What kind of tape do you use for Hardibacker?

Asked By: Yuxiang Indakoetxea | Last Updated: 8th February, 2020
Category: hobbies and interests woodworking
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Hardibacker 500 inside showers will be taped with Alkali Resistant Mesh tape and thinset. Hardi outside of showers will be taped with ARM tape and joint compound (and textured with all purpose joint compound). –Hardi says not to use paper tape—alkali environment will destroy it. You must use ARM mesh tape.

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Just so, what tape do you use for Hardibacker?

This QEP Backerboard Seam Tape Roll is self adhering to reduce application time. Can be used for seaming most types of cement backer board and tile underlayment. Fiberglass mesh for added strength.

Beside above, does backer board need to be taped? For tile backer board such as Durock, Wonderboard, Hardiebacker, Permabase, and others the seams between the board need to be treated with 2-inch alkali resistant mesh tape. Sometimes tiles will pop loose where there's movement. Sometimes it allows an unimpeded way for water to get behind the board and into the wall.

Beside this, do you have to tape seams on Hardibacker?

2 Answers. The thinset and mesh tape are to strengthen the seams. If you are going to tile over the cement board, you should tape the seams. 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.

Why tape a Hardibacker seam?

The fiberglass tape reinforces and strengthens the joint. It can make the difference between cracked or intact tiles over the joints. That should be a big enough deal to make taping worth the effort. You should use alkali-resistant CBU tape because the alkali in the thiset can degrade regular fiberglass drywall tape.

35 Related Question Answers Found

Do I need to seal Hardibacker?

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.

Do you need to tape drywall behind tile?

If you're working with new drywall, there's no need to tape the drywall joints. Seal the walls with a skim coat and let it dry thoroughly. Thoroughly vacuum the area and give the wall a once-over with a damp sponge or cleaning cloth. Allow the area to thoroughly dry before beginning tile installation.

Can I use drywall mesh tape for cement board?

No. The Mold-X10 fiberglass mesh tape is made for drywall seams and intended to be coated with joint compound. FibaTape's Cement Board Tape is the product for cement board. The alkali-resistant coating protects the fiberglass from degradation that can occur with thin-set mortar.

How do you seal a durock joint?

How to Tape Durock Joints
  1. Wipe dust and debris from the joints between the Durock panels.
  2. Cut fiberglass mesh tape to fit in a single layer over every joint where the panels meet, but do not overlap the tape.
  3. Mix powdered latex-reinforced cement mortar with water as directed on the package in a clean plastic bucket.

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

Does Hardie board need waterproofing?

Passing ANSI 118.10 for waterproofness, HardieBacker® 500 Waterproof Cement Board protects tile installations and wall cavities from moisture penetration, eliminating the need to spend extra time applying waterproof coating across the entire surface area of your wall project.

Can I lay tile directly on plywood?

While you can lay tile directly over a concrete slab using thin-set adhesive, don't make the mistake of applying tile directly to a plywood subfloor. Even if you use a waterproof underlayment membrane, the floor will still be either 1/4″ or 1/2” higher than the subfloor, plus the thickness of the tile and adhesive.

Can you use joint compound on Hardibacker?

Texture can be applied to HardieBacker board in the same way as drywall. Use drywall joint compound, not thinset. If finishing to a smooth wall, i'd skim coat the entire board.

Is Thinset waterproof?

As Jason described, thinset itself isn't waterproof. It isn't degraded by water, and does resist the flow of water (somewhat), but definately does not "waterproof" any tile installation the way a membrane will.

Do I need to waterproof shower walls before tiling?


Prepping for shower tile is different than the prepping for tile on drywall. A shower is considered a wet application, so you need to waterproof the foundation, which you'll learn how to do in these instructions. After the waterproofing step, the instructions are the same as if you were installing tile on drywall.

Can you tile over RedGard?

You''ll be fine with thinset over Redguard on walls. It's recommended for waterproofing niches, shelves, and entire shower walls when tar paper or poly are not used as a vapor barrier behind the CBU.

How do you install Seagard seam tape?

Once the mat is installed, apply thin-set mortar into the top of the uncoupling mat where the seam tape will be applied. Using the flat side of a trowel or a taping knife, embed the RedGard® Seam Tape into the still wet thin-set.

Which side of Hardibacker board goes down?

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 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.

How do you fix an uneven backer board?


You do this by making sure the framing to which you attach the cement board is even and by finishing the seams with mortar.
  1. Provide support behind seams that run parallel to wall framing.
  2. Use extra fasteners on seams that are separating.
  3. Repair uneven seams with mortar.

How do you transition from cement board to drywall?

The joint between cement board and greenboard is similar to the joint between two pieces of cement board or two pieces of drywall.
  1. Plan the installation so the last column of tiles overlaps the joint between the cement board and the greenboard if possible.
  2. Mix the thin-set mortar according the instructions on the bag.

Can you install cement board over drywall?

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.