Best answer
If you're working over a wood subfloor, cement board is the right choice for your tile base. No matter what you're told at a home center, it's not a good idea to install tile directly over plywood, especially in a damp area like a bathroom.
Do I need to seal cement board before tiling?
Contrary to popular thought, tile and grout are not waterproof, and some moisture will penetrate even if sealant is used. ... However, if you choose to use concrete backerboard, which is much stronger and more durable than gypsum board, a water vapor membrane must be placed underneath it or a sealant applied on top of it.
Do you need to tape cement board before tiling?
2 Answers. The thinset and mesh tape are to strengthen the seams. If you are going to tile over the cement board, you should tape the seams. If you just want to leave the corners untreated that will probably be fine, because that seam won't split the center of a tile.
Do you need to prime cement board before tiling?
Do I need to prime HardieBacker® board before I tile onto it? No. HardieBacker tile backerboard is ready to tile once installed, just wipe down with a damp sponge to remove any dust prior to tiling.
Is cement board needed for floor tile?
In short, tile and grout are not inherently waterproof. Cement backer board is often used as a tile base on plywood or OSB subfloor. Cement backer board on concrete as a subfloor or underlayment is usually not recommended or needed. In most cases, you can apply tile directly to the concrete.1 Dec 2019
How do you lay cement board for tile?
Installing Cement Board Underlayment for Tile
- 01 of 08. Why Use Cement Board?
- 02 of 08. Apply the Mortar Bed.
- Place the First Cement Board Sheet. Lay the first sheet of cement board onto the mortar so the rough side if the board is facing up.
- Fasten the First Sheet.
- 05 of 08.
- Trim the Last Panel.
- Apply Joint Tape.
- Mud the Taped Joints.
Do I need to prep concrete floor for tile?
Before you lay any sort of tile, whether it is stone, ceramic or peel and stick vinyl, you must prepare your concrete floor to ensure that the tiles will go down properly and stay where they're placed. Sweep the floor thoroughly to remove all dust and debris. Rinse the floor in small sections and then blot it dry.
Can you put cement board over concrete?
Technically, cement board can be laid over a concrete slab as the base for a tile installation. ... A better solution is to prepare and resurface the concrete slab so that it can accept thin-set adhesive or a mortar base onto which to lay tile.
Do cement roof tiles need to be sealed?
Like all concrete and natural stone, cement tiles are porous. When installing cement tiles, whether on a floor or wall, they must be sealed before and after grouting to prevent the grout staining the tile.
Can cement tiles be used in a shower?
The most common question is, "Can I use them in my shower or bath?" The answer is definitely, "Yes!" Cement tiles can also be used in wet areas such as the bathroom floor, shower floor, shower wall, steam room or sauna. ... However, do not confuse encaustic cement tile with encaustic tile.
Do you need to waterproof cement board in a shower?
Cement board is not waterproof. Hardibacker is not waterproof. Tile and grout are not waterproof. Cement board will not fall apart when exposed to water.
Related Question Answers

Simon Tewsi
ProfessorHow thick should cement board be under tile floor?
Floors: A 1/4-inch minimum thickness is needed, but thicker panels are also fine. Walls: Use 1/2-inch or 5/8-inch-thick cement board, not 1/4-inch. The extra thickness is needed to span the studs and provide a solid base for the tile.

hiro protagonist
ProfessorDo I need to waterproof cement board in shower?
Here's what the TCNA handbook has to say about the matter: “A waterproof membrane or vapor retarder membrane must be specified to prevent moisture intrusion and protect adjacent building materials.” ~B412 Bathtub or shower with prefabricated receptor. Cement board or Fiber-cement board.

Ricardo Rocha
ProfessorDo I need to seal my concrete floor before tiling?
Although you don't need to install an underlayment between the concrete and the tile, you need to prepare the surface before placing the tile. After all, cracks and uneven areas in the concrete can cause damage to the tile above, and uncontrolled moisture in the concrete can destroy the mortar and loosen the tiles.

skypjack
ProfessorHow do I prepare concrete for tile?
Preparing Cement for Floor TileClean. Start by sweeping your concrete floor to get rid of all dust and debris. Then clean with a wet mop of plain water. ... Dry. Ensure your floor has thoroughly dried before proceeding. ... Level. Use floor leveling compound for large holes or flaws in your cement floor.

Cary Swoveland
ProfessorCan you use cement tiles in a shower?
The most common question is, "Can I use them in my shower or bath?" The answer is definitely, "Yes!" Cement tiles can also be used in wet areas such as the bathroom floor, shower floor, shower wall, steam room or sauna.
...
However, do not confuse encaustic cement tile with encaustic tile..

UnkwnTech
ProfessionalCan I use deck screws for cement board?
It's best to use the cement board screw, but a deck screw will do just fine. ... Use screws designed for cement board like Rock-On screws. They start easier than drywall screws in CBUs. They're easier to use, don't rust as easily and hold better.

Ibraheem Ahmed
ProfessionalDo you need a vapor barrier behind cement board?
You still need a vapor barrier with cement board, although in this case the barrier can go behind the board. Cement board is heavy enough and breathable enough to take the moisture without a problem. By having the vapor barrier behind the cement board you stop the moisture going further into the wall.

Merlin
ProfessionalDo you need green board behind cement board?
Because cement board can be used either for floors or walls, the surface below the cement board will vary: ... In such wet areas, never install cement board directly over drywall or green board. Instead, first, remove the existing surface material, then install the cement board over the studs and membrane, as applicable.

anubhava
ProfessionalDo you need to put a vapor barrier behind cement board?
You should NOT place a vapor barrier BEHIND the backer board. Where, pray tell, would any such collected vapor/water go? Answer:There's nowhere proper for such moisture to egress. The current best practice is to place waterproofing OVER the backetboard and just UNDER the tile.

sariDon
ProfessionalWhat do you put behind cement board in shower?
Cement Board and a Liquid Membrane No plastic sheeting goes behind the cement board.
A liquid waterproofing membrane, such as RedGard or Hydro Ban, is applied to the cement board and allowed to cure.
Then, tile is installed over the membrane..

Kaleb Brasee
UserCan you use cement board in a shower?
In showers, the standard substrate is tile backer, also called cement board or cement backer board. Ceramic and porcelain tile, more than almost any other surface material, needs a stable, flat, flex-free substrate. Even the slightest amount of movement in a building structure can telegraph to the tile and crack it.

Richard Szalay
UserCan you lay tile without cement board?
In either case you use whatever tools are necessary to get it back to a clean subfloor. The second way to interpret your question is, after you've removed and cleaned off the old floor, can you install new tile without backer board. Well yes.

webmat
UserCan you tile directly onto cement board?
Cement backer board is often used as a tile base on plywood or OSB subfloor. Cement backer board on concrete as a subfloor or underlayment is usually not recommended or needed. In most cases, you can apply tile directly to the concrete. Manufactured veneer stone is another use for cement backer board.

Jax-p
UserCan you put cement board over tile?
Cement board forms a durable, stable base for tile, and it has no organic materials (unlike drywall, greenboard, or plywood) so it is not prone to mold, rot, shrinkage, or decomposition due to moisture. Ceramic tile laid over cement board is one of the most durable floor or wall surfaces you can install.

arno_v
UserCan you use cement board as a subfloor instead of plywood?
No. You will need actual subfloor (3/4 osb or ply) below the cement board to support it. And you'll only need cement board if you're laying tile. Cement board alone will be far to soft, among other problems.

hanshenrik
GuestCan you're tile over old cement board?
Undamaged cement backer board does not need to be replaced.
If tile has not been attached directly to the backer board, and it has not been dented or punctured, it can be reused without any special preparation..

vaultah
GuestDo I have to use cement board under Wall Tile?
In short, tile and grout are not inherently waterproof. ... Cement backer board is often used as a tile base on plywood or OSB subfloor. Cement backer board on concrete as a subfloor or underlayment is usually not recommended or needed. In most cases, you can apply tile directly to the concrete.

Richard
GuestDo I need cement board for stone veneer?
Natural stone veneer is heavy and should not be installed over drywall; cement backerboard or masonry applications are recommended.

bobobobo
GuestDo I need to plaster before tiling?
If you sort the plasterboard out level/flat.........you don't need to plaster it at all....... tile directly onto the plasterboard, because if you are not experienced in plastering, you could end up in a worse state. Sort the plaster board, it's not that heavy.......then prime with acrylic primer.......then tile it.

Blankman
GuestDo I need to prime cement board before tiling?
Do I need to prime HardieBacker® board before I tile onto it? No. HardieBacker tile backerboard is ready to tile once installed, just wipe down with a damp sponge to remove any dust prior to tiling.

Waiski
GuestDo you have to replace cement board under tile?
Undamaged cement backer board does not need to be replaced.
...
It is difficult to remove tile from a cement backer board, and even more difficult to avoid damaging the board in the process.
Since backer board is relatively inexpensive, it's not normally worth the time and labor it would take to remove the tile to save it..

Amir Makram
GuestDo you need plywood under cement board?
The Surface Below the Cement Board Flooring: For ceramic tile floors, the cement board usually rests on a plywood subfloor (minimum 5/8-inch-thick exterior-grade plywood or OSB). ... In such wet areas, never install cement board directly over drywall or green board.

Brian Bi
GuestDo you need vapor barrier behind cement board?
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.

Luis Miguel Mejía Suárez
GuestCan I use cement board for shower floor?
Do not use cement board on its own. Your shower will leak and you will be tearing it out within a year.

Derek 朕會功夫
GuestWhy do people tape cement board seams?
2 Answers. The thinset and mesh tape are to strengthen the seams. If you are going to tile over the cement board, you should tape the seams. If you just want to leave the corners untreated that will probably be fine, because that seam won't split the center of a tile.

Drew Reese
GuestDo I need to remove paint from concrete before tiling?
Painted concrete surfaces are a well known bondbreaker for all tile thinsets and self levelling compounds and must be removed prior to installing tile.

David K. Hess
GuestDo I need cement board for kitchen backsplash?
But for a tile backsplash, if your wall is good and plumb, without any major ridges or problems, you don't always need to use a backer board, often you can just apply thinset to the walls and put your tiles in place.

Amila Senadheera
GuestCan I cement my whole backyard?
In general, if you are doing any work which is going to modify your floor plan, then, you do need a permit. If you are going to pour concrete for a patio in your backyard, then, yes, you do need a permit.

RtmY
GuestShould I put plastic behind cement board?
No plastic sheeting goes behind the cement board. A liquid waterproofing membrane, such as RedGard or Hydro Ban, is applied to the cement board and allowed to cure. Then, tile is installed over the membrane.

Dun Peal
GuestDoes cement board in shower need waterproofing?
“A waterproof membrane or vapor retarder membrane must be specified to prevent moisture intrusion and protect adjacent building materials.” ~B412 Bathtub or shower with prefabricated receptor. Cement board or Fiber-cement board. Ceramic Tile. ... Consult local building code for moisture barrier requirements.”

bookcasey
GuestDo I need to seal a concrete floor before tiling?
7. Apply the Sealer. After cleaning, patching, and repairing the concrete floor, you'll be ready to seal it. This process creates a protective layer that prevents moisture from seeping through the concrete and into the tile floor.

Endless
GuestCan I reuse cement backer board?
Undamaged cement backer board does not need to be replaced. If tile has not been attached directly to the backer board, and it has not been dented or punctured, it can be reused without any special preparation.

Jouni K. Seppänen
GuestCan you floor level on cement board?
A self leveling compound can be applied to most types of subfloor materials. You can apply self leveling compound to plywood, osb, concrete, cement board, hardibacker and many other types of subfloor materials. You can also use self leveling compounds when installing tile over top of an existing tile installation.

Eugene Yarmash
GuestCan you glue cement board to concrete?
Most tile professionals, including John Bridge, concur: Attaching cement board to concrete is not an acceptable way to surface the concrete prior to tile installation. Thin-set alone will not help the cement board stick to the concrete slab.

zerkms
GuestCan you put cement board on the floor?
Cement board is a type of underlayment that is now standard for most tile installations, but particularly for floor tile.
The primary benefit of cement board is that it doesn't break down or expand or warp if it gets wet.
This is a distinct advantage over plywood and drywall..

M.Innat
GuestDo I need plywood under cement board?
Because cement board can be used either for floors or walls, the surface below the cement board will vary: Flooring: For ceramic tile floors, the cement board usually rests on a plywood subfloor (minimum 5/8-inch-thick exterior-grade plywood or OSB).

navylover
GuestShould I put cement board under tub?
You don't need any cement board under the tub. It is far more important to have a sturdy layer of ply under the tub.

Darkman
GuestShould I put Thinset under cement board?
Embed the cement board in latex-modified thin-set mortar The main reason for using thin-set between the cement board and the subfloor isn't as much for bonding as it is for even, void-free cement board support throughout the floor. ... Then spread thinset mortar with the flat side of a 1/4-in.

stuartd
GuestIs Durock cement board non-combustible?
This DUROCK® cement board is a non-combustible, water and mold-resistant panel designed for use under tile, in shower areas, and readily applied over ...

JvdV
GuestWhat do you use to seal cement board when tiling?
The thin-set is a cement-based powder that you mix with water or latex additive to form a thick paste, which is used to seal the seams in the board and can also be used to set the tile. Finally, you'll need an 8 x 12-ft. piece of 4-mil plastic sheeting and some straight 2x4s.

P.J.Meisch
GuestDo I need DPM on concrete floor?
Do I need a DPM under laminate flooring? Simply put yes. In order to prevent damp rising through the concrete floor and causing issues, a DPM should be used under all final floor types including wood flooring, laminate, vinyl and floor tiles.

solarissmoke
GuestDo I need cement board for shower ceiling?
It can be, but it's not really necessary. You can tile directly to drywall in any dry area. If your doors go all the way to the ceiling, you might consider cbu verses any kind of drywall on the ceiling, otherwise, it is considered a dry area.

mcsoini
GuestDo you have to glue down cement board?
You cannot put a cement backer board over that. You need to put a layer or plywood, minimum 5/8 IIRC, over those boards, then mortar the backer to the plywood. Those 1x8 boards won't give a solid foundation and will flex. Over time, that will cause tile to pop loose or crack.

GWW
GuestWhat kind of cement do you use for a shower pan?
Floor Mud QUIKRETEQUIKRETE® Floor Mud (No. 1548-81) is a Portland cement based underlayment mortar designed for leveling travertine, slate and marble floor tile, and for shower pan applications.

Tarik Huber
GuestWhere do you put cement board in a bathroom?
Cement backer board is mainly used as a sub-surface for tiling. Cement backer board is often used as a tile base on plywood or OSB subfloor. Cement backer board on concrete as a subfloor or underlayment is usually not recommended or needed. In most cases, you can apply tile directly to the concrete.

Josh Buhler
GuestDo I need to waterproof concrete floor before tiling?
Cement is actually a very porous material and can easily absorb water. Therefore, any concrete that may come into regular contact with water, such as under tile or for a pool, will need to be waterproofed. If cement is not waterproofed, it can cause issues with the mortar used between the tiles.

Potatoswatter
GuestHow do you prepare a concrete floor for VCT tile?
Scrape down as much as possible (preferably all the ridges). Then give it a skim coat with ardex feather finish or equivalent to make everything nice & smooth. Might need to scrape/sand that & do another coat. Vct is a resilient floor.

ephemient
GuestHow much cement and sand do I need for floor tiles?
Mortar calculation for tile flooring We need 1.5 m3 volume of wet cement mortar that means, we need this much volume after adding water to cement and sand mix. Dry volume of mortar is considered as 25% of more of wet volume.

Jan Garaj
GuestCan you use cement tile in a pool?
Can I use cement tiles for my pool? Yes. But you need to seal the tiles with a sealer that is appropriate to withstand pool chemicals. Avente Tile offers NO guarantee in resistance to chemicals.

Andomar
GuestDo you have to put cement board under tile?
In short, tile and grout are not inherently waterproof. ... Cement backer board is often used as a tile base on plywood or OSB subfloor. Cement backer board on concrete as a subfloor or underlayment is usually not recommended or needed. In most cases, you can apply tile directly to the concrete.