How much space should be between cement board and wall?


Leave a 1/4-inch gap between the backer board and the wall. Leave a 1/8-inch gap between each backer board sheet. The corners and edges of the sheets should not touch one another.

Should cement board go over tub flange?

ANSWER. ANSWER – No there should not be a gap between the top of the bathtub flange and the backer board on the wall. There should be a moisture barrier behind the backer board that is installed in a weather lapping manner starting at the tub flange working up the wall.

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

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. Then apply a generous amount of thin-set to the bottom bathtub tile and position it 1/8 in.

How do you fill gap between cement board and drywall?

For best results getting a good finish between cement board and drywall, use a setting-type joint compound. This product produces a better finish over mesh tape than all-purpose joint compound. Apply 2–3 coats of joint compound to the seam between wall boards. Wait at least 24 hours between coats of joint compound.

Do I need to seal cement board before tiling?

Although most backerboards currently available won’t fall apart when exposed to moisture and are somewhat water-resistant, they aren’t waterproof. To prevent moisture from seeping through to the wood or metal studs beneath the tile, a barrier or sealant must be used on porous materials.

What goes behind cement board in shower?

Use an appropriate waterproof or moisture-resistant backing material behind grouted tile or stone or segmented plastic or fiberglass tub and shower surrounds. Appropriate materials include cement board which has a cementitious core and glass mats on both sides to strengthen the board.

What do you put on seams of cement board?

Quote from the video:
Quote from Youtube video: And he said on the one side so we're just going to put that on you want to make sure all your cement board joints have cement board tape on them doesn't matter if some of the cement board tape

Can I put cement board over drywall?

You should never put a cement board over drywall because water can go through them. Drywalls have poor water resistance and can get mold problems easily. That’s why it’s best not to use them in showers.

Can you finish cement board like drywall?

Durock Cement Boards are a type of drywall reinforced with cement for a harder surface. This type of wall material can be finished just like ordinary drywall, using joint tape and joint compound.

How do you fill gaps in cement board?

Use nails or screws as temporary spacers to create a 1/8-in. gap between sheets of cement board. When you squeeze the thin-set mortar into this gap, it will lock the two sheets together and strengthen the seam. Finally, leave extra clearance around each piece by deducting about 1/4 in.

Do you have to put drywall behind cement board?

(Some cement board products may not require the underlying membrane if the seams are properly waterproofed.) 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.

Does joint compound adhere to cement board?

When using drywall compound over cement board, it is recommended, but not required, to use a faster setting-type joint compound (45 or 90 min), than typical joint compound. Make sure to follow manufacturer guidelines for the products used to finish the non-tiled area.

Do you tape and mud durock?

For tile backer boards such as Durock, Wonderboard, Hardiebacker, Permabase, and others the seams between the board need to be treated with 2-inch alkali-resistant mesh tape. Then a coat of thinset gets flat troweled over the seam. What this does is tie the two boards together and help prevent flexing.

Can cement board be patched?

Patching Cement Board and Green Rock

Just fill large gaps with cement for patching holes. In the case of fiber cement board, it’s best to use thinset mortar, but if you’re replacing drywall, you can use powdered patching compound which hardens after you mix it with water. Let the patches harden before proceeding.

Do you mud cement board?

The correct way to “mud the joints” is going to be to use tile thinset and a fiberglass tape made for cement board. It’s similar to the sticky fiberglass tape made for drywall, but its thicker and more abrasion resistant since the thinset has sand in it and can be vary abrasive.

How do you repair a hole in the fibro wall?

Quote from the video:
Quote from Youtube video: You can patch small holes using a filler. However it should be applied sparingly.