Should I Put Thinset Under Cement Board?

Is Thinset required under backer board?

Thinset is absolutely required beneath backer-board on a floor.

Also, backer-board provides no structural strength at all.

You can not install it directly over a 1x subfloor; that is way too thin and will deflect..

How much thinset do you put under Hardibacker?

This is probably because at one time the installation instructions for Hardibacker called for 3/32″ inch of thinset underneath. Currently, Hardibacker calls for either 1/4″ thinset, or 5/32″ mastic underneath. I always use 1/4″ trowel for all my underlayment and 3/8″ for almost all my tile.

Can I put Thinset on plywood?

Use Thinset With a Higher Latex Content Thinset is the wet base that you first trowel on the plywood to make the tile stick. Higher latex content is essential for bonding to plywood. A quality. One example would be to use Laticrete’s 317 thinset mixed with Laticrete 333 liquid latex additive.

How long should cement board screws be?

Cement board attached to plywood or similar underlayment will hold with only 1 1/4-inch screws; for thick or heavy metal fixtures, use 1 5/8-inch screws. In general, 1 1/2-inch galvanized nails will hold the board firmly in place.

Can I use thinset on cement board?

Use thin-set mortar when installing cement backerboard. Thin-set dries slowly, allowing you to fix and readjust backerboard sheets as needed. With the smooth side of a 1/4-inch notched trowel, spread enough mortar for one sheet.

Why do I need Thinset under backer board?

The thinset is not meant to ‘stick down’, adhere, or otherwise attach your backerboard to your subfloor. It is simply put in place to eliminate voids beneath your backerboard. Once laid into the thinset bed the floor becomes a solid, fully supported substrate for your tile – that’s what you want.

Does cement board need to be waterproofed?

Cement board is not waterproof. It absorbs moisture as well, but it has excellent drying properties.

Can you tile directly onto cement board?

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.

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.

What is the best backer board to use in a shower?

Cement boardCement board is a good, reliable backer board that works well on both floors and walls. Keep in mind that most tile setters err on the side of caution and brush a waterproofing membrane on top of cement board when it is in wet areas like showers or tub surrounds.

What do you put under Hardibacker?

We recommend an 1/8 in gap from board edges. Apply a supporting bed of dry-set mortar or modified thinset to plywood with a 1/4 in square-notched trowel. Mastic can also be used with a 5/32 in V-notched trowel.

Can you use 1/4 inch cement board on floors?

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.

Is cement board stronger than plywood?

If you compare the two configurations using identical thinset mortars, tiles installed over cement backerboard have greater shear-bond strength than those that are installed over plywood. …

Which side of cement board goes up?

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.

Do I need vapor barrier behind Hardibacker?

You need to install a vapor barrier to the studs at the very least, and you must alway mud and tape the seams with fiberglass cement backerboard tape. Backerboard is water-permeable, and will not stop moisture from entering the wall cavity.

Do you have to tape cement board before tiling?

If you are going to tile over the cement board, you should tape the seams. This should not be that difficult. Pack in thinset, lay on the tape, and flat-knife to get it set in. … 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.

How long does it take for thinset to dry under Hardibacker?

I looked at the hardibacker website and and instructions and it doesn’t state how soon you can lay tile after you install the hardibacker. Since it requires a mortar underneath the backerboard, do you have to wait 24-48 hours for it to cure before you can start laying tile on top of the hardibacker?