What does backer board do?

Asked By: Anastasija Urgin | Last Updated: 6th March, 2020
Category: home and garden indoor environmental quality
4.6/5 (190 Views . 30 Votes)
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.

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Regarding this, when should you use backer board?

Use backer board for all your tile jobs, including floors, walls and counters. You can also use it for thin exterior brick and stone. Some companies manufacture backer-board sheets with a rougher side for use with thinset mortar and a smoother side for use with ceramic-tile mastic.

Additionally, is it OK for cement board to get wet? Water resistance These Portland cement based products are smaller in size compared with the gypsum core based products. Cement boards should not be confused with gypsum core backer boards. Gypsum core backer boards are affected by water and should not be used on wet exposure areas.

In this regard, what is backing board used for?

The primary purpose of cement boards is to serve as backing for tile and is superior to paper-covered gypsum at this task because of its resistance to water – as tile is typically used in areas prone to water exposure, it is important to have a backing that will not develop mold and mildew or disintegrate after

Where can you use backer board?

You always want to install backer board behind showers and the walls surrounding bathtubs. Backer board is also used under floor tile when there's a wood sub-floor. This includes bathroom floors and any other tile flooring in your house, what builders call the “wet areas”.

39 Related Question Answers Found

Do you need to seal Hardibacker before tiling?

To Seal or Not To Seal
Contrary to popular thought, tile and grout are not waterproof, and some moisture will penetrate even if sealant is used. If you decide to go this route, no sealant will need to be applied on top of the backerboard, as this could trap moisture between the two layers of waterproofing.

What thickness backer board should I use?

Cement backer board comes in two standard thicknesses, 1/2 inch and 1/4 inch. The industry standard is to use 1/2-inch-thick backer board on wall tile installations, such as a tub surround.

Which is better durock or Hardibacker?

HardieBacker board is definitely the go-to choice when it comes to tiling and counter tops. The Durock board is abrasive and can damage certain surfaces—particularly porcelain, vinyl, and enamel–whereas HardieBacker does not contain any abrasive materials and is, therefore, the preferable board for underlaying.

Do you have to use thinset 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. It does not sound as if you have a quality-minded contractor.

Do you need to waterproof cement board before tiling?


So, if you're looking for durability and strength, concrete backer-board will probably be your choice. First, you should provide a waterproof/resistant membrane against the wood studs before installing the concrete backer-board to protect the wood studs from moisture absorbed through the backer-board.

Is Hardie backer waterproof?

cement backer board is not waterproof,but water cant hurt it,even when soaked in water for months or even years

Do I need to use backer board when tiling?

In short, tile and grout are not inherently waterproof. 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.

Do 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.

Should I use cement board under tile?

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.

How thick should cement board be for tile?


Cement-fiber, or similarly reinforced, backer board comes in standard 1/4 inch and 1/2 inch thicknesses. If you're installing backer board over an existing subfloor, 1/4 inch is sufficient. If you're installing backer board in new construction, attaching it directly to floor joists, opt for 1/2 inch sheets.

What is the best backer board for tile?

Tile Backer Board Breakdown
  • Foam boards are lightweight, easy to cut, and a completely waterproof. Pictured: Wedi Board tile backer board.
  • Schluter approves Kerdi over drywall.
  • Hardibacker is the best known fiber cement board.
  • Cement board has improved over the years and is easier to work with.

What is the difference between drywall and cement board?

Whereas drywall comes in 4-by-8 sheets, cement board comes in 3-by-5 sheets. Drywall panels fit between wall studs spaced 16 inches or 24 inches apart.

Can I use 1/4 cement board on floors?

Floors. 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.

Is cement board fire rated?

Yes, HardieBacker® 1/4" Cement Board is deemed noncombustible when tested to ASTM E 136 and can be used in conjunction with other noncombustible materials around a fireplace. This does not mean that clearances to combustible building materials can be reduced by using HardieBacker 1/4".

Can cement board be used below grade?


Can USG Durock® Brand Cement Boards be used on the interior and exterior of buildings? Yes. They can also be used in below-grade applications such as basements. Below grade in this application does not include direct ground-contact applications.

Can I tile over drywall?

Sheetrock, or drywall, is no different for tiling over than wood, plaster, cement, or other wall materials. If you are tiling an area that is not in a bathroom, tiles can be applied directly to the sheetrock simply and easily. The wall has to simply be prepared in order to complete this task properly.

Can you skim cement board?

You can't skim finish plaster to a depth of 10mm, the average skim coat is 2-3mm thick you can go slightly thicker but I wouldn't advise more than 5mm. Hardi say you can skim their cement boards but Aquapanel say you must use their own special & probably expensive plaster.