The Selling Stockholder agrees with the several Underwriters that:

6. Conditions to the Obligations of the Underwriters. The obligations of the Underwriters to purchase the Underwritten Securities and the Option Securities, as the case may be, shall be subject to the accuracy of the representations and warranties on the part of the

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Company and the Selling Stockholder contained herein as of the Execution Time, the Closing Date and any settlement date pursuant to Section 3 hereof, to the accuracy of the statements of the Company and the Selling Stockholder made in any opinions, certificates and letters pursuant to the provisions hereof or required to be delivered pursuant to Section 3 hereof, to the performance by the Company and the Selling Stockholder of their respective obligations hereunder and to the following additional conditions as of the Closing Date and any settlement date pursuant to Section 3 hereof:

(a) The Final Prospectus, and any supplement thereto, have been filed in the manner and within the time period required by Rule 424(b); any material required to be filed by the Company pursuant to Rule 433(d) under the Act shall have been filed with the Commission within the applicable time periods prescribed for such filings by Rule 433; and no stop order suspending the effectiveness of the Registration Statement or any notice objecting to its use shall have been issued and no proceedings for that purpose shall have been instituted or threatened.

(b) The Company shall have requested and caused Gibson, Dunn & Crutcher LLP, counsel for the Company, to have furnished to the Representative their opinion and letter, dated the Closing Date and addressed to the Representative, in form and substance satisfactory to the Representative.

(c) The Selling Stockholder shall have requested and caused Gibson, Dunn & Crutcher LLP, counsel for the Selling Stockholder, to have furnished to the Representative their opinion and letter, dated the Closing Date and addressed to the Representative, in form and substance satisfactory to the Representative.

(d) Timothy A. Power, General Counsel of the Company, shall have furnished to the Representative his opinion letter, dated the Closing Date and addressed to the Representative, in form and substance satisfactory to the Representative.

(e) The Representative shall have received from Baker Botts L.L.P., counsel for the Underwriters, such opinion or opinions, dated the Closing Date and addressed to the Representative, with respect to sale of the Securities, the Registration Statement, the Disclosure Package, the Final Prospectus (together with any supplement thereto) and other related matters as the Representative may reasonably require.

(f) The Company shall have furnished to the Representative a certificate of the Company, signed by the Chief Executive Officer and the Chief Financial Officer of the Company, dated the Closing Date, to the effect that the signers of such certificate have carefully examined the Registration Statement, the Disclosure Package, the Final Prospectus and any amendment or supplement thereto and this Agreement and that:

(i) the representations and warranties of the Company in this Agreement are true and correct on and as of the Closing Date with the same effect as if made on the Closing Date and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to the Closing Date;

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(ii) no stop order suspending the effectiveness of the Registration Statement or any notice objecting to its use has been issued and no proceedings for that purpose have been instituted or, to the Company’s knowledge, threatened; and

(iii) since the date of the most recent financial statements included in or incorporated by reference into the Disclosure Package and the Final Prospectus (exclusive of any supplement thereto), there has been no Material Adverse Effect, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Disclosure Package and the Final Prospectus (exclusive of any supplement thereto).

(g) The Selling Stockholder shall have furnished to the Representative a certificate of the Selling Stockholder, signed by an officer of, or other authorized person on behalf of, the general partner of the Selling Stockholder, dated the Closing Date, to the effect that the signer of such certificate has carefully examined the Registration Statement, the Disclosure Package, the Final Prospectus and any amendment or supplement thereto and this Agreement and that the representations and warranties of the Selling Stockholder in this Agreement are true and correct on and as of the Closing Date with the same effect as if made on the Closing Date and the Selling Stockholder has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to the Closing Date.

(h) The Company shall have requested and caused Ernst & Young LLP to have furnished to the Representative, at the Execution Time and at the Closing Date, a letter, dated respectively as of the Execution Time and as of the Closing Date, containing such statements and information as is ordinarily included in accountants’ “comfort letters” to underwriters with respect to the financial disclosure contained in the Registration Statement, the Disclosure Package and the Final Prospectus, in form and substance satisfactory to the Representative.

(i) Subsequent to the Execution Time or, if earlier, the dates as of which information is given in the Registration Statement (exclusive of any amendment thereof) and the Final Prospectus (exclusive of any amendment or supplement thereto), there shall not have been any change, or any development involving a prospective change, in or affecting the condition (financial or otherwise), earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto) the effect of which is, in the sole judgment of the Representative, so material and adverse as to make it impractical or inadvisable to proceed with the offering or delivery of the Securities as contemplated by the Registration Statement (exclusive of any amendment thereof), the Disclosure Package and the Final Prospectus (exclusive of any amendment or supplement thereto).

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(j) Prior to the Closing Date, the Company and the Selling Stockholder shall have furnished to the Representative such further information, certificates and documents as the Representative may reasonably request.

(k) Subsequent to the Execution Time, there shall not have been any decrease in the rating of any of the Company’s debt securities by any “nationally recognized statistical rating organization” (as defined in Section 3(a)(62) of the Exchange Act) or any notice given of any intended or potential decrease in any such rating or of a possible change in any such rating that does not indicate the direction of the possible change.

(l) The Securities shall have been listed and admitted and authorized for trading on the NYSE, and satisfactory evidence of such actions shall have been provided to the Representative.

(m) At the Execution Time, the Company shall have furnished to the Representative a letter substantially in the form of Exhibit A hereto from the Selling Stockholder and each officer and director of the Company named in the Registration Statement addressed to the Representative.

If any of the conditions specified in this Section 6 shall not have been fulfilled when and as provided in this Agreement, or if any of the opinions and certificates mentioned above or elsewhere in this Agreement shall not be reasonably satisfactory in form and substance to the Representative and counsel for the Underwriters, this Agreement and all obligations of the Underwriters hereunder may be canceled at, or at any time prior to, the Closing Date by the Representative. Notice of such cancellation shall be given to the Company and the Selling Stockholder in writing or by telephone or facsimile confirmed in writing.

The documents required to be delivered by this Section 6 shall be delivered at the office of Baker Botts L.L.P., counsel for the Underwriters, at 2001 Ross Avenue, Suite 1100, Dallas, Texas 75201, on the Closing Date.

7. Reimbursement of Underwriters’ Expenses. If the sale of the Securities provided for herein is not consummated because any condition to the obligations of the Underwriters set forth in Section 6 hereof is not satisfied, because of any termination pursuant to Section 10 hereof or because of any refusal, inability or failure on the part of the Company or the Selling Stockholder to perform any agreement herein or comply with any provision hereof other than due primarily to a default by any of the Underwriters, the Company will reimburse the Underwriters severally through the Representative on demand for all reasonable and documented out-of-pocket expenses (including reasonable and documented fees and disbursements of counsel) that shall have been incurred by them in connection with the proposed purchase and sale of the Securities.

8. Indemnification and Contribution.

(a) The Company agrees to indemnify and hold harmless each Underwriter, the directors, officers, employees and agents of each Underwriter and each person who controls any Underwriter within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or

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any of them may become subject under the Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, or in the Base Prospectus, any Preliminary Prospectus or the Final Prospectus, or any Issuer Free Writing Prospectus, or in any amendment thereof or supplement thereto, (ii) with respect to the Registration Statement or in any amendment thereof the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, or (iii) with respect to any Preliminary Prospectus, or the Final Prospectus, or any Issuer Free Writing Prospectus, or in any amendment thereof or supplement thereto, the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which such statements were made, not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by it in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made therein in reliance upon and in conformity with written information furnished to the Company by or on behalf of any Underwriter through the Representative specifically for inclusion therein. This indemnity agreement will be in addition to any liability which the Company may otherwise have.

(b) The Selling Stockholder severally agrees to indemnify and hold harmless the Company, each of its directors, each of its officers who signs the Registration Statement and each Underwriter, the directors, officers, employees and agents of each Underwriter to the same extent as the foregoing indemnity from the Company to each Underwriter, but only with reference to written information furnished to the Company by or on behalf of the Selling Stockholder specifically for inclusion in the documents referred to in the foregoing indemnity. This indemnity agreement will be in addition to any liability which any Selling Stockholder may otherwise have.

(c) Each Underwriter severally and not jointly agrees to indemnify and hold harmless the Company, each of its directors, each of its officers who signs the Registration Statement, and each person who controls the Company within the meaning of either the Act or the Exchange Act, and the Selling Stockholder and each person who controls the Selling Stockholder within the meaning of either the Act or the Exchange Act, in each case, to the same extent as the foregoing indemnity from the Company to each Underwriter, but only with reference to written information relating to such Underwriter furnished to the Company by or on behalf of such Underwriter through the Representative specifically for inclusion in the documents referred to in the foregoing indemnity. This indemnity agreement will be in addition to any liability which any Underwriter may otherwise have. The Company and the Selling Stockholder acknowledge that the statements set forth (i) in the last paragraph of the cover page regarding delivery of the Securities and, under the first, third, ninth and tenth paragraphs under the heading “Underwriting,” (ii) the list of Underwriters and their respective participation in the sale of the Securities, (iii) the sentences related to concessions and

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reallowances and (iv) the paragraph related to stabilization, syndicate covering transactions and penalty bids in the Preliminary Prospectus and the Final Prospectus constitute the only information furnished in writing by or on behalf of the several Underwriters for inclusion in the Preliminary Prospectus, the Final Prospectus or any Issuer Free Writing Prospectus.

(d) Promptly after receipt by an indemnified party under this Section 8 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this Section 8, notify the indemnifying party in writing of the commencement thereof; but the failure to so notify the indemnifying party (i) will not relieve it from liability under paragraph (a), (b) or (c) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a), (b) or (c) above. The indemnifying party shall be entitled to appoint counsel (including local counsel) of the indemnifying party’s choice at the indemnifying party’s expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); provided, however, that such counsel shall be reasonably satisfactory to the indemnified party. Notwithstanding the indemnifying party’s election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel (including local counsel), and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the indemnified party shall have reasonably concluded that the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest, (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party, (iii) the indemnifying party shall not have employed counsel reasonably satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding.

(e) In the event that the indemnity provided in paragraph (a), (b), (c) or (d) of this Section 8 is unavailable to or insufficient to hold harmless an indemnified party for any reason, the Company, the Selling Stockholder and the Underwriters severally agree

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to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending the same) (collectively “Losses”) to which the Company, the Selling Stockholder and one or more of the Underwriters may be subject in such proportion as is appropriate to reflect the relative benefits received by the Company and the Selling Stockholder, on the one hand, and by the Underwriters, on the other, from the offering of the Securities; provided, however, that in no case shall any Underwriter (except as may be provided in any agreement among underwriters relating to the offering of the Securities) be responsible for any amount in excess of the underwriting discount or commission applicable to the Securities purchased by such Underwriter hereunder. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the Company, the Selling Stockholder and the Underwriters severally shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company and the Selling Stockholder, on the one hand, and of the Underwriters, on the other, in connection with the statements or omissions which resulted in such Losses as well as any other relevant equitable considerations. Benefits received by the Company and the Selling Stockholder shall be deemed to be equal to the total net proceeds from the offering (before deducting expenses) received by the Selling Stockholder, and benefits received by the Underwriters shall be deemed to be equal to the difference between (x) the aggregate price to the public received by the Underwriter and (y) the aggregate price paid by the Underwriter to the Selling Stockholder with respect to the Securities purchased under this Agreement. Relative fault shall be determined by reference to, among other things, whether any untrue or any alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information provided by the Company and the Selling Stockholder, on the one hand, or the Underwriters, on the other, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The Company, the Selling Stockholder and the Underwriters agree that it would not be just and equitable if contribution were determined by pro rata allocation or any other method of allocation which does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this paragraph (e), no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. For purposes of this Section 8, each person who controls an Underwriter within the meaning of either the Act or the Exchange Act and each director, officer, employee and agent of an Underwriter shall have the same rights to contribution as such Underwriter, and each person who controls the Company or the Selling Stockholder within the meaning of either the Act or the Exchange Act, each officer of the Company who shall have signed the Registration Statement and each director of the Company shall have the same rights to contribution as the Company or the Selling Stockholder, as applicable, subject in each case to the applicable terms and conditions of this paragraph (e).

(f) The Company and the Selling Stockholder may agree, as among themselves and without limiting the rights of the Underwriters under this Agreement, as to the respective amounts of such liability for which they each shall be responsible.

9. Reserved.

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10. Termination. This Agreement shall be subject to termination in the absolute discretion of the Representative, by notice given to the Company prior to delivery of and payment for the Securities, if at any time prior to such delivery and payment (i) trading in the Company’s Common Stock shall have been suspended by the Commission or the NYSE or trading in securities generally on the NYSE shall have been suspended or limited or minimum prices shall have been established on such exchange, (ii) a banking moratorium shall have been declared either by Federal or New York State authorities or (iii) there shall have occurred any outbreak or escalation of hostilities, declaration by the United States of a national emergency or war, or other calamity or crisis the effect of which on financial markets is such as to make it, in the sole judgment of the Representative, impractical or inadvisable to proceed with the offering or delivery of the Securities as contemplated by any Preliminary Prospectus or the Final Prospectus (exclusive of any amendment or supplement thereto).

11. Representations and Indemnities to Survive. The respective agreements, representations, warranties, indemnities and other statements of the Company or its officers, of the Selling Stockholder and of the Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of any Underwriter, the Selling Stockholder or the Company or any of the officers, directors, employees, agents or controlling persons referred to in Section 8 hereof, and will survive delivery of and payment for the Securities. The provisions of Sections 7 and 8 hereof shall survive the termination or cancellation of this Agreement.

12. Notices. All communications hereunder will be in writing and effective only on receipt, and, if sent to the Representative, will be mailed or delivered to Credit Suisse Securities USA) LLC, Eleven Madison Avenue, New York, New York 10010-3629, Attention: LCD-IBD; or, if sent to the Company, will be mailed, delivered or telefaxed to Continental Building Products, Inc., fax no. (703)  ###-###-####, and confirmed to it at Continental Building Products, Inc., 12950 Worldgate Drive, Suite 700, Herndon, VA 20170, attention of the Legal Department; or if sent to the Selling Stockholder, will be mailed, delivered or telefaxed and confirmed to it at Hudson Americas LLC, 2711 N. Haskell Avenue, Suite 1800, Dallas, Texas 75204, Attention: Legal Department, fax no. (214)  ###-###-####.

13. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers, directors, employees, agents and controlling persons referred to in Section 8 hereof, and no other person will have any right or obligation hereunder.

14. No fiduciary duty. The Company and the Selling Stockholder hereby acknowledge that (a) the purchase and sale of the Securities pursuant to this Agreement is an arm’s-length commercial transaction between the Selling Stockholder, on the one hand, and the Underwriters and any affiliate through which they may be acting, on the other, (b) the Underwriters are acting as principal and not as an agent or fiduciary of the Company or the Selling Stockholder and (c) the Company’s engagement of the Underwriters in connection with the offering and the process leading up to the offering is as independent contractors and not in any other capacity. Furthermore, the Company and the Selling Stockholder agree that they are solely responsible for making their own respective judgments in connection with the offering (irrespective of whether any of the Underwriters has advised or is currently advising the

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Company or the Selling Stockholder on related or other matters). The Company and the Selling Stockholder agree that they will not claim that the Underwriters have rendered advisory services of any nature or respect, or owe an agency, fiduciary or similar duty to the Company or the Selling Stockholder, in connection with such transaction or the process leading thereto.

15. Integration. This Agreement supersedes all prior agreements and understandings (whether written or oral) between the Company, the Selling Stockholder and the Underwriters, or any of them, with respect to the subject matter hereof.

16. Applicable Law. This Agreement will be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.

17. Waiver of Jury Trial. The Company and the Selling Stockholder hereby irrevocably waive, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

18. Counterparts. This Agreement may be signed in one or more counterparts, each of which shall constitute an original and all of which together shall constitute one and the same agreement.

19. Headings. The section headings used herein are for convenience only and shall not affect the construction hereof.

20. Definitions. The terms that follow, when used in this Agreement, shall have the meanings indicated.

“Act” shall mean the Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder.

“Base Prospectus” shall mean the base prospectus referred to in paragraph 1(i)(a) above contained in the Registration Statement at the Execution Time.

“Business Day” shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in New York City.

“Commission” shall mean the Securities and Exchange Commission.

“Disclosure Package” shall mean (i) the Base Prospectus, (ii) the Preliminary Prospectus as of the Execution Time, (iii) the Issuer Free Writing Prospectuses, if any, identified in Schedule II hereto, (iv) the pricing information identified on Schedule III hereto and (v) any other Free Writing Prospectus that the parties hereto shall hereafter expressly agree in writing to treat as part of the Disclosure Package.

“Effective Date” shall mean each date and time that the Registration Statement and any post-effective amendment or amendments thereto became or becomes effective.

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“Exchange Act” shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder.

“Execution Time” shall mean the date and time that this Agreement is executed and delivered by the parties hereto.

“Final Prospectus” shall mean the prospectus supplement relating to the Securities that was first filed pursuant to Rule 424(b) after the Execution Time, together with the Base Prospectus.

“Free Writing Prospectus” shall mean a free writing prospectus, as defined in Rule 405.

“Issuer Free Writing Prospectus” shall mean an issuer free writing prospectus, as defined in Rule 433.

“Preliminary Prospectus” shall mean any preliminary prospectus supplement to the Base Prospectus referred to in paragraph 1(i)(a) above which is used prior to the filing of the Final Prospectus, together with the Base Prospectus.

“Registration Statement” shall mean the registration statement referred to in paragraph 1(i)(a) above, including exhibits and financial statements and any prospectus supplement relating to the Securities that is filed with the Commission pursuant to Rule 424(b) and deemed part of such registration statement pursuant to Rule 430B, as amended on each Effective Date, as the case may be.

“Rule 158”, “Rule 163”, “Rule 164”, “Rule 172”, “Rule 405”, “Rule 415”, “Rule 424”, “Rule 430B” and “Rule 433” refer to such rules under the Act.

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If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement among the Company, the Selling Stockholder and the Underwriter.

[Signature Page to Underwriting Agreement]

[Signature Page to Underwriting Agreement]

[Signature Page to Underwriting Agreement]

SCHEDULE I

SCHEDULE II

Schedule of Free Writing Prospectuses included in the Disclosure Package

Issuer Free Writing Prospectus dated September 10, 2015.

SCHEDULE III

Pricing Information

$19.85 per share of Common Stock, par value $0.001 per share

ANNEX A

Subsidiaries of Continental Building Products, Inc.

Continental Building Products Operating Company, LLC

Continental Buchanan, LLC

Continental Palatka, LLC

Continental Silver Grove, LLC

Continental Building Products Canada, Inc.

Continental Building Products, Inc.

Public Offering of Common Stock

September 10, 2015

Credit Suisse Securities (USA) LLC

Eleven Madison Avenue

New York, New York 10010

Ladies and Gentlemen:

This letter is being delivered to you in connection with the proposed Underwriting Agreement (the “Underwriting Agreement”), between Continental Building Products, Inc., a Delaware corporation (the “Company”), LSF8 Gypsum Holdings, L.P., a Delaware limited partnership, and each of you as representatives of a group of Underwriters named therein, relating to an underwritten public offering of Common Stock, $0.001 par value (the “Common Stock”), of the Company (the “Offering”).

In order to induce you and the other Underwriters to enter into the Underwriting Agreement, the undersigned will not, without the prior written consent of Credit Suisse Securities (USA) LLC, offer, sell, contract to sell, pledge or otherwise dispose of, (or enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due to cash settlement or otherwise) by the undersigned or any affiliate of the undersigned or any person in privity with the undersigned or any affiliate of the undersigned), directly or indirectly, including the filing (or participation in the filing) of a registration statement with the Securities and Exchange Commission in respect of, or establish or increase a put equivalent position or liquidate or decrease a call equivalent position within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Securities and Exchange Commission promulgated thereunder with respect to, any shares of capital stock of the Company or any securities convertible into, or exercisable or exchangeable for such capital stock, or publicly announce an intention to effect any such transaction, for a period from the date hereof until 60 days after the date of the Underwriting Agreement (the “Lock-Up Period”).¹ Notwithstanding the foregoing, the undersigned may transfer any or all of the shares of Common Stock or other Company securities if the transfer does not trigger any public filing or reporting requirement or obligation or result in any other voluntary or mandatory public disclosure, in each case of a reduction in beneficial ownership, including but not limited to Form 4 of Section 16 of the Securities Exchange Act of 1934, as amended, (other than a filing on a Form 5, Schedule 13D, Schedule 13G or an amendment thereto made after the expiration of the Lock-Up Period) and is (i) by gift, (ii) by will or intestacy, (iii) a disposition to any trust the beneficiaries of which

are the undersigned and/or immediate family members of the undersigned, or in the case of such a trust, to any beneficiaries of the trust, (iv) to an immediate family member of the undersigned or (v) a distribution to partners, members or shareholders of the undersigned, or to any corporation, partnership or other entity that is an affiliate of the undersigned; provided, however, it shall be a condition to the transfer that the transferee of shares agrees in writing to be bound by the same restrictions in place for the undersigned pursuant to this letter for the duration that such restrictions remain in effect at the time of transfer. If the undersigned is an officer or director of the Company, the undersigned further agrees that the foregoing restrictions shall be equally applicable to any issuer-directed shares of Common Stock the undersigned may purchase in the Offering.

If for any reason the Underwriting Agreement shall be terminated prior to the Closing Date (as defined in the Underwriting Agreement), the agreement set forth above shall likewise be terminated. Notwithstanding anything herein to the contrary, if the Closing Date has not occurred prior to the date that is the last date of the Lock-Up Period, this letter shall be of no further force or effect.

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