Best answer

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.

Answered by: David Jacquel Date created: Jun 24, 2022

Do you have to waterproof cement board?

Asked By: brentonstrine Date created: Jun 15, 2022

Most concrete backer-boards on the market today are not water-resistant, but all are waterproof. Since many people confuse the terms, it is a common misconception that this is the best material for use inside a shower or tub area.

Answered By: Soc Date created: Jun 18, 2022

Can you put cement board over concrete?

Asked By: Gregory Pakosz Date created: Jun 16, 2022

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.

Answered By: matt Date created: Jun 18, 2022

Can you put cement in wet ground?

Asked By: Tony Andrews Date created: Jun 14, 2022

The water in the hole under the pipe can be sucked out with a wet-dry vacuum before and during the repair job.

Answered By: Carsten Massmann Date created: Jun 14, 2022

Do you have to use thinset under cement board?

Asked By: Christofer Weber Date created: Jun 18, 2022

No Thinset underneath the backer board “The thinset goes ON TOP of the cement board to stick the tiles!” ... Cement board is a different product and it needs to be installed in its own way. Additionally, screws don't take the place of thinset either.

Answered By: Xeo Date created: Jun 18, 2022

How thick should cement board be under tile floor?

Asked By: mfulton26 Date created: Jun 08, 2022

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.

Answered By: Alex Fleischer Date created: Jun 09, 2022

Do you need plastic behind cement board?

Asked By: GollyJer Date created: Jun 18, 2022

Their online instructions/diagrams show no use of a vapor barrier. You should, so that any moisture that gets behind the cement board runs into the tub or shower instead of into your wall cavity (causing rot or mold/mildew).

Answered By: Xenph Yan Date created: Jun 20, 2022

Do you need to put a vapor barrier behind cement board?

Asked By: Chris Baker Date created: Jun 17, 2022

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.

Answered By: Steven C. Howell Date created: Jun 20, 2022

Is Thinset under cement board necessary?

Asked By: kqw Date created: Jun 22, 2022

Not only is thinset a critical component underneath cement board but the other critical component is the fasteners. And you won't have the fasteners if you are trying to install it over concrete.

Answered By: TWiStErRob Date created: Jun 24, 2022

What do you put behind cement board in shower?

Asked By: matt wilkie Date created: Jun 09, 2022

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..

Answered By: Rok Kralj Date created: Jun 09, 2022

Can I use 1/4 cement board on floors?

Asked By: MaxU Date created: Jun 08, 2022

Both 1/4- and1/2-inch cement board are appropriate for floors. To install cement board on floors, cement board manufacturers mandate a 5/8-inch plywood subfloor or OSB underlayment.

Answered By: Omri Attiya Date created: Jun 08, 2022

Related Question Answers

casper.dcl

Professor

Do you put cement board under a shower pan?

Once the subfloor of proper thickness is properly installed then you can apply cement board directly to the subfloor material. ALL CEMENT BOARDS MUST be installed in a fresh bed of thinset. ... If you want the cement board under the shower tray then do so - doesn't matter.

Grr

Professor

Can you glue stone veneer to cement board?

What can I put stone veneer on for an interior application? For interior applications, stone veneer can be installed over cement board, drywall, and all of the above.

Henk Mollema

Professor

Can 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.

exebook

Professor

Can you put cement over silicone?

Yes, silicone will stick to cement board.

In fact I highly recommend that you use cement board such as 'Durock' as your backer board.

Use proper screws.

Such as the specific cement board screw..

Michael Liu

Professor

How do you fill gap between cement board and tub?

Technically, after the tile is installed over the backer board that gap between it and the tub ledge should be filled with an ASTM C920 sealant (caulking e.g. silicone). Although some say you should have weep holes along this gap so any water behind can weep out into the tub.

Slaw

Professional

Can you use 1/4 inch cement board walls?

1/4" Durock cement board should not be used for wall or ceiling applications. For wall or ceiling applications, use 1/2" or 5/8" Durock cement board. If you have 3/8" sheetrock, use 1/2" cement board and feather out the joint to approx 10" to 12". It should be almost unnoticeable if done right.

Sudipto

Professional

Do 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.

AD7six

Professional

Do 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.

Murli Prajapati

Professional

Do 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..

domsson

User

Do 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.

fmw42

User

Do you need Thinset under cement board?

Not only is thinset a critical component underneath cement board but the other critical component is the fasteners.

And you won't have the fasteners if you are trying to install it over concrete..

Gray

User

Does cement board go over lip of shower pan?

The best approach when installing cement board or other tile backer around a tub is to keep the cement board out of the lip area.

Apply it to the wall with the bottom edge about 1/4 in.

above the lip of the tub.

...

Fill the gap between the tile and the tub with caulk..

Arup Rakshit

User

Does cement board need to be sealed?

While you don't always need to seal backer board, it sometimes make sense to do so. If you are installing backer board in an area that will be subject to a great amount of moisture, like in a shower, then it makes sense to put a waterproofing sealer on it.

dustbuster

User

Does silicone stick to cement board?

Yes, silicone will stick to cement board. In fact I highly recommend that you use cement board such as 'Durock' as your backer board. Use proper screws. Such as the specific cement board screw.30 Sep 2015

stefan

Guest

How thick of a concrete slab for a hot tub?

about 4 inchesConcrete Slab The base of reinforced concrete should be about 4 inches thick and be able to withstand a weight of at least 115 pounds per square foot, especially for larger spas. The concrete should be fully cured prior to placing the tub.

rintaro

Guest

What thickness cement board should I use?

Half-inch cement backer board is ideal for most tiling jobs, including walls, floors, countertops, and ceilings.

For flooring, the backer board should be installed over a 5/8-inch thick OSB or plywood base..

vals

Guest

Can you put a hot tub on a concrete slab?

A level concrete pad or a reinforced deck are the most common surfaces hot tubs are installed on. However, depending on the spa model you use, you may not need to pour concrete. ... Talk to your hot tub dealer about the specific foundation requirements for your spa model.

Traxo

Guest

Will silicone adhere to cement board?

Yes, silicone will stick to cement board. In fact I highly recommend that you use cement board such as 'Durock' as your backer board. Use proper screws.

omajid

Guest

Do 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.

Rich Bradshaw

Guest

Does cement board go over tub lip?

The best approach when installing cement board or other tile backer around a tub is to keep the cement board out of the lip area. Apply it to the wall with the bottom edge about 1/4 in. above the lip of the tub. ... Fill the gap between the tile and the tub with caulk.

joaquin

Guest

What do you do with a gap between tub and cement board?

Caulk the gap Ideally, you would leave a 1/8 inch gap which would then have the sealant applied to it. Either stopping the cement board above the tub flange or alternately shimming it out and dropping it down near the tub would both be good options.

Ted Lyngmo

Guest

Is a vapor barrier necessary behind cement 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. ... You should NOT place a vapor barrier BEHIND the backer board.

PsyGik

Guest

Should 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.

Paul Hiemstra

Guest

Can you put footings under concrete slab?

edit - To put footings under the slab, you can cut holes wherever needed, excavate for footings (Sonotubes or concrete piers or similar) and then patch the concrete slab.

planetp

Guest

Can 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.

Chris Lawlor

Guest

Do 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).

James McNellis

Guest

Do you have to put Thinset under cement board?

No Thinset underneath the backer board “The thinset goes ON TOP of the cement board to stick the tiles!” ... Cement board is a different product and it needs to be installed in its own way. Additionally, screws don't take the place of thinset either.

ericsoco

Guest

Should 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.

jameshfisher

Guest

Should you put 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.

Phil Ricketts

Guest

What do you put on seams of cement board?

Use special mesh tape on seams Cut drywall to fill in between the existing wall or ceiling and the cement board. Screw the drywall to the studs. Cover all of the corners, joints and seams, including the joint where drywall and cement board meet, with the fiberglass mesh tape.

Ivan Chernykh

Guest

What is the best insulation for under a concrete slab?

Applying a bead of polystyrene-compatible caulk or mastic to the top of the insulation board minimizes water infiltration behind it. For under-slab applications, the rigid foam insulation typically should be installed over a gravel base, with a poly vapor diffusion retarder between the gravel and insulation.

harto

Guest

Is 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 ...

smwikipedia

Guest

What do you put under a concrete driveway?

Use wire mesh for driveways that are 4 to 5 inches thick, and rebar for those that are 5 inches or more. Place rebar in a grid pattern with a spacing between bars of approximately 12 inches. In either case, blocks should be used under the reinforcement to keep centered within the concrete.

Laurence Gonsalves

Guest

Do 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.

Alfred Huang

Guest

Can you mix cement in a plastic wheelbarrow?

Whether you hand mix concrete in a plastic tub, homemade mixing tub or wheelbarrow, the technique is the same to find the right concrete mix ratio. However, it's easier to move and dump concrete that's mixed in a wheelbarrow.

Alvaro

Guest

Can you store cement in a bucket?

Place the bag in an airtight tub or buy premix concrete in a bucket. If you need to store a bag of premix concrete, you should put it in an airtight plastic container. Even if the bag is not open, the relatively porous material of the bag can let in air and moisture, allowing the mix to age.

prehistoricpenguin

Guest

Can you caulk cement board in shower?

In the event the caulk seal between the bottom row of tile and the tub/shower fails, water can get behind the tile. If the backer board is touching this ledge, it will readily soak up this water like a sponge. ... Then, before installing the tile, apply a bead of pure silicone caulk between the backer board and the ledge.

Kamal Nayan

Guest

Do 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.

Mike

Guest

How much space should be between cement board and tub?

1/4"The backer board should overlap the tub flange so the tile has a stable backing to attach to. This requires shimming the backer board out from the studs so the wall is plumb. There should be a 1/4" gap between the tub ledge and the backer board.

parliament

Guest

Where 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.

Audrius Meskauskas

Guest

Do 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.

Pavneet_Singh

Guest

Do I need cement board under floor tile?

If you're working over a wood subfloor, cement board is the right choice for your tile base. ... Because plywood expands and contracts beneath the ceramic tile, grout and tile failure (loose tiles and cracked, crumbling grout) is just a matter of time.

Andrey Nikolov

Guest

Can I just screw down cement board?

Put thinset beneath your backerboard. And put your dog out. Once you have the area fully covered with thinset you can lay your backerboards into the bed of thinset and screw it down. DO NOT use drywall screws!

g.pickardou

Guest

Do you need to use thinset under cement board?

Not only is thinset a critical component underneath cement board but the other critical component is the fasteners. And you won't have the fasteners if you are trying to install it over concrete.

Håken Lid

Guest

How high should cement board be in shower?

Start installing your boards a quarter inch above the floor, tub, or shower board and caulk accordingly. 2. Fasten cement board with specified nails or screws, a maximum of 8” on center at all supports.