Frequently Asked Questions

  • Product/Performance
    • What sets the USG Durock™ Shower System apart from other systems on the market?

      The USG Durock™ Shower System is a fully-bonded waterproofing system for tiled shower installations, designed to control moisture independently of the tile covering while creating a solid base for a long-lasting shower. The components are lightweight and can be installed faster and more easily than traditional mud bed shower construction. And, because the USG Durock™ Shower System comes from a manufacturer with a reputation for delivering high-quality materials, you can trust that it will deliver performance superior to other systems on the market.

    • What is the difference between the Pro and Designer Series grates?

      Pro Series grates utilize an extremely durable, high impact-resistant, engineering-grade polycarbonate base structure wrapped in stainless steel. The key difference is that Pro Series grates are equipped with a Physical Vapor Deposition (PVD) finish that is bonded to the stainless steel at the molecular level and provides trusted durability and extraordinary scratch and wear resistance.

      Designer Series grates offer a range of stylish choices to fit your unique shower design. Each grate is cut from a solid block of 3/16 in.-thick stainless steel, optimized for high strength and corrosion resistance. The reflective facets around each opening are meticulously crafted for the most discriminating high-end shower installations.

    • Are the USG Durock™ Shower System grates sold separately?

      Yes. Both the Designer and Pro and Designer Series Grates are sold separately from the kit. With seven square designs, two sizes, and more than 10 finishes, the USG Durock™ Shower System offers more than 50 grate options to match your decor. Linear drain grates are also available, visit www.usgid.com.

    • Can I upgrade my Pro Series grate to a Designer Series grate after it has been installed?

      Yes. You can upgrade to a Designer Series grate at any time. The USG Durock™ Shower System drain grate tray accepts both the Designer and Pro Series grates.

    • What makes the USG Durock™ Shower System drain unique?

      The most distinctive trait of the USG Durock™ Shower System Drain Assembly is its innovative, square design, which accepts both 4 in. and 5 in. Pro or Designer grates in a single drain body. This geometry allows more lateral adjustment than traditional round-body drains.

      The USG Durock™ Shower System Drain Assembly also features an innovative bushing design – one PVC and one ABS bushing included with drain assembly – that allows for solvent-weld and no-hub connections to 2 in. or 3 in. ABS or PVC waste lines. This, combined with the square geometry, makes it the only universal drain on the market.

      Furthermore, unlike competitive offerings, the drain’s integrated bonding flange features a nonwoven fleece on both the top and the bottom of the flange. The fleece on top provides ample surface adhesion for the waterproofing membrane, while the fleece on the underside provides the necessary bonding surface for the mortar that supports the drain assembly. The fleece is co-molded with the ABS drain body to ensure the highest possible permanent bond.

    • How does the USG Durock™ Shower System waterproofing membrane deliver twice the performance at half the thickness?

      The waterproofing membrane features an oriented high-density polyethylene (HDPE), cross-laminated core that provides strength and tear resistance at much thinner millimeter thicknesses (0.12 mil). This makes it the most pliable, user-friendly membrane in the industry with the least amount of buildup at seams.

      Since the waterproofing membrane has the lowest permeability rating of any bonded waterproofing membrane on the market when tested to ASTM E96 Procedure E (<0.075), it is ideal not only for showers and other wet areas, but for continuous-use residential and commercial steam showers. 

    • What is the material composition of the USG Durock™ Shower System shower trays, shower curb and shower benches?

      The USG Durock™ shower trays, curb and benches are made of 3-pound density expanded polystyrene (EPS), offering greater support for the tile covering in shower applications. And because the shower trays are only 1 in. thick at the perimeter, barrier-free installations are much easier to construct without unwanted or unnecessary buildup of the surrounding subfloor. All it takes is just a few simple adaptations to wood-framed construction.

    • What’s the dimension from the wall to the center of the drain for your standard shower tray sizes?

      We offer the following standard shower tray sizes:

      • On the 32 in. x 60 in. offset tray, the center of the drain is 10 in. from the wall lengthwise and 16 in. from the adjacent wall widthwise.
      • On the 32 in. x 60 in. center tray, the center of the drain is 30 in. from the wall lengthwise and 16 in. from the adjacent wall widthwise.
      • On the 48 in. x 48 in. center tray, the center of the drain is 24 in. from the wall lengthwise and 24 in. from the wall widthwise.
      • On the 72 in. x 72 in. center tray, the center of the drain is 36 in. from the wall lengthwise and 36 in. from the wall widthwise.


      The USG Durock™ Shower System Shower Trays can be cut to size using a utility knife. Ideally, the tray should be cut equally on each side to maintain a level perimeter for the first course of tile. In the event this is not possible, minor differences in the elevation of the perimeter can be built up with thin-set mortar. If the area of the shower floor is larger than the USG Durock™ Shower System shower tray, the area beyond the perimeter of the tray can be extended using dry pack mortar.

    • What if the USG Durock™ Shower System Shower Tray doesn’t fit the footprint of my shower floor?

      The USG Durock™ Shower System Shower Trays can be cut to size using a utility knife. Ideally, the tray should be cut equally on each side to maintain a level perimeter for the first course of tile. In the event this is not possible, minor differences in the elevation of the perimeter can be built up with thin-set mortar. If the area of the shower floor is larger than the USG Durock™ Shower System shower tray, the area beyond the perimeter of the tray can be extended using dry pack mortar. Custom shower tray options are also available. 

  • Installation
    • Can I build a barrier free (curbless) shower with the USG Durock™ Brand Shower System?

      Yes. The USG Durock™ Shower System Pre-sloped Shower Trays are 1 in. thick at the perimeter, making it possible to create a barrier free shower in wood-framed construction without cutting the floor joists, while at the same time avoiding unwanted or unnecessary buildup of the surrounding subfloor.

      USG Durock™ Shower System Ramps are also available. They are designed to integrate with the USG Durock™ Shower System Pre-sloped Shower Trays, and allow for easy construction of barrier-free showers. They are made of the same durable 3-lb. density EPS foam as the USG Durock™ Shower System Trays and are offered in two sizes: 12 in. x 48 in. and 12 in. x 60 in. They slope from 1 in. to 1/4 in. on the 12 in. side.

      For a representation of a barrier-free installation over a wood subfloor, navigate to our installation videos under Pro Resources.

    • Can I cut the curb down in height, width and length?

      Yes, the USG Durock™ Shower System Curbs can be cut down to fit your requirements. Note: If the curb is cut down in the width dimension to the extent that the hollow sections of the curb become exposed, then the hollow sections should be filled with mortar prior to installing the waterproofing membrane and tile.

    • How do you fasten shower door hardware to the curb?

      In cases where the hardware is designed to be fastened to a shower curb, the hardware is installed after the curb has been tiled and grouted. Subsequently, the tile is marked and drilled and the hardware is installed with stainless steel screws and plastic anchors. Sealant should be applied in the holes prior to placing the anchors.

    • Can I cut down the USG Durock™ Shower System Benches?

      Yes. Our benches are constructed of solid core 3-lb. density EPS foam, which can be cut to virtually any size or shape to accommodate unique applications or jobsite conditions.

    • Can you put glass block on top of the curb?

      Yes. The USG Durock™ Shower System Curbs can accept the weight of glass block walls. The curbs are made from durable 3-lb. density EPS foam, which has a compressive strength in excess of 60 psi.

    • Can I use another manufacturer’s linear drain with the USG Durock™ Shower System Custom Tray?

      Often times, yes. Consult your local distributor or sales representative.

    • What type of backerboard do I use behind the USG Durock™ Waterproofing Membrane?

      Use only code-approved wall substrate suitable for wet areas, such as traditional backerboards USG Durock® Brand Cement Board or USG Fiberock® Tile Backerboard behind the waterproofing membrane. Or if using an already waterproof backerboard, such as USG Durock™ Brand UltraLight Foam Tile Backerboard or USG Durock™ Brand Glass-Mat Tile Backerboard, the waterproofing membrane may be omitted. Refer to usg.com for backerboard installation instructions.

    • How come USG doesn’t recommend drywall or water-resistant drywall (greenboard) in wet areas behind the USG Durock™ Waterproofing Membrane?

      In 2006, the International Residential Code (IRC) eliminated the use of drywall in areas exposed to direct moisture, such as tub surroundings and shower compartments. This code change, approved unanimously by ICC committee members during the 2003-2004 code cycle, reflects the poor performance record of drywall in wet areas, particularly when used as backing for ceramic or stone tile tub and shower assemblies.

      At USG, we agree with the code change because we believe that the sheathing panels that support a ceramic or stone tile tub or shower assembly should be able to stand up to the rigorous demands of a wet environment. For example, if the water supply lines or a mixing valve were to develop a leak in the wall cavity, and consequently saturate the drywall, the tiled shower assembly could sustain permanent damage. This would not be the case if a code-approved backerboard that’s suitable for use in wet areas (e.g., USG Durock® Brand Cement Board or USG Fiberock® Tile Backerboard) was used as backing to support the tile assembly.

    • What type of mortar do I use to install the USG Durock™ Shower System?

      Use tile-setting mortar meeting one of the following standards: ANSI A118.1, A118.4, A118.11, or A118.15.

    • Can I use the USG Durock™ Shower System with a mortar/mud bed shower base?

      Yes.  Please visit our installation videos to see the mortar/mud bed video installation.

  • Other
    • Do you have a custom shower tray program?

      Yes. We offer a program that helps you design and install near limitless configurations of shower shapes and sizes, up to 64 sq. ft. All of our custom shower trays are manufactured from 3-lb. expanded polystyrene foam (EPS) and are designed specifically to integrate with the USG Durock™ Shower System components. They also include the USG Durock™ Shower System Shower Tray Disk. Large quantities are also available for multi-unit developments. To get started, download our custom tray order form on the Custom Shower Tray page. of this site.

    • How do I order a custom shower tray?

      Visit our Custom Shower Tray page under the Our Products page of this site for more information.

    • Is there a place to buy online?

      Yes. The USG Durock™ Shower System and components can be purchased online The Home Depot, Amazon, Tile This and Contractors' Direct.   

    • I have a unique situation not covered on your FAQs. Whom should I call?

      Call 800 USG.4YOU (874.4968). We're here for you.