Do you need green board 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.

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..

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.

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.

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..

You can also use a carbide tipped cutting tool similar to a utility knife to cut the cement board. Use a compass to draw the hole and use the cutting tool to score the board on both sides, then pop it out with a hammer.

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.

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.

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..

Natural stone veneer is heavy and should not be installed over drywall; cement backerboard or masonry applications are recommended.

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.

Undamaged cement backer board does not need to be replaced.

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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..

Stagger all HardieBacker cement board joints. Do not align with subfloor joints. Never allow all four corners of boards to meet at one point. We recommend an 1/8 in gap between board edges.

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.

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..

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.

The backer board will burn out eventually. You also need to build an insulated heat riser for best performance. A bell around/over the heat riser cannot be cement board as the heat in parts of that will be much too intense.

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.

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

Do not use cement board on its own. Your shower will leak and you will be tearing it out within a year.

The backer board will burn out eventually. You also need to build an insulated heat riser for best performance. ... You want to use brick or other heat resistant thick masonry for the bells. A bell around/over the heat riser cannot be cement board as the heat in parts of that will be much too intense.

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.

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.

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.

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.

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.

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.

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.

“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.”

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.

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.

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).

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.

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.

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.

Whereas drywall comes in 4-by-8 sheets, cement board comes in 3-by-5 sheets. ... The smaller dimensions of cement board make the installation of it on large walls more difficult, but cement board panels fit vertically in 3-foot wide showers, or horizontally behind a standard 5-foot bathtub.

If an existing plaster wall is in good condition – smooth and without major cracks or chips – then you probably don't need to have it skimmed. If you've attached plasterboard, or drylining you have the choice of either painting or decorating straight onto the board, or finishing with a layer of skim plaster.

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.

Do not use cement board on its own.

Your shower will leak and you will be tearing it out within a year..

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.

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.

Acrylic paintFor cement boards that have already been primed, 100% acrylic exterior paint is recommended. Acrylic paint is the best choice for cement board. It's especially important if you are working with new cement board to avoid oil-based primer.

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.

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.

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.

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.

The simplest way to cut cement backer board is to score the surface and snap the sheet along the scored line, similar to the way you'd cut drywall. In fact, you can use a drywall utility knife to score backer board, but a better option is a carbide-tipped scoring tool.

The concrete is unaffected by any water that manages to get behind the ceramic tile. But these concrete products are heavy, problematic to cut and can wick water, causing wood rot. ... If you use cement backer board, you have to install a separate moisture barrier between the board and any wood it's attached to.

every 8 inFasten HardieBacker cement board with specified nails or screws (as listed in “Materials Required") every 8 in over the entire surface. Keep fasteners between 3/8 in and 3/4 in from board edges and 2 in from board corners.

Whenever installing tile in any area of your house, you need a special substrate, or base layer. 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.