There’s no shortage of choices when it comes to selecting a backer board for tiling jobs. For many folks, it’s like picking a house’s foundation. You don’t see it once the job is finished but it determines how long-lasting and attractive your tiled shower wall will be.
Durock Versus Wonderboard Or Hardiebacker
Why Substrate Choice Matters
Here’s a quick rundown on the big three: HardieBacker, Durock, and Wonderboard. All three have their strengths and there weaknesses; and all have devoted followers. Contractors and DIYers consider all of these substrates alike.
Wrong. Each has unique properties: weight, how easy it is to cut, and how it take on moisture. A little homework will help you choose what’s best for you and save you time, sweat and perhaps future headaches.
Durock Cement Board Pros and Cons
Look for a material that is easy to cut, resists water, stays flat and provides a way for your thinset mortar to grab onto. The good thing about Durock cement board is that it’s solid. It’s heavy, it’s thick, and it feel substantial in your hand.
The bad thing is that it’s too heavy. You really need to pay attention when you are hanging this on a wall. Make sure you space your studs correctly.
Pay attention to what type of fastener you’re using. Use the wrong sized screw or forget a screw somewhere and that board will sag. And when that board goes down, you’ll have lippage in your tile, which not only makes your shower look terrible but allows water to get behind the tile in an uneven gap.
Durock is actualy made from cement. This makes it completely impervious to water, though it’s not waterproof on its own. Leave it underwater for weeks at a time and it won’t be damaged.
You still has to get the seams taped and mortared well. The only real problem with Durock is how dusty it is. When cut, it produces a fine, dry powdered cement that coats every surface in your shop.
It gets all over your tools and in your lungs. Use a proper respirator (not a dust mask) or you’ll be sorry come quitting time.
Wonderboard Fiberglass Mesh Issues
Instead of cement board as used in Durock, Wonderboard uses a cement core with a fiberglass mesh face.
This reduces its weight versus Durock making it more manageable for an individual to install. Theoretically this should improve adhesion of the mortar to the mesh face; however, that mesh is what complicates cutting. Because those fibers are hard, they’ll eat up your blade fast.
You want a diamond blade saw (a standard carbide tile cutter won’t make the cut) and you’ll hear your saw’s motor work harder then it does when cutting through other boards. Now here’s another thing about using Wonderboard: It looks good. But only when used properly.
The issue arises with the fiberglass because if you don’t apply thinset and mesh tape over the exposed edges the board will wick water up and ultimately delaminate. You’ll have a nice looking white surface on one side, but the back will be separated from the board. And that’s what folks miss on this.
They see that nice white surface and think it’s protected. It isn’t. Sealing seams correctly is required with Wonderboard.
HardieBacker Balance of Weight and Ease
In-between is HardieBacker. It’s a bit like the Durock, but it’s a bit light, and cuts more easiler than the Wonderboard. And it doesn’t have the fiberglass mesh side that makes cutting such a nightmare.
I’ve found it works reasonably well with just a regular carbide blade (although it will go faster with a diamond), and it’s what people use because it seems to be right in the sweet spot between durable enough and easy to handle. It’s not heavy like Durock, nor does it fight back like Wonderboard with its fibers. But there are a few caveats: You need to prepare the HardieBacker for sticking a little more than other surfaces.
It’s very slick (too slick in many cases for some mortars to grab hold right away). Scoring the face and/or applying a polymer-modified thinset is something that many pros suggest. Without one of these two options, you could have tiles coming off after a while if you use an ordinary unmodified mortar.
It is just another detail but it makes a difference. A good bond is your best defense against water entry. Most homeowners make their decision based off weight.
Durock can put more stress on the existing framing than necessary, especially if this is a retrofit project and the existing framing wasn’t built to handle a heavy load. The lighter board options of Wonderboard and HardieBacker places less stress on your studs. In a small area where it’s inconvenient to be trying to maneuver heavy boards around, the lighter options are the winner by default.
Final Recommendation Based on Your Needs
In conclusion: Use what you are comfortabley using and what works in your installation situation. If you don’t care about dust or the weight of the board but want something very stiff, use Durock. If you hate fumbling with cutting but like how well it adheres then go with Wonderboard.
And if you like being somewhere in the middle and want something reasonably easy to work with, use HardieBacker. Choose the right board based on your tolerance for grunge and your tools and get it installed properly. Tile is the skin.
Board is the muscle.