Exhibit 5.1

May 12, 2020
Owens Corning
One Owens Corning Parkway
Toledo, Ohio 43659
| Re: | $300,000,000 of 3.875% Senior Notes due 2030 of Owens Corning |
Ladies and Gentlemen:
We are acting as counsel for Owens Corning, a Delaware corporation (the “Company”), in connection with the issuance and sale of $300,000,000 aggregate principal amount of 3.875% Senior Notes due 2030 (the “Notes”), pursuant to the Underwriting Agreement, dated May 7, 2020 (the “Underwriting Agreement”), by and among the Company and BofA Securities, Inc., Citigroup Global Markets Inc., Goldman Sachs & Co. LLC and Wells Fargo Securities, LLC, acting as representatives of the several underwriters named therein (the “Underwriters”). The Notes are to be issued pursuant to an indenture, dated as of June 2, 2009 (the “Base Indenture”), among the Company, the guarantors party thereto and Wells Fargo Bank, National Association, as trustee (the “Trustee”), as amended and supplemented by the twelfth supplemental indenture, dated May 12, 2020 (the “Twelfth Supplemental Indenture”), by and between the Company and the Trustee (the Base Indenture, as so amended and supplemented by the Twelfth Supplemental Indenture, the “Indenture”).
In connection with the opinion expressed herein, we have examined such documents, records and matters of law as we have deemed relevant or necessary for purposes of such opinion. Based on the foregoing, and subject to the further limitations, qualifications and assumptions set forth herein, we are of the opinion that the Notes constitute the valid and binding obligations of the Company.
For purposes of the opinion expressed herein, we have assumed that (i) the Trustee has authorized, executed and delivered the Indenture, (ii) the Notes have been duly authenticated by the Trustee in accordance with the Indenture and (iii) the Indenture is the valid, binding and enforceable obligation of the Trustee.
The opinion expressed herein is limited by bankruptcy, insolvency, reorganization, fraudulent transfer and fraudulent conveyance, voidable preference, moratorium or other similar laws and related regulations and judicial doctrines from time to time in effect relating to or affecting creditors’ rights and remedies generally, and by general equitable principles and public policy considerations, whether such principles and considerations are considered in a proceeding at law or at equity.
