TM

TM Underlayment and Tile Backerboard

Installation Guide Interior Floors, Walls and Countertops USG Fiberock® Brand Underlayment and Tile Backerboard

USG Fiberock® Brand underlayment and tile backerboard are all purpose substrates engineered to meet floor underlayment and wall tile-backing needs throughout a home. Under resilient flooring, USG Fiberock underlayment provides a hard surface that’s smooth and flat with no bumps or ridges to show through or affect finished floor covering. Behind and under tile or natural stone, USG Fiberock tile backerboard provides the resistance to water and mold that is required in bathrooms, kitchens and entryways. With USG Fiberock panels, you can rely on a single family of products to back all types of tile and resilient flooring in the home.

Integral Water Resistance Proven Performance This remarkable family of USG Fiberock panels are products is completely warranted for 20 years. different from other They have been tested by substrates. Manufactured the Tile Council of North with a unique, proprietary America (TCNA), using the technology, USG Fiberock Robinson Floor Method, and panels feature a durable, are approved for residential water-resistant composition and light commercial use (as that eliminates the defined by TCNA). swelling and warping often experienced with fiber Environmentally Friendly cement, , oriented USG Fiberock panels are made strand board (OSB), lauan from 95 percent recycled and other -based material. In recognition of the underlayments. environmentally sound alternative these panels Easy to Install provide, United States Gypsum USG Fiberock panels score Company earned the Green easily and snap with minimal Cross certificate from Scientific effort. In fact, the International Certification Systems, a leading CertifiedFloorcovering testing company that evaluates Installer Association awarded environmental claims. USG Fiberock underlayment the “Installer Friendly Seal.”

2 Introduction

Installing USG Fiberock panels tape and setting-type joint is quick and easy. Just follow compound. the simple installation steps in – Fasteners this booklet to create a perfect Wall Application: For steel base for tile or floor coverings. stud applications (20 ga. or equivalent), use 1-1/4" NOTE: Do not use USG or 1-5/8" USG Durock™ Fiberock panels over concrete screws for steel subfloors or over cushion- (or equivalent). For wood backed vinyl. stud applications, use 1/4", 1-5/8" or 2-1/4" USG Durock screws for wood framing Common tools like those (or equivalent) or 1-1/2" shown below are typically hot-dipped galvanized ring all that are needed to install shank roofing nails. USG Fiberock panels, though Floor Application: Use additional, specialized tools 1-1/4" USG Durock™ tile may be required with some backer screws for wood finish materials, such as tile framing (or equivalent) and natural stone. or 1-1/2" hot-dipped galvanized ring shank roofing nails. For resilient flooring, use minimum 1/4" crown point staples, hot-dipped galvanized ring shank nails or corrosion- resistant screws. Fastener length should be approximately equal to combined thickness of underlayment and subfloor. Materials Fasteners should not USG Fiberock Panels penetrate through subfloor. Size (thick x width x length) Units (pcs.) 1/4" x 4' x 4' 60 – Floor and Wall Framing 1/4" x 3' x 5' 60 Floor Tile Applications: 3/8" x 4' x 4' 60 Maximum joist spacing 3/8" x 4' x 8' 40 24" o.c. The subfloor system 3/8" x 3' x 5' 60 should be designed with a 1/2" x 3' x 5' 50 1/2" x 4' x 8' 30 minimum deflection limit 5/8" x 3' x 5' 40 of L/360 for the span. Some 5/8" x 4' x 8' 24 finish materials may require a more rigid subassembly – Sizes and Packaging (such as large format tile – Joint Reinforcement and natural stone products Behind ceramic tile, use L/720). In these cases, ™ USG Durock Brand tile follow the manufacturer’s backer tape and latex- minimum requirements. based Type I mastic or The subfloor should be latex-modified thin-set APA Span-Rated Plywood mortar. For sections that or OSB with an Exposure 1 will be painted, use paper classification or better with 3 Handling

tongue and or back – Protect panels from the blocked at the unsupported elements with adequate edges. covering during delivery and storage. Wall Applications: – Store panels flat on an even, Maximum stud spacing: dry surface. Allow panels to 16" o.c. for tile installation. acclimate to temperature 24" o.c. for non-tile and humidity at job site installations. Framing shall prior to installation. be designed (based on stud – Handle panels in an properties alone) not to upright position to prevent exceed L/360 deflection for breakage. tile, L/240 for surfaces that will be painted. Maximum Incorrect fastener spacing: 8" o.c. for wood and steel framing; 6" o.c. for ceiling applications.

– Patching Compound Use a high-quality patching compound such as USG Durock™ Fast Finish Floor Patch or equivalent Correct approved by the resilient- flooring manufacturer.

– Adhesive/Mortar Meeting ANSI A136.1: Type I ceramic tile adhesive. Meeting ANSI A118.1: dry-set mortar. Meeting ANSI A118.4: latex portland cement mortar. Incorrect

– Grout meeting ANSI A118.7.

– Ceramic tile meeting ANSI A137.1.

– Waterproof Membrane If waterproofing is desired, use USG Durock™ tile membrane installed with USG Durock™ tile membrane adhesive. See USG literature piece CB492 for USG Durock™ tile membrane product information.

4 Preparation

Crawl-Space Requirements Ensure that subfloor and Crawl-space requirements structure are within tolerances may vary based on specified by floor covering geographic location. Consult manufacturer. Inspect subfloor local building codes for more for even, flat surface before specific information regarding installing underlayment. vapor barriers and their uses. Uneven end edge joints and variations in subfloor panel Subfloor Requirements thickness may telegraph The subfloor system should be through underlayment in vinyl designed for a deflection limit applications. Sand uneven of L/360 for the span. The joints, if necessary. subfloor should be APA Span- Ensure that subfloor is flat Rated Plywood or OSB with between framing elements. an Exposure 1 classification If subfloor panels appear to or better with tongue and buckle, correct by adding groove or back-blocked at the blocking or cleats under floor. unsupported edges. Fasten cleats to subfloor to flatten panels. Repair voids, Resilient Flooring large gaps and penetrations Joist Minimum through subfloor using a Spacing Subfloor manufacturer-approved floor Thickness leveler prior to installing USG 16", 19.2" 23/32" Fiberock underlayment. and 24" o.c.

Over Existing Vinyl Floor Ceramic Tile CAUTION: Do not install USG Joist Minimum Spacing Subfloor Fiberock underlayment over Thickness heavily cushioned, thick foam- 16" o.c. 19/32" backed floor coverings. 19.2" o.c. 23/32" 24" o.c. 23/32" – Ensure that existing floor is level and meets appropriate Wood Subfloor design requirements. – Repair any missing or flush with or slightly broken vinyl tiles, curling below surface sand uneven seams, severe gouges, or joints protrusions by filling with fill and floor leveler. sand gaps If floor will be finished with ceramic tile, make sure that the existing vinyl covering is fully adhered and bonded to Clean subfloor and leave free the floor. of dust, dirt and debris. Ensure that subfloor is completely dry (no more than 12% moisture in subfloor prior to install). Verify that fasteners are flush with, or slightly below, subfloor surface.

5 and Laying Out Panels

Cutting Panels For more cutting techniques, Maintain temperature and consult your USG sales humidity in space approximate representative. to that of normal occupancy prior to, during and after Panel Layout installation. Install Lay cut edges against the underlayment, with fastener wall— only factory edges marks up. Panels may be cut should be joined. Begin laying by scoring and snapping with panels at one corner. Maintain a utility and straight 1/4" space between panels and edge, or by sawing, working perimeter walls. Stagger joints from the face side. With score- a minimum of 16" so that four and-snap method, score panel panel corners never meet, and twice and snap away from cut offset end and edge joints of face, then snap panel in panels a minimum of 12"–16" reverse direction to break the from subfloor panel joints. Butt back. Where necessary, use a panel edges and ends lightly or surform to smooth the together. =A maximum 1/32" cut edges. gap is allowed. Preparation for resilient flooring: Consider critical lighting when determining panel layout. Run continuous panel joints in the direction of the dominant source of natural light, when possible.

1/4" gap factory edges Cutouts

For difficult cuts, combine cut edge underlayment the score-and-snap method 16" 16" with use of a handsaw or low- RPM power . Cut holes for plumbing with a hole saw, subfloor or variable-speed . A power saw should be Prior to installation of final used only if equipped with a floor covering, avoid heavy dust-collection device. Always traffic and moving heavy items wear an OSHA-approved across panels. If necessary, dust mask when cutting USG items such as refrigerators or Fiberock panels with a power other appliances with wheels saw. (or on wheeled dollies) may be rolled over underlayment surface; using strips of hard wood or scrap underlayment to bear the wheel traffic is recommended. Allow a minimum of 24 hours after floor covering installation before placing heavy appliances or furniture on floor.

6 Floor Application

Ceramic Tile Finishing Joints Underlayment or Tile Backerboard Panel Application Apply Type 1 organic adhesive with 5/32" v-notched trowel, latex-fortified mortar with 1/4" -notched trowel. Comb out adhesive or mortar in straight, parallel rows (as shown below) and immediately cover with panel. Fill joints with latex-fortified Adhere panels to subfloor, one mortar or Type 1 organic panel at a time. adhesive and immediately embed USG Durock™ tilebacker tape or equivalent alkali- resistant, fiberglass mesh joint tape.

Ceramic Tile Installation

Fastening Fasten to subfloor with 1-1/4" USG Durock™ tile backer screws for wood framing (or equivalent) or 1-1/2" hot- dipped galvanized ring shank Sweep all debris from roofing nails spaced 8" o.c. in underlayment, and vacuum both directions with perimeter carefully to eliminate dust and fasteners at least 3/8" and dirt. less than 5/8" from ends and To set tile, apply latex- edges. Drive nails and screws fortified mortar or Type 1 so that bottoms of heads are organic adhesive with a flush with panel surface to notched trowel. Key in mortar ensure firm panel contact with or adhesive with flat side of subfloor. Do not overdrive trowel to prime USG Fiberock fasteners. surface, then comb out adhesive or mortar in straight parallel rows. When combing out adhesive or mortar, hold trowel at an angle to maintain uniform thickness.

7 Floor Application

Working a small area at 1/4 inch a time, set tile with a slight twisting motion and press into place. Avoid adhesive buildup on tile edge and in grout space. Keep tiles aligned so joints are straight and uniform. Use tile spacers if desired.

Note: Refer to ANSI A108.4 Consult your USG sales or A108.5 for complete tile representative for additional installation instructions. fastening techniques. Refer to setting material manufacturer for specific When using pneumatic tools, information related to trowel apply sufficient pressure on type and size, proper tile type gun to prevent the from and size, mixing instructions, bouncing. Set pneumatic tool and set and cure times. pressure to drive fasteners flush or slightly below underlayment Resilient Flooring surface. To prevent fastener Underlayment heads from telegraphing Selecting Fasteners through resilient floor covering, Fasten USG Fiberock do not more than underlayment to subfloor with 1/16" below surface. 1/4" crown chisel point staples. Fasten one panel at a time. Do not use screws or nails. Begin at one end and fan out Fastener length should across the floor. be approximately equal to combined thickness of Installing USG Fiberock underlayment and subfloor. Panels over Existing Vinyl Do not allow fasteners to Floor Coverings penetrate through subfloor. Do not install underlayment over heavily cushioned, thick Fastening Panels foam-backed vinyl. Ensure Lay panels flat and press tightly that existing floor is level, is onto subfloor while fastening. fully adhered and well bonded, Begin fastening where three and meets appropriate design panels intersect. Affix staples requirements. Repair missing along joints in a zipper pattern or broken tiles, curling seams, at 1" o.c., 1/4" from panel edge. severe gouges, protrusions of Install staples at 4" o.c. in the surface and any other damage field of panels. with a high-quality floor leveler. Follow floor-covering manufacturer's recommendations for installations over existing floors.

8 Correcting Joint recommendation for Imperfections nonporous substrates. Use USG Durock™ patching Follow floor-covering and/ compound or equivalent or adhesive manufacturer's sparingly to fill wide joints, guidelines for setting times repair any surface voids before allowing traffic on the and correct joint lippage finished floor. Follow floor- (panel edge sitting above covering manufacturer's or below the floor ). recommendations for Carefully fill joints wider preventive maintenance, than 1/32" and any surface cautions and procedures. imperfections with only enough material to infill void Perimeter-Bonded, Felt- – do not feather. Correct joint Backed Resilient Floor lippage by applying patching Covering compound to low side only Joint patching is not required and feathering to level. Allow with this type of floor covering compound to dry completely in new construction unless (90 min. minimum), then joint spaces or lippage exceed lightly sand or scrape, taking 1/32". Carefully fill joints wider care not to scuff panel surface; than 1/32" with only enough use a flat to scrape away material to infill void­—do any excess material. not feather. Correct joint lippage by applying patching compound to low side only and feathering to level. Allow compound to dry completely (90 min. minimum), then lightly sand or scrape, taking care not to scuff panel surface. Remove dust, dirt and debris from underlayment surface Remove all debris from panel before application of floor surfaces; vacuum carefully to covering. eliminate excess dust and dirt. Wood Flooring Underlayment Mechanically Fastened Wood Flooring Fasteners must be long enough to penetrate through USG Fiberock underlayment and into subfloor. To determine proper fastener length, add thickness of Applying Floor Covering underlayment to length of Refer to floor-covering fastener recommended by the manufacturer's flooring manufacturer. Follow recommendations for proper recommendations on pages procedures. For proper 6 and 8 for underlayment trowel selection, refer to installation. adhesive manufacturer's 9 Wall and Ceiling Application

Glued-Down Wood Flooring Shim Installation of engineered or Place a 1/4" spacer strip or solid glued-down shim around lip of bathtub or flooring must strictly follow shower pan to hold bottom manufacturer's instructions. edge of panel off the . Follow recommendations above for underlayment Joint Finishing installation. In areas that will be tiled, finish joints with USG Durock™ tile Ceramic Tile backer tape and latex-fortified Tile Backerboard mortar or Type I mastic. In Framing Requirements areas that will be painted: For ® Steel or wood wall framing taping, use USG Sheetrock shall be structurally sound Brand joint tape with USG ® ® and in compliance with local Sheetrock Durabond setting- building code requirements. type joint compound. For ® Damaged and excessively finishing, use USG Sheetrock bowed studs shall be replaced all purpose joint compound. ® before installation of tile Do not use Plus 3 lightweight ™ backerboard panels. all purpose or Midweight joint Space wood or steel framing compounds on USG Fiberock 16" o.c., maximum. Framing panels. shall be designed to meet L/360 deflection for tile. Planning Your Tile Installation Where tile will not cover entire Fastening wall surface, such as above Space fasteners 8" o.c. for the tub and shower surrounds, walls, 6" o.c. for ceilings. Fit determine where you want ends and edges of panels the tile to end and draw a level closely, but not forced line at this height. Be sure to together. allow for height of tile cap, if – Wood framing: 1-1/2" applicable. hot-dipped galvanized cap ring shank roofing nails height of tile or 1-1/4" USG Durock™ screws for wood framing or equivalent. cut – Steel framing: 1-1/4" cut USG Durock™ screws for steel framing or equivalent. cut – Joining: Fill joints with floor level latex-fortified mortar or Type 1 organic adhesive and immediately embed USG Durock™ tape or equivalent alkali-resistant, fiberglass mesh joint tape.

10 Countertop Application

Determine whether floor is Cover plywood base with USG level by measuring distance Durock™ tile membrane, 15 lb. to desired tile height on both felt or 4 mil polyethylene and sides of area to be tiled. If attach with 1/4" galvanized there is a difference (i.e., the . floor is lower on one side), lay one vertical row of tile from desired tile height to low point of floor. Affix tiles with tile- setting materials. Use this first row as a guide to keep tiles and grout lines level and even throughout installation. If new flooring will be installed, allow for thickness of new flooring where the wall Position meets the floor. Fit ends and edges of panels closely, but not forced Installing Ceramic Tile together. Stagger panel joints from plywood base joints.

Fasten Space fasteners 8" o.c. around the perimeter and in the field of the board.

Joining Fill joints with latex-fortified mortar or Type 1 organic Always follow current ANSI adhesive and immediately specifications and TCNA embed alkali-resistant, guidelines for installing tile. fiberglass mesh joint tape.

Apply tile-setting material to tile backerboard with notched trowel; key in mortar or adhesive with smooth side of trowel to prime USG Fiberock surface first, then comb out mortar or adhesive in straight parallel rows, hold trowel at min. 45º angle to maintain uniform thickness. Finish Working a small area at a Install tile. time, set tile with a slight NOTE: Because cement board twisting motion and press into fasteners may protrude place. Keep tiles aligned so through the plywood base joints are straight and uniform. when 1/4" cement board is Use tile spacers if desired. If used, 1/2" or 5/8" cement excess adhesive squeezes from board is preferred in this under tile, remove before it application. dries. 11 Trademarks Product Information The trademarks USG, DURABOND, See usg.com for the most DUROCK, FIBEROCK, MIDWEIGHT, up-to-date product information. PLUS 3, SHEETROCK, the USG logo, the design elements and colors, and Safety First! related marks are trademarks of USG Follow good safety and industrial hygiene Corporation or its affiliates. practices during handling and installation of all products and systems. Take necessary Note precautions and wear the appropriate Products described here may not be personal protective equipment as needed. available in all geographic markets. Read material safety data sheets and Consult your United States Gypsum related literature on products before Company sales office or representative specification and/or installation. for information. Manufactured by Notice United States Gypsum Company We shall not be liable for incidental 550 West Adams Street and consequential damages, directly Chicago, IL 60661 or indirectly sustained, nor for any loss caused by application of these goods For warranty or product not in accordance with current printed information and literature instructions or for other than the 800 USG.4YOU (874-4968) intended use. Our liability is expressly usg.com limited to replacement of defective goods. Any claim shall be deemed F119/rev. 2-19 waived unless made in writing to us © 2019 USG Corporation and/or its within thirty (30) days from date it affiliates. All rights reserved. was or reasonably should have been Printed in U.S.A. discovered.