All tile
Walls: Use 1/2-inch or 5/8-inch-thick cement board, not 1/4-inch. The extra thickness is needed when spanning the studs and it provides a solid base for the tile. Countertops: 1/4-inch, 1/2-inch, or 5/8-inch-thick panels are all suitable for countertops.
1/4" hardibacker alone is an unsuitable substrate for shower wall tile. If it were attached to properly waterproofed drywall, plywood, or plaster it would be fine. Think about it, one wayward elbow, knee, or hip bump and you may get flexion which would cause the grout (or tile) to crack.
Don't use paper-faced backer board, i.e., paper-faced drywall, behind seamed tub and shower enclosures. Use an alternate approved product such as fiber-cement, fiber-reinforced gypsum, glass mat gypsum, or fiber mat-reinforced cementitious backer panels.
1/4" USG Durock® cement board is an ideal substrate for floor and countertop ceramic tile installations. The 1/4" thickness helps eliminate transition trim when abutting carpet or wood flooring and minimize level variations with other finish materials.
USG Durock Brand Cement Board with EdgeGuard is a strong, water-durable tile backerboard with an enhanced, proprietary edge performance to prevent spinout and crumbling. This mold-resistant tile backer is the perfect choice for floors, walls, countertops, tub, shower areas and exterior finish systems.
Doing this will require that you remove the existing surface material before installing backer board over the studs. Cement board can also be used on countertops when laying tile. However, the process will involve using an extra sheet of backer board. Never use standard screws when installing cement board.
When using a standard cement board for a waterproofed shower enclosure, installers must also apply a liquid waterproofing membrane on the entire wall structure. With PermaBASE WP, they need to apply waterproofing/sealant only at joint seams, fastener heads/penetrations and exposed edges.
For bathroom applications, green board can be used on ceilings and walls where there is no direct water application, such as behind sinks and on bare walls. Only cement board can withstand the wear and tear of a shower or tub enclosure.
Tile installation using GoBoard® by Johns Manville saves you time in all your projects, including mudrooms, bathrooms, entryways or showers. GoBoard® is an ultra-lightweight, waterproof, and durable tile backer board that is easy to cut and install.
What thickness of backer board should I use? Most commonly, cement board underlayment comes in two sizes: 1/4 and 1/2 inch. While either size can be used on a floor the 1/2 inch is the only size recommended for walls. Further, 1/4 inch typically works best for most flooring transitions.
A cement board may be used in a variety of shower settings. All applications use tile boards in conjunction with some form of waterproofing material. Liquid membrane, plastic ing, an uncoupling membrane, or a board that's already waterproofed. A moisture barrier of 4 or 6 mils thick plastic is put over the wall studs.
Provide a 1/4 in. clearance gap between the floor, tub or shower receptor base and the cement board. Do not place cement board into the shower pan mortar bed.
What is a shower tile backer board? A shower backer board can act as a waterproofing barrier in between your shower and the wall. Traditional shower wall boards are made out of Portland cement, and they also come along with fiberglass reinforcements.
Cement boards, like Durock and WonderBoard, are water-resistant…but they are not waterproof. When you are using cement backer boards in a shower or around a bathtub, or really anywhere that is going to get wet, you need to think about waterproofing.
Hardiebacker is significantly lighter than Durock and WonderBoard, leaving this the lightest out of the bunch. How light it instantly makes it one of the most popular brands on the market. Since there isn't any glass mesh in it, unlike Durock, it makes the job much smoother and even minimizes the cleanup.
The conclusion is that cement board is the only product you should be using when there is any chance of contact with water. Many times it's what you don't see behind the walls that has the biggest impact for longevity of your project.
Cement board has a smooth side and a rough side. Face the rough side out if you will be using thin-set mortar adhesive to install the tile but the smooth side out if you will be using latex mastic.
For most interior applications, Durock® Brand Cement Board Panels are not affected by water and do not need to be waterproofed. Durock® is water durable but not waterproof. If you're looking for added protection to water sensitive material behind the Durock®, you may consider adding a waterproofing membrane.
Cement Board and a Liquid Membrane
In this application, cement board is installed directly onto the studs. No plastic sheeting goes behind the cement board. A liquid waterproofing membrane, such as RedGard or Hydro Ban, is rolled onto the cement board and allowed to cure. Then, tile is installed over the membrane.
If it's a cement board, you need a vapor barrier, because cement retains moisture, which means the wood next to it is always damp.
Thinset is going to create a solid surface under tile and prevent flexing that could lead to cracking. Using thinset between the backerboard and subfloor will create additional strength, fill in any potential gaps that exist and lessen the possibility of movement.
The manufacturer dictates to use thinset between subfloor and cement board.