Exhibit 4.6


 


EXECUTION VERSION


 


Fifth Supplemental Indenture


 


Fifth
SUPPLEMENTAL INDENTURE, dated as of November 16, 2018 (this “Supplemental Indenture”), among the Subsidiaries
listed on Schedule 1 hereto (the “New Subsidiary Guarantors” and each,
a “New Subsidiary Guarantor”), NCI Building Systems, Inc., a Delaware corporation, as successor to the
Predecessor Company (as defined below) (the “Successor Company”), each other then-existing Subsidiary Guarantor
under the Indenture referred to below (the “Existing Guarantors” and, together with the New Subsidiary Guarantors,
the “Subsidiary Guarantors”), and Wilmington Trust, National Association, as Trustee under the Indenture referred
to below (the “Trustee”).


 


WITNESSETH:


 


WHEREAS, Ply Gem Midco, LLC (formerly known
as Ply Gem Midco, Inc., and formerly known as Pisces Midco, Inc.), a Delaware limited liability company (the “Predecessor
Company”), any Existing Guarantors and the Trustee have heretofore become parties to an Indenture, dated as of April
12, 2018 (as supplemented by the First Supplemental Indenture, dated as of April 12, 2018, the Second Supplemental Indenture, dated
as of April 12, 2018, the Third Supplemental Indenture, dated as of April 13, 2018, and the Fourth Supplemental Indenture, dated
as of October 15, 2018, and as further amended, supplemented, waived or otherwise modified, the “Indenture”),
providing for the issuance of Notes in series;


 


WHEREAS, the Predecessor Company has merged
with and into the Successor Company (the “Merger”), with the Successor Company being the surviving entity;


 


WHEREAS, Article V of the Indenture provides
that the Predecessor Company shall be permitted to merge with or into any Person, provided that upon any such merger such resulting,
surviving, or transferee Person shall expressly assume all the obligations of the Predecessor Company under the Notes and the Indenture
by executing and delivering to the Trustee a supplemental indenture or one or more other documents or instruments in form reasonably
satisfactory to the Trustee, and that thereupon the Predecessor Company shall be relieved of all obligations and covenants under
the Indenture;


 


WHEREAS, Section 501(a)(iv) of the Indenture
provides that each Existing Subsidiary Guarantor shall execute and deliver to the Trustee a supplemental indenture or other document
or instrument in form reasonably satisfactory to the Trustee, pursuant to which such Existing Subsidiary Guarantor shall confirm
its Subsidiary Guarantee;


 


WHEREAS, Section 1308 of the Indenture
provides that the Successor Company is required to cause the New Subsidiary Guarantors to execute and deliver to the Trustee a
supplemental indenture pursuant to which the New Subsidiary Guarantors shall guarantee the Successor Company’s Subsidiary
Guaranteed Obligations under the Notes pursuant to a Subsidiary Guarantee on the terms and conditions set forth herein and in Article
XIII of the Indenture;


 




    	 		 



     


    

 


WHEREAS, each New Subsidiary Guarantor desires
to enter into such supplemental indenture for good and valuable consideration, including substantial economic benefit in that the
financial performance and condition of such New Subsidiary Guarantor is dependent on the financial performance and condition of
the Successor Company, the obligations hereunder of which such New Subsidiary Guarantor has guaranteed, and on such New Subsidiary
Guarantor’s access to working capital through the Successor Company’s access to revolving credit borrowings and term
borrowings under the Senior Credit Agreements; and


 


WHEREAS, pursuant to Section 901 of the
Indenture, the parties hereto are authorized to execute and deliver this Supplemental Indenture to amend the Indenture, without
the consent of any Holder.


 


NOW, THEREFORE, in consideration of the foregoing
and for other good and valuable consideration, the receipt of which is hereby acknowledged, the New Subsidiary Guarantors, the
Successor Company, the Existing Guarantors and the Trustee mutually covenant and agree for the benefit of the Holders of the Notes
as follows:


 


1.          Defined
Terms. As used in this Supplemental Indenture, terms defined in the Indenture or in the preamble or recital hereto are used
herein as therein defined. The words “herein,” “hereof” and “hereby” and other words of similar
import used in this Supplemental Indenture refer to this Supplemental Indenture as a whole and not to any particular section hereof.


 


2.          Assumption
of Obligations. In accordance with Article V and Section 901 of the Indenture, the Successor Company hereby expressly assumes
all of the obligations of the Predecessor Company under the Notes and the Indenture and agrees to pay, perform and discharge when
due each and every debt, obligation, covenant and agreement incurred, made or to be paid, performed or discharged by the Predecessor
Company under the Indenture and the Notes. The Successor Company hereby agrees to be bound by all the terms, provisions and conditions
of the Indenture and the Notes and agrees that it shall be the Successor Company (as defined in the Indenture) and shall succeed
to, and be substituted for, and may exercise every right and power of, the Predecessor Company under the Indenture and the Notes
and any references to “Company” in the Indenture, the Notes or other related documents or instruments shall describe
the Successor Company.


 


3.          Affirmation
of Guarantee for Existing Subsidiary Guarantors. Each Existing Subsidiary Guarantor hereby confirms its guarantee of the Subsidiary
Guaranteed Obligations under the Indenture and the Notes on the terms and subject to the conditions set forth in Article XIII of
the Indenture.


 


4.          Agreement
to Guarantee for New Subsidiary Guarantors. Each New Subsidiary Guarantor hereby agrees, jointly and severally with all other
Subsidiary Guarantors and fully and unconditionally, to guarantee the Subsidiary Guaranteed Obligations under the Indenture and
the Notes on the terms and subject to the conditions set forth in Article XIII of the Indenture and to be bound by (and shall be
entitled to the benefits of) all other applicable provisions of the Indenture as a Subsidiary Guarantor.


 




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5.          Termination,
Release and Discharge. Each Subsidiary Guarantor’s Subsidiary Guarantee shall terminate and be of no further force or
effect, and each Subsidiary Guarantor shall be released and discharged from all obligations in respect of such Subsidiary Guarantee,
as and when provided in Section 1303 of the Indenture.


 


6.          Parties.
Nothing in this Supplemental Indenture is intended or shall be construed to give any Person, other than the Holders and the Trustee,
any legal or equitable right, remedy or claim under or in respect of each Subsidiary Guarantor’s Subsidiary Guarantee or
any provision contained herein or in Article XIII of the Indenture.


 


7.          Governing
Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK. THE
TRUSTEE, THE SUCCESSOR COMPANY, ANY OTHER OBLIGOR IN RESPECT OF THE NOTES AND (BY THEIR ACCEPTANCE OF THE NOTES) THE HOLDERS AGREE
TO SUBMIT TO THE JURISDICTION OF ANY UNITED STATES FEDERAL OR STATE COURT LOCATED IN THE BOROUGH OF MANHATTAN, IN THE CITY OF NEW
YORK IN ANY ACTION OR PROCEEDING ARISING OUT OF OR RELATING TO THIS SUPPLEMENTAL INDENTURE.


 


8.          Ratification
of Indenture; Supplemental Indentures Part of Indenture. Except as expressly amended hereby, the Indenture is in all respects
ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect. This Supplemental
Indenture shall form a part of the Indenture for all purposes, and every Holder of Notes heretofore or hereafter authenticated
and delivered shall be bound hereby. The Trustee makes no representation or warranty as to the validity or sufficiency of this
Supplemental Indenture or as to the accuracy of the recitals to this Supplemental Indenture.


 


9.          Counterparts.
The parties hereto may sign one or more copies of this Supplemental Indenture in counterparts, all of which together shall constitute
one and the same agreement.


 


10.         Headings.
The section headings herein are for convenience of reference only and shall not be deemed to alter or affect the meaning or interpretation
of any provisions hereof.


 




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IN WITNESS WHEREOF, the parties hereto have
caused this Supplemental Indenture to be duly executed as of the date first above written.


 


	 	NCI Building SYstems, Inc.
	 	 	 	 
	 	By:	/s/ Todd R. Moore
	 	 	Name: 	Todd R. Moore
	 	 	Title:	Executive Vice President, Chief
	 	 	 	Legal, Risk & Compliance Officer
	 	 	 	and Corporate Secretary


 


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	 	NEW SUBSIDIARY GUARANTORS:
	 	 
	 	NCI Group, Inc.
	 	 	 	 
	 	By:	/s/ Todd R. Moore
	 	 	Name:	Todd R. Moore
	 	 	Title:	Executive Vice President, Chief
	 	 	 	Legal, Risk & Compliance Officer
	 	 	 	and Corporate Secretary
	 	 	 	 
	 	ROBERTSON-CECO II CORPORATION
	 	 	 	 
	 	By:	/s/ Todd R. Moore
	 	 	Name: 	Todd R. Moore
	 	 	Title:	Executive Vice President, Chief
	 	 	 	Legal, Risk & Compliance Officer
	 	 	 	and Corporate Secretary
	 	 	 	 
	 	STEELBUILDING.COM, LLC
	 	 	 	 
	 	By:	/s/ Todd R. Moore
	 	 	Name:	Todd R. Moore
	 	 	Title:	Executive Vice President, General
	 	 	 	Counsel and Secretary
	 	 	 	 
	 	CENTRIA
	 	 	 	 
	 	By:	NCI Group, Inc., its managing partner
	 	 	 	 
	 	By:	/s/ Todd R. Moore
	 	 	Name:	Todd R. Moore
	 	 	Title:	Executive Vice President, Chief
	 	 	 	Legal, Risk & Compliance Officer
	 	 	 	and Corporate Secretary


 


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	 	NEW SUBSIDIARY GUARANTORS (cont’d):
	 	 
	 	Centria, Inc.
	 	 	 	 
	 	By:	/s/ Todd R. Moore
	 	 	Name: 	Todd R. Moore
	 	 	Title:	Executive Vice President, Chief
	 	 	 	Legal, Risk & Compliance Officer
	 	 	 	and Corporate Secretary
	 	 	 	 
	 	CENTRIA SERVICES GROUP, LLC
	 	 	 	 
	 	By:	/s/ Todd R. Moore
	 	 	Name:	Todd R. Moore
	 	 	Title:	Executive Vice President, General
	 	 	 	Counsel and Secretary


 


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	 	EXISTING GUARANTORS:
	 	 
	 	PLY GEM HOLDINGS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:  	Shawn K. Poe
	 	 	Title:	Executive Vice President, Chief Financial Officer, Secretary and Treasurer
	 	 	 	 
	 	PLY GEM INDUSTRIES, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Executive Vice President, Chief Financial Officer and Secretary
	 	 	 	 
	 	ALENCO BUILDING PRODUCTS MANAGEMENT, L.L.C.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	ALENCO EXTRUSION GA, L.L.C.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	ALENCO EXTRUSION MANAGEMENT, L.L.C.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name: 	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	ALENCO HOLDING CORPORATION
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	ALENCO INTERESTS, L.L.C.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	ALENCO TRANS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	ALENCO WINDOW GA, L.L.C.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name: 	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	ALUMINUM SCRAP RECYCLE, L.L.C.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	AWC ARIZONA, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	AWC HOLDING COMPANY
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	FOUNDATION LABS BY PLY GEM, LLC
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name: 	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	GLAZING INDUSTRIES MANAGEMENT, L.L.C.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	GREAT LAKES WINDOW, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	KROY BUILDING PRODUCTS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	MASTIC HOME EXTERIORS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name: 	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	MW MANUFACTURERS INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	MWM HOLDING, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	NAPCO, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	NEW ALENCO EXTRUSION, LTD.
	 	 	 
	 	By:	Alenco Extrusion Management, L.L.C., its general partner
	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name: 	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	NEW ALENCO WINDOW, LTD.
	 	 	 	 
	 	By:	Alenco Building Products Management, L.L.C., its general partner
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	NEW GLAZING INDUSTRIES, LTD.
	 	 	 	 
	 	By:	Glazing Industries Management, L.L.C., its general partner
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	PLY GEM PACIFIC WINDOWS CORPORATION
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name: 	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	PLY GEM SPECIALTY PRODUCTS, LLC
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	SIMEX, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	SIMONTON BUILDING PRODUCTS LLC
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	SIMONTON INDUSTRIES, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name: 	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	SIMONTON WINDOWS & DOORS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	SIMONTON WINDOWS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer
	 	 	 	 
	 	VARIFORM, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President, Secretary and Treasurer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	ATRIUM CORPORATION
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Chief Financial Officer
	 	 	 	 
	 	ATRIUM INTERMEDIATE HOLDINGS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Chief Financial Officer
	 	 	 	 
	 	ATRIUM PARENT, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Chief Financial Officer
	 	 	 	 
	 	AMERICAN SCREEN MANUFACTURERS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Chief Financial Officer
	 	 	 	 
	 	ATRIUM EXTRUSION SYSTEMS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Chief Financial Officer


 


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	 	EXISTING GUARANTORS (cont’d):
	 	 
	 	ATRIUM WINDOWS AND DOORS, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name: 	Shawn K. Poe
	 	 	Title:	Chief Financial Officer
	 	 	 	 
	 	CHAMPION WINDOW, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Chief Financial Officer
	 	 	 	 
	 	THERMAL INDUSTRIES, INC.
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Chief Financial Officer
	 	 	 	 
	 	SILVER LINE BUILDING PRODUCTS LLC
	 	 	 	 
	 	By:	/s/ Shawn K. Poe
	 	 	Name:	Shawn K. Poe
	 	 	Title:	Vice President and Secretary


 


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	 	WILMINGTON TRUST, NATIONAL ASSOCIATION,
	 	 
	 	as Trustee
	 	 	 
	 	By:	/s/ Joseph P. O'Donnell
	 	 	Name:   Joseph P. O'Donnell
	 	 	Title:   Vice President


 


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SCHEDULE 1


 


	 		New Subsidiary
    Guarantors		Jurisdiction
                                         of
 Organization

	1.	 	NCI Group, Inc.	 	Nevada
	2.	 	Robertson-Ceco II Corporation	 	Delaware
	3.	 	Steelbuilding.com, LLC	 	Delaware
	4.	 	Centria	 	Pennsylvania
	5.	 	Centria,
                                         Inc.



	 	Delaware
	6.	 	Centria
                                         Services
                                         Group, LLC



	 	Pennsylvania