Kerdi Board vs Durock Breakdown

Brian Jeffries

December 24,2022

Brian Jeffries, a seasoned BPA Advisor. Brian is dedicated to sharing his wealth of knowledge on construction projects and materials. With a focus on architecture and building envelopes, Brian contributes valuable insights that shape the discourse around innovative construction practices and materials.

It’s vital to select the right materials for your project. Even if this means that you have to do extensive research, it will all be completely worth it in the end. However, what about materials that are considered similar or at least have similar functionality? Plus, which materials are the best to choose? To a degree, this could be said about Kerdi Board vs. Durock. 

These two materials do share the same purpose (to a degree), but they’re not exactly the same. It’s important to have a general understanding of these materials, as this is going to make an impact on your project. So, which is the best one to use for your project? You’ll find all the answers here, so continue reading on!

Kerdi Board vs. Durock: Are They the Same?

These two are not the same products, although they do offer some similar functions. Kerdi board is made from foam, while Durock is a type of cement board. They are, however, both used for high moisture areas such as bathrooms, floors, and kitchens.

When Do You Need To Use the Right Type of Board?

One common misconception is that Kerdi board could be used as a substitute for Durock. However, this is far from the case. Kerdi board shouldn’t entirely substitute concrete backer board underlayment. Many contractors will instead use a CBU (such as Durock) with Keri board together.

Is There a Difference Between Kerdi Board vs. Durock?

When it comes to Kerdi Board vs. Durock, how do these two differ? Well, it’s all going to be about the qualifications, so let’s take a closer look at the two materials.

Durock Qualifications

Between the weight from Durock vs. Kerdi board, Durock is going to be by far the heaviest. You can expect this from a cement board. This is going to be more difficult to maneuver and potentially messy too. Plus, since it’s so abrasive, it's not ideal to use this with vinyl or porcelain.

Kerdi Qualifications

Kerdi board is made from extruded polystyrene foam. It’s actually created to mitigate some of the flaws that most cement boards have. It’s often favored because it can handle large amounts of moisture and not mold. So this is commonly used as a waterproof barrier. Plus, since this is made from foam, it’s very lightweight, meaning it’s easier to install for a project.

Kerdi Board vs. Durock: The Benefits

Both of these products offer something unique that could be used for renovation projects. Let’s dive into the benefits that both of this offer.


Kerdi Board vs Durock
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The biggest benefit that Durock offers would be that this can be used for internal and external projects. This alone makes it very versatile.

Kerdi Board

Kerdi Board vs Durock
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One of the largest benefits that Kerdi Board offers would be the fact that it’s not only lightweight, allowing it to easily be used for projects, but this is also water and vapor-proof too. When it comes to home improvement projects, many homeowners and contractors like to use a cement board and combine it with Kerdi. This allows the best of both worlds!

What are the Major Differences Between Durock and Kerdi Board?

There are a few key things that make Kerdi board very different from Durock, so let’s check them out.

Fire Resistance

The cement board is fire-resistant, and since Durock is a cement-based board, it’s going to be fire-resistant, unlike Kerdi board.

Ease of Installation

Unlike Durock, which is very heavy, Kerdi board is quite lightweight. A single person could easily install Kerdi board, while Durock will require two people at the very least.


Cement board, including Durock is not 100% waterproof. While it can handle some moisture, it can’t handle a lot. Kerdi board is significantly more waterproof than Durock is. However, combining both of these can be an excellent option!


Durock is not only more difficult to cut, but it’s also far more heavy compared to Kerdi board.


If this is a high-foot-traffic area, then Durock may be the best option since it’s stronger.

Kerdi Board vs. Durock: Which Should You Pick?

It will mostly be up to you and what your project entails. Durock and Kerdi boards are both excellent materials and offer their own benefits. So hopefully, this article has helped you out so you’ll now be able to figure out which one you should select!

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