PermaBase®

BRAND

Cement BoardConstruction Guide

09 28 00/NGCBuyLine 1854

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PermaBase®

Cement BoardDescriptionPermaBase® Cement Board is arigid substrate made of Portlandcement, aggregate and glass meshthat provides an exceptionally hard,durable surface that is able to with-stand prolonged exposure to moisture.

PermaBase offers a competitiveadvantage over similar products on the market with its patentedEdgeTech® technology. The tapered,double-wrapped edge designallows for closer nail or screwapplication to the edge.

Features/Benefits� Double-wrapped edge with

EdgeTech technology allows forcloser fastener application ofnails or screws at the edgewithout crumbling or spinout.

� IRC and IBC 2006 Compliant – Meets ASTM C 1325.

� PermaBase resists the growthof mold and mildew achievinga panel score of 10, the highestscore possible, per ASTM D 3273.*

� Homogeneous core has fewervoids and provides a very easyand clean score and snap.

� Can be cut utilizing a standard utility knife and straightedge.With PermaBase’s unique corecomposition, little or no addi-tional labor is needed to cleanthe edge after a cut.

� PermaBase is impact resistant,extremely durable and dimen-sionally stable. It has excellentoverall flexural, compressive andtensile strength characteristics.

� PermaBase is highly moistureresistant, and will not rot, disintegrate or swell whenexposed to water.

� 1/2" PermaBase may be used in 1 hour and 2 hour ratedassemblies and is UL Classified.

� PermaBase has a smoother finish than other brands andhas no open edges, whichreduces hand chafing.

� 1/4" PermaBase is ideal forremodeling applications becauseit can be applied directly overexisting countertop surfaces.

� As a floor underlayment 1/4"PermaBase eliminates the needto modify adjacent thresholdswhen abutting to carpeting,wood flooring and other commonflooring materials.

� Lowest water absorption of anycement board per ASTM C 473.

� Can be used in residential andcommercial saunas and steamrooms.

� Available in various widths,lengths and thicknesses.

� Can be used in 24" o.c. floortruss construction, with specificrequirements.

� Suitable for both interior andexterior applications.

Warranty� 30-year limited warranty for

interior applications.

� 10-year limited warranty forexterior applications.

� Not recommended for use withvinyl flooring.

� For exterior and interior finishesapplied direct to PermaBase,reinforcing mesh must beembedded in basecoat. Consult finish manufacturer foradditional requirements.

� PermaBase Cement Boardshould not be exposed to tem-peratures over 220˚F (105˚C).

CompositionCementitious Backer Unit(CBU): PermaBase Cement Boardis a nailable, screwable backerboardor underlayment panel which iscomposed of Portland cement,aggregates and reinforcementsthat has a significant ability toremain unaffected by prolongedexposure to moisture. PermaBasecomplies with ASTM C 1325 andANSI A118.9.

Limitations� Joints should be treated with

alkali resistant fiberglass meshtape set in a latex-Portlandcement mortar.

� Conventional paper drywall tape,joint compound and drywall nailsor screws should not be used.

� Maximum wall framing spacingshould not exceed 16" o.c. and must be designed to limitdeflection to L/360 under all live and dead loads.

� Steel framing must be 20 ga.(galvanized) or heavier – 16" o.c.

� 1/4" PermaBase should not beused on walls or ceilings.

� PermaBase Cement Board is nota water barrier. Consult localbuilding code for moisture barrierrequirements.

A. Double-wrapped edge with EdgeTech®

technology

B. Fiberglass mesh

C. Cementitious core

AB

C

* When tested by an independent laboratory per ASTM D 3273 ("Standard Test Method for Resistance to Growth of Mold on the Surface of Interior Coatings in an Environmental Chamber"), PermaBase achieved a panel score of 10, the highest score possible, indicating no mold growth under the laboratory test conditions. The use of PermaBase in actual installations may not produce the same results as were achieved in controlled laboratory conditions. No material can be considered "mold proof," nor is it certain that any material will resist mold indefinitely.

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ApplicationsAn ideal underlayment for interior applications such as:

� Shower and tub enclosures

� Garden/whirlpool tubs

� Countertops

� Backsplashes

� Steamrooms and saunas

� Swimming pool and whirlpooldecks and enclosures

� Floor underlayment– Entryways– Kitchens– Bathrooms– Foyers– Laundry rooms

InstallationGeneral: All framing should complywith local building code require-ments and be designed to providesupport with a maximum allowabledeflection of L/360 under all intend-ed loads. Framing members shouldbe spaced a maximum of 16" o.c.

Note: Cut or score PermaBase onprinted side of panel. Install tileand tile setting materials in accor-dance with current ANSI specifica-tions and Tile Council of America(TCA) guidelines.

Control Joints: For interior installa-tions, allow a maximum of 30 linealfeet between control joints. A controljoint must be installed but not limitedto the following locations: whereexpansion joints occur in the framingor building (discontinue all cross furringmembers located behind joint); whenboards abut dissimilar materials;where framing material changes; at changes of building shape or struc-tural system; at each story separation.Place control joints at corners ofwindow and door openings, or followspecifications of architect. Controljoint cavity shall not be filled withcoating or other materials.

WALLS & CEILINGS

Wall Framing: Edges of PermaBaseparallel to framing should be contin-uously supported. Provide additionalblocking when necessary to permitproper PermaBase attachment.

Do not install PermaBase directlyover protrusions from stud planesuch as heavy brackets and fastenerheads. Studs above a shower floorshould either be notched or furred to accommodate the thickness of the waterproof membrane or pan.The surround opening for a tub or

Interior Applications

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precast shower receptor should notbe more than 1/4" longer than unitto be installed.

Ceiling Framing: The deflectionof the complete ceiling assemblydue to dead load (including insula-tion, PermaBase, bonding materialand facing material) should notexceed L/360. The dead loadapplied to the ceiling frame shouldnot exceed 10 psf. Ceiling joist orfurring channel should not exceed16" o.c. (Edges of PermaBase parallel to framing should be

continuously supported.) Provideadditional blocking when necessaryto permit proper PermaBaseattachment.

PermaBase Cement Board: ApplyPermaBase with ends and edgesclosely butted but not forced together.Stagger ends joints in successivecourses. Drive fasteners into field ofcement board first, working towardends and edges. Space fastenersmaximum 8" o.c. for walls, 6" o.c.for ceilings with perimeter fasteners

TUB & SHOWER SURROUND

PermaBase Cement Board

Tile

Adhesive orLatex-Portland

Cement Mortar

XP® GypsumBoard

Fiberglass Mesh Tape(Alkali Resistant)

PermaBaseCement Board Screws, 8" o.c.

PermaBase Cement Board

2"x 4" Wood Studsor 20 ga. 3-5/8"Metal Studs 16" o.c.

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at least 3/8" and less than 5/8"from ends and edges. EnsurePermaBase is tight to framing.

Joint Reinforcement: Trowelbonding material to completely fillthe tapered recessed board jointsand gaps between each panel. Onnon-tapered joints apply a 6" wide,approx. 1/16" thick coat of bondingmaterial over entire joint. For alljoints, immediately embed 2" alkaliresistant fiberglass mesh tape fullyinto applied bonding material andallow to cure. Same bonding materi-al should be applied to corners, con-trol joints, trims and other acces-sories. Feather bonding materialover fasteners to fully conceal.

FLOORS & COUNTERS

Subfloor or Base: For flooringapplications with 16" o.c. floorjoists, 5/8" tongue and grooveexterior grade plywood or 3/4"tongue and groove exterior gradeOSB may be used. For 19.2" o.c.and 24" o.c. floor joists, 3/4"tongue and groove exterior gradeplywood or OSB must be used. Tilesize for floors with 24" o.c. floorjoists must be 12" x 12" or larger.The joist and subfloor assembly mustmeet L/360 as well as the appropriatecode tables for live and dead loads.

Underlayment: Using a 1/4"square-notched trowel, apply a setting bed of latex-Portlandcement mortar (or thin-set mortar)

to the subfloor or counter base.Immediately laminate PermaBase tosubfloor or base leaving a 1/8"space between boards at all jointsand corners. Leave a 1/4" gap along walls.

Stagger all joints so that they do not line up with underlyingsubstrate joints. Fasten PermaBaseevery 8" o.c. throughout boardfield and around all edges whilesetting bed mortar is still workable.Around perimeter of each board,locate fasteners 2" from cornersand not less than 3/8" from theedges. Fill all joints solid withbonding material. On non-taperedjoints such as butt ends, apply a

6" wide, 1/16" thick coat over theentire joint. For all joints, immedi-ately embed 2" fiberglass meshtape fully into applied bondingmaterial; ensure that tape is centered over joint. Apply bondingmaterial over fasteners to fullyconceal. Remove all excess bondingmaterial and allow to cure.

FLOOR UNDERLAYMENT COUNTERTOP

Fiberglass Mesh Tape(Alkali Resistant)

Cabinet

Plywood

Latex-PortlandCement Mortar

Latex-PortlandCement Mortar

PermaBase Cement Board

Tile

Tile

I-Joists

Plywood

PermaBase Cement Board

Latex-PortlandCement Mortar

Fiberglass Mesh Tape(Alkali Resistant)

Latex-PortlandCement Mortar

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ApplicationsAn ideal substrate for exteriorapplications such as:

� Tile applications

� Stucco applications

� Countertops

� Soffit panels

� Sheathing panels

� Decks

� Outdoor kitchens/grills

InstallationGeneral: All framing should comply with local building coderequirements and be designed toprovide support with a maximumallowable deflection of L/360under all intended live (includingwind) and dead loads.

Note: Cut or score PermaBase onrough side of panel. Install tile andtile setting materials in accordancewith current ANSI specificationsand Tile Council of America (TCA)guidelines.

Control Joints: For exterior instal-lations, allow a maximum of 16 lineal feet between control joints.(For exterior tile applications, controljoints should be spaced a maximumof every 12'.) A control joint must beinstalled but not limited to the following locations: where expansionjoints occur in the framing or building(discontinue all cross furring memberslocated behind joint); when boardsabut dissimilar materials; whereframing material changes; at changesof building shape or structural system;at each story separation. Place control joints at corners of windowand door openings, or follow specifi-cations of architect. Control jointcavity shall not be filled with coatingor other materials.

DECKS

Subfloor: Plywood should besecurely glued and fastened tofloor joists spaced a maximum of16" o.c. Subfloor should be slopedat a minimum pitch of 1/4" perfoot. The floor surface should betrue to plane within 1/8" in 10'.

Underlayment: Using a 1/4"square-notched trowel, apply a setting bed of latex-Portland cementmortar to the subfloor. Immediatelylaminate PermaBase to subfloor,leaving a 1/8" space betweenboards at all joints and corners.Leave a 1/4" gap along walls.Stagger all joints so they do not lineup with underlying substrate joints.Fasten PermaBase every 8" o.c.throughout board field and aroundall edges while setting bed mortar isstill workable. Around the perimeterof each board, locate fasteners 2"from the corners and not less than3/8" from the edges. Fill all jointssolid with bonding material. On non-tapered joints such as butt ends,apply a 6" wide, 1/16" thick coatover the entire joint. For all joints,immediately embed alkali resistantfiberglass mesh tape fully intoapplied bonding material; ensurethat tape is centered over joint. Applybonding material over fasteners tofully conceal. Remove all excessbonding material and allow to cure.

Waterproof Membrane: Trowelapply waterproof membrane to theentire surface of the PermaBase, following membrane manufacturer’sinstallation instructions in detail.

WALLS & CEILINGS

Wall Framing: Studs should bespaced a maximum of 16" o.c.Edges/ends of PermaBase parallelto framing should be continuouslysupported. Provide additionalblocking when necessary to permitproper PermaBase attachment. Donot install PermaBase directly overprotrusions from stud plane such asheavy brackets or fastener heads.

Ceiling Framing: The deflectionof the complete ceiling assemblydue to dead load (including insula-tion, PermaBase, bonding materialand facing material) should notexceed L/360. The dead loadapplied to the ceiling frame shouldnot exceed 10 psf. Ceiling joist orfurring channel should not exceed16" o.c. (Edges of PermaBase parallel to framing should be continuously supported.) Provideadditional blocking when necessaryto permit proper PermaBaseattachment.

Exterior Applications

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Weather Barrier: WhilePermaBase is unaffected by moisture, a water barrier must beinstalled to protect the cavity. Itshould be installed according tothe manufacturer’s specifications.

PermaBase Cement Board:Apply PermaBase with ends andedges closely butted but not forcedtogether. Stagger end joints in successive courses. Drive fastenersinto field of cement board first,working toward ends and edges.Space fasteners maximum 8" o.c.for walls, 6" o.c. for ceilings withperimeter fasteners at least 3/8"and less than 5/8" from ends and edges.

Joint Reinforcement: Trowelbonding material to completely fillthe tapered recessed board jointsand gaps between each panel. Onnon-tapered joints apply a 6"wide, approx. 1/16" thick coat ofbonding material over entire joint.For all joints, immediately embed4" alkali resistant fiberglass meshtape fully into applied bondingmaterial and allow to cure. Samebonding material should beapplied to corners, control joints,trims or other accessories. Featherbonding material over fasteners tofully conceal.

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DescriptionCement Board Stucco is a water-managed exterior wall systemdesigned to provide increased high-impact and weather resistance andimproved dimensional stabilitywhere exterior insulation value isnot required. For the purposes ofmeeting structural racking or firecode requirements, it is appliedover the following approvedsheathings: Exposure 1 or exteriorplywood (grade C-D or better);Exposure 1 OSB; glass mat gypsumsubstrate meeting ASTM C 1177; or water resistant core gypsum(ASTM C 1396).

It combines the strength and dura-bility of PermaBase Cement Boardwith the performance and beauty ofreinforced base coats and texturedfinishes. All finishes are available ina limitless color selection and offer performance enhancementoptions ranging from extra mildewresistance to added flexibility.

Behind the system, a weather-resistant barrier complying withASTM D-226 protects approvedsheathings and other structuralcomponents and serves as a component to evacuate incidentalwater. Cement Board Stucco allowsyou to enclose and finish a projectin as little as two days, speedingoccupancy.

UsesFor high-impact and weather-resis-tant exterior wall in residential andlow-rise commercial applications.

AdvantagesDurability/Strength: Moistureresistant, durable PermaBaseCement Board substrates appliedover a primary sheathing provideextraordinary impact and punctureresistance to the system.

Weather Resistance: 100%Acrylic base coats and finishes repelweather at the system’s surface.

Water-Managed Design: Thewater-managed design of the system provides drainage to theexterior of incidental water thatmight enter around or throughwindow or door openings andpenetrate behind the cladding inframe construction.

Water-Managed, High-Impact Resistant Wall System

Design Options: Cement BoardStucco provides the popular stuccolook, including the attachment ofspecial pre-molded shapes and awide variety of finish texture andcolor options in standard colorsand custom colors.

Contact exterior coatings manufacturer for color and installation instructions.

Limitations� Use is limited to residential and

low-rise commercial applications.

� Thin veneer construction will tendto reveal planar irregularities inthe frame construction.

� Minor cracking at joints mightbecome visible in the finishedexterior surface.

� For exterior finishes applieddirect to PermaBase, reinforcingmesh must be embedded inbasecoat. Consult exterior manufacturer for additionalinstallation requirements.

� For conventional PortlandCement plaster systems, self-furring metal lath must be used over PermaBase andadhered to studs.

CEMENT BOARD STUCCO WALL SYSTEM

Framing

Acceptable Sheathing

Moisture Protection Barrier (By Others)

PermaBase® BRANDCement Board

Base Coat

4" Mesh Tape

Exterior Finish

Flashing Or Starter Track

Base Coat

Corrosion ResistantFasteners

Reinforcing Mesh

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1-Hour Rating

1/2" PermaBase

Steel studs (with 3" mineral fiber insulation)

5/8" Fire-Shield Gypsum Wallboard

2-Hour Rating

1/2" PermaBase

Steel studs (with 3" mineral fiber insulation)

1/2" Fire-Shield C Gypsum Wallboard

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Technical DataFire-Rated Wall Assemblies

PermaBase Cement Board has beentested and/or approved for use in avariety of fire-rated wall systems.

1-Hour Rating – The 1-hour wallassembly consists of 3-5/8" steelstuds, 16" o.c., one layer of 1/2"PermaBase attached horizontally orvertically with 1-1/4" long cementboard screws 8" o.c. in the fieldand perimeter on one side and onelayer of 5/8" Fire-Shield® wallboardattached vertically on opposite sidewith joints staggered to those ofopposite side, with 1-1/4" longdrywall screws 8" o.c. in the fieldand perimeter with 3" thick mineralfiber insulation batts in the stud cavities. UL V452, ITS/WHIReport No. J99-4001.

2-Hour Fire Rating – The 2-hourwall assembly consists of 3-5/8"steel studs, 16" o.c. on one side,base layer of 1/2" Fire-Shield Cwallboard attached vertically with1" drywall screws 24" o.c. in thefield and perimeter and face layer of1/2" PermaBase attached verticallywith 1-5/8" cement board screws,8" o.c. in the field and perimeter.Two layers of 1/2" Fire-Shield Cwallboard applied vertically to theopposite side, base layer attachedwith 1" drywall screws 24" o.c. inthe field and perimeter and facelayer attached with 1-5/8" drywallscrews 12" o.c. in the field andperimeter, with 3" thick mineralfiber insulation batts in the studcavities. All joints staggeredbetween face and base layer. UL V452, ITS/WHI Report No. J98-32931.

PermaBase® BRAND Cement BoardTechnical Data

Shea

r Bon

d St

reng

th7

days

(psi)

PermaBase meets the following codes and standards:

2006 International Residential Code2006 International Building CodeASTM C 1325ANSI A118.9ICC Acceptance Criteria 59 (AC59)

Code Report References

ICBO ES Inc. ER-5731PermaBase Cement Board

National Evaluation Service Inc. Report No. NER-578PermaBase Cement Board

PHYSICAL PROPERTIES

Property Test Method 1/2" PermaBase

Water Absorption % ASTM C 473 <8by Weight/24 Hours

Flexural Strength (psi) ASTM C 947 750

Fastener Holding ASTM D 1037 90(Wet and Dry, lbs.) (0.400" head diameter)

Weight (psf) ASTM C 473 3

Freeze/Thaw (cycles) ASTM C 666 100per ANSI A118.9 Procedure B

Flame Spread/ ASTM E 84 0/0Smoke Developed

Compressive Strength (psi) ASTM D 2394 2250(Indentation)

Wind Load ASTM E 330 40(psf, studs 16" o.c.)

Thermal “R”/k Value Property of Material 0.2/2.7

Bending Radius (ft.) Property of Material 5

Standard Method for ASTM C 627 Lightevaluating ceramic Commercialfloor installation system

Falling Ball Impact ASTM D 1037 pass(12" drop)

Dry-Set Portland ANSI A118.1 204Cement Mortar

Latex-Portland ANSI A118.4 241Cement Mortar

Organic Adhesives ANSI A136.1 159Type 1

Linear Variation ASTM D 1037 0.05%(Due to change inmoisture content)

Fungus Resistance ASTM G 21 (No growth)

Mold Growth on Surface ASTM D 3273* 10

* When tested by an independent laboratory per ASTM D 3273 ("Standard Test Method for Resistance to Growth of Mold on the Surface of Interior Coatings in an Environmental Chamber"), PermaBase achieved a panel score of 10, the highest score possible, indicating no mold growth under the laboratory test conditions. The use of PermaBase in actual installations may not produce the same results as were achieved in controlled laboratory conditions. No material can be considered "mold proof," nor is it certain that any material will resist mold indefinitely.

Rev. 10/08

Corporate Headquarters

National Gypsum Company2001 Rexford RoadCharlotte, NC 28211

Phone: (704) 365-7300Web: nationalgypsum.com

nationalgypsum.com/espanol

Technical Information

Phone: (800) NATIONAL(800) 628-4662

Fax: (800) FAX-NGC1(800) 329-6421

SpecificationsSection 09 28 00 Cement Board

A. This section is written in CSI 3-part format and it assumes thatthe general conditions of the contract will be AIA A201. This section is proprietary and includesonly National Gypsum products.

PART 1 GENERAL

1.01 Summary

A. Section includes:

1. Cement backerboard for ceramictile, other interior and exteriorapplications for walls and ceilings.

2.Underlayment for ceramic tile installations for interior andexterior floors.

3.Substrate for ceramic tileinstallation for interior and exterior countertops.

1.02 Submittals

A. Product Data: Manufacturers’specifications and installationinstructions for each productspecified.

1.03 Delivery, Storage, and Handling

A. Packaging and Shipping: Havematerials shipped in manufac-turer’s original packages showing manufacturer’s nameand product brand name.

B. Storage and Protection: Storematerials inside and protectedfrom damage by the elements.Protect ends, edges, and facesof cement boards from damage.

PART 2 PRODUCTS

2.01 Manufacturer

A. National Gypsum Company

2.02 Materials

A. Cement Board

1. Backer Board: Cementitious,water-durable board; surfacedwith fiberglass reinforcing meshon front and back; long edgeswrapped; and complying withANSI A118.9 and ASTM C 1325(PermaBase BRAND Cement Board).

a. Thickness: 1/2" or 5/8"b. Width: 2' 8", 3', or 4'c. Length: 4', 5', 6', or 8'd. Edges: Taperede. Density: 72 lbs. per cu. ft.f. Water Absorption: Not greater

than 8% when tested for 24 hoursin accordance with ASTM C 473.

2. Bendable Backer Board:Cementitious, water-durableboard; surfaced with fiberglassreinforcing mesh on front andback; long edges wrapped; andcomplying with ANSI A118.9(PermaBase Flex BRAND CementBoard).

a. Thickness: 1/2"b. Width: 4'c. Length: 8'd. Edges: Taperede. Density: 72 lbs. per cu. ft.f. Water Absorption: Not greaterthan 8% when tested for 24 hoursin accordance with ASTM C 473.

3. Underlayment: Cementitious,water-durable board; surfacedwith fiberglass reinforcing meshon front and back; long edgeswrapped; and complying withANSI A118.9 and ASTM C 1325(PermaBase BRAND Cement Board).

a. Thickness: 1/4"b. Width: 3' or 4'c. Length: 5'd. Edges: Taperede. Density: 72 lbs. per cu. ft.f. Water Absorption: Not greaterthan 8% when tested for 24 hoursin accordance with ASTM C 473.

B. Fasteners:

1. Nails: 1-1/2" long, hot dippedgalvanized, for use with woodframing and complying withFederal Specification FF-N-105B,Type 2, Style 20.

2.Screws: PermaBase CementBoard Hi-Lo thread screws (No.8), wafer head, corrosion-resis-tant, 1-1/4" or 1-5/8" long, foruse with wood framing andcomplying with ASTM C 1002.

3. Screws: PermaBase CementBoard drill point screws (No. 8)wafer head, corrosion-resistant, 1-1/4" or 1-5/8" long, for use with20 to 14 ga. steel framing andcomplying with ASTM C 1002.

C. Joint Treatment:

1. Tape: Alkali-resistant fiberglassmesh tape for joint reinforcement,2" wide mesh tape for interiorapplications and 4" wide meshtape for exterior applications.

2. Bonding Materials: Latex-Portland cement mortar or Dry-Set(thin-set) mortar, for joint treat-ment and setting face material,complying with ANSI A118.1 orA118.4 standards. Type 1 organicadhesive meeting ANSI A136.1may be utilized for interior use only.

PART 3 EXECUTION

3.01 Installation

A. General: In accordance with man-ufacturer’s recommendations.National Gypsum Company“PermaBase Cement BoardConstruction Guide” and the following standard:

1. Installation of cementitiousbacker units: ANSI A108.11.

3.02 Protection

A. Protect cement board installationsfrom damage and deteriorationuntil the date of substantial completion.

LIMITED WARRANTY AND REMEDIESProducts manufactured and sold byNational Gypsum Company are warrantedby National Gypsum Company to its cus-tomers to be free from defects in materialsand workmanship at the time of shipment.THIS EXPRESS WARRANTY IS THE ONLYWARRANTY APPLICABLE TO SUCHPRODUCTS, AND IS IN LIEU OF ANDEXCLUDES ALL OTHER EXPRESS ORALOR WRITTEN WARRANTIES AND ALLIMPLIED WARRANTIES, INCLUDING BUTNOT LIMITED TO THE IMPLIED WAR-RANTIES OF MERCHANTABILITY ANDFITNESS FOR A PARTICULAR PURPOSE.

National Gypsum Company will not beliable for any incidental, indirect or con-sequential losses, damages or expenses.The customer’s exclusive remedy for anytype of claim or action for defective products will be limited to the replacementof the products (in the form originallyshipped) or, at National Gypsum’s option,to a payment or credit not greater thanthe original purchase price of the products.

National Gypsum Company will not beliable for products claimed to be defec-tive where the defect resulted fromcauses not within National Gypsum’scontrol, or which arose or occurred aftershipment, including but not limited toaccidents, misuse, mishandling, improperinstallation, contamination or adulterationby other materials or goods, or abnormalconditions of temperature, moisture, dirtor corrosive matter.

Any claim that products sold by NationalGypsum Company were defective or other-wise did not conform to the contract ofsale is waived unless the customer submitsit in writing to National Gypsum withinthirty (30) days from the date the customerdiscovered or should have discovered thedefect or nonconformance. No legal actionor proceeding complaining of goods soldby National Gypsum may be brought bythe customer more than one year afterthe date the customer discovered orshould have discovered the defect orproblem of which it complains.