AMENDMENT NO. 4 Dated as of September 26, 2012 to LOAN AGREEMENT Dated as of June 19, 2006

Exhibit 10.37

EXECUTION COPY

AMENDMENT NO. 4

Dated as of September 26, 2012

to

LOAN AGREEMENT

Dated as of June 19, 2006

THIS AMENDMENT NO. 4 (this “Amendment”) is made as of September 26, 2012 by and among H.B. Fuller Company (the “Company”), the financial institutions listed on the signature pages hereof (the “Lenders”) and JPMorgan Chase Bank, N.A., as Administrative Agent (the “Agent”), under that certain Loan Agreement dated as of June 19, 2006 by and among the Company, the Lenders and the Agent (as amended prior to the date hereof, the “Loan Agreement”). Defined terms used herein and not otherwise defined herein shall have the respective meanings given to them in the Loan Agreement.

WHEREAS, the Company, the Lenders party hereto and the Agent have agreed to amend the Loan Agreement on the terms and conditions set forth herein;

NOW, THEREFORE, in consideration of the premises set forth above, the terms and conditions contained herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Company, the Lenders party hereto and the Agent have agreed to the following amendment to the Loan Agreement.

1. Amendment to Loan Agreement. Subject to the satisfaction of the conditions precedent set forth in Section 2 below, clause (l) of Section 6.04 of the Loan Agreement is hereby amended and restated to read as follows:

(l) any other investment, loan, advance or Guarantee not otherwise permitted by this Section (other than acquisitions, but including investments or capital contributions by the Borrower or any Subsidiary in Joint Ventures) so long as the aggregate amount outstanding of all such investments, loans, advances and Guarantees does not exceed $75,000,000 during the term of this Agreement.

2. Conditions of Effectiveness. The effectiveness of this Amendment is subject to the conditions precedent that the Agent shall have received (i) counterparts of this Amendment duly executed by the Company, the Required Lenders and the Agent and the Consent and Reaffirmation attached hereto duly executed by the Subsidiary Guarantors and (ii) from the Company payment and/or reimbursement of the Agent’s and its affiliates’ fees and reasonable out-of-pocket expenses (including reasonable legal fees and expenses) in connection with this Amendment.

3. Representations and Warranties of the Company. The Company hereby represents and warrants as follows:

(a) This Amendment and the Loan Agreement as amended hereby constitute legal, valid and binding obligations of the Company and are enforceable against the Company in accordance with their terms.

(b) As of the date hereof and giving effect to the terms of this Amendment, (i) there exists no Default or Event of Default and (ii) the representations and warranties contained in Article III of the Loan Agreement, as amended hereby, are true and correct, except for representations and warranties made with reference solely to an earlier date.

4. Reference to and Effect on the Loan Agreement.

(a) Upon the effectiveness of Section 1 hereof, each reference to the Loan Agreement in the Loan Agreement or any other Loan Document shall mean and be a reference to the Loan Agreement as amended hereby.

(b) Except as specifically amended above, the Loan Agreement and all other documents, instruments and agreements executed and/or delivered in connection therewith shall remain in full force and effect and are hereby ratified and confirmed.

(c) The execution, delivery and effectiveness of this Amendment shall not operate as a waiver of any right, power or remedy of the Agent or the Lenders, nor constitute a waiver of any provision of the Loan Agreement or any other documents, instruments and agreements executed and/or delivered in connection therewith.

5. Governing Law. This Amendment shall be governed by and construed in accordance with the laws of the State of New York.

6. Headings. Section headings in this Amendment are included herein for convenience of reference only and shall not constitute a part of this Amendment for any other purpose.

7. Counterparts. This Amendment may be executed by one or more of the parties hereto on any number of separate counterparts, and all of said counterparts taken together shall be deemed to constitute one and the same instrument.

[Signature Pages Follow]

2

IN WITNESS WHEREOF, this Amendment has been duly executed as of the day and year first above written.

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

Signature Page to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006

CONSENT AND REAFFIRMATION

Each of the undersigned hereby acknowledges receipt of a copy of the foregoing Amendment No. 4 to the Loan Agreement dated as of June 19, 2006 (as the same may be amended, restated, supplemented or otherwise modified from time to time, the “Loan Agreement”) by and among H.B. Fuller Company (the “Company”), the financial institutions from time to time party thereto (the “Lenders”) and JPMorgan Chase Bank, N.A., in its individual capacity as a Lender and in its capacity as contractual representative (the “Agent”), which Amendment No. 4 is dated as of September 26, 2012 (the “Amendment”). Capitalized terms used in this Consent and Reaffirmation and not defined herein shall have the meanings given to them in the Loan Agreement. Without in any way establishing a course of dealing by the Agent or any Lender, each of the undersigned consents to the Amendment and reaffirms the terms and conditions of the Subsidiary Guaranty and any other Loan Document executed by it and acknowledges and agrees that such agreement and each and every such Loan Document executed by the undersigned in connection with the Loan Agreement remains in full force and effect and is hereby reaffirmed, ratified and confirmed. All references to the Loan Agreement contained in the above-referenced documents shall be a reference to the Loan Agreement as so modified by the Amendment and as the same may from time to time hereafter be amended, modified or restated.

Dated: September 26, 2012

Signature Page to Consent and Reaffirmation to Amendment No. 4

H.B. Fuller Company

Loan Agreement dated as of June 19, 2006