Is cement board ok for a fireplace?

Author: Ashlynn Dickens  |  Last update: Wednesday, May 6, 2026

The benefits of using PermaBASE Cement Board on fireplace insert surrounds include: Durability: Comes with a lifetime limited warranty for residential interior applications. Design flexibility: Ideal substrate for direct-applied veneers. Time savings: Lightweight and easy to cut for speedy installation.

Is cement board safe for a fireplace?

This means you are not required to build an entire fireplace out of brick or cement and instead use non-combustible materials for framing, wall construction, and finishing. Typically, fireplaces require steel framing and cement/concrete board when building within the unit's clearance to combustibles.

Can you line a fireplace with cement board?

A: Yes, HardieBacker board can be used as a fireplace facing. HardieBacker 1/4'' board can be used as a component in a 1-hour fire resistive construction when installed in compliance with National Evaluation Report NER-405. HardieBacker boards are recognized as non-combustible, when tested according to ASTM E 136.

Is cement board fire resistant?

The primary mechanism through which cement board achieves its fire resistance is its non-combustible nature. The cement within the board has a high thermal mass, meaning it can absorb and store significant amounts of heat.

Is cement board better than drywall for fireplace?

The cement board is more ideal to use rather than drywall, as it is way stronger and has a porous surface ideal for the masonry adhesive to really stick.

Why I installed cement board on my WHOLE chimney breast instead of plasterboard!

What are the disadvantages of cement board?

It is not as resistant to fire and cannot be used on floors or where water could come in contact with it because it is weak when wet. Because it can deteriorate over time, regular inspections of its condition should be conducted, especially when high-traffic areas are involved.

How thick is cement board for fireplace?

The H5 fireplace requires a 1/2” (13mm) thick non- combustible cement board or equivalent, to be used as a wall surface immediately above the unit—see diagram for minimum coverage. Extending the cement board well beyond the minimum shown will help avoid cracking due to differential expansion of materials.

How much heat can cement board take?

A high density cement board reinforced with inorganic fibers, NAD-11 is suitable for applications requiring continuous operation in temperatures up to 500°C (932°F). NAD-11 is dimensionally stabile, non-combustible, chemically inert, and it retains its mechanical strength at temperature.

What board to use around a fireplace?

Fire-resistant boards are perfect both as a construction and insulation material and fireboards with pattern can be used as a decorative cover for fireplaces and stoves. They also can act as wall lining, or insulation core in industrial range.

Is HardieBacker 500 cement board fireproof?

HardieBacker® cement board has been evaluated by the BBA and approved with certificate no. 04/4100. The products meet the European standard for fibre cement - EN 12467 and its reaction to fire, in accordance with EN 13501-1, is A1,S1-d0. The product is therefore classified as fully non-combustible.

What is the best material to line a fireplace with?

If you are going to line the inside of a fireplace (rather than render or just paint) then you'll be using some kind of fireproof lining-board.

Does it matter which side of cement board you use?

The smooth side is ideal for mastic applications, as it increases adhesive coverage. The textured side is ideal for mortar applications, as it enhances bonding and reduces tile slip. That said, mastic or thin-set mortar can be used on either side of the board without compromising performance.

Can you use Durock around a fireplace?

Standards: DUROCK Cement Board is listed by Underwriters Laboratories, Inc., for use with UL-listed solid-fuel room heaters and fire- place stoves.

Can cement be used in a fireplace?

Our heatproof fire cements and plasters can be used for a range of heat resistant applications such as around fireplaces, BBQ's, pizza ovens and in some furnaces.

Is Hardie cement board combustible?

But Hardie® siding will not ignite when exposed to a direct flame, nor will it contribute fuel to a fire. Because James Hardie brand products are non-combustible, many insurance companies offer a discount. We recommend sharing fiber-cement siding's fire-resistance qualities with your insurance carrier.

Does it matter which side of the Hardie board faces out?

Install smooth side up. Install HardieBacker boards perpendicular to subfloor panels. Never allow all four corners of boards to meet at one point.

Is cement board OK for fireplace?

The benefits of using PermaBASE Cement Board on fireplace insert surrounds include: Durability: Comes with a lifetime limited warranty for residential interior applications. Design flexibility: Ideal substrate for direct-applied veneers. Time savings: Lightweight and easy to cut for speedy installation.

Can I use cement board as a heat shield?

The industry's solution for heat shields

PermaBASE cement boards are the industry-preferred choice. Installation-ready and easy-to-use, PermaBASE® cement boards eliminate the need for field fabrication, saving time while allowing for enhanced performance and wood-burning stove placement closer to the wall.

Is cement board considered non-combustible?

Fire Resistance. DUROCK Next Gen Cement Board is a non-combustible panel and meets CAN/ULC S114 and ASTM E136.

What temperature is too hot for cement?

Fewer concrete problems indeed exist during the summer, but excessively hot temperatures can cause problems as well. If you intend to install concrete in temperatures around 90 degrees, you'll need to adjust the mix and installation process to accommodate the heat.

Does it hurt cement board to get wet?

In general, cement boards are a highly moisture-resistant building material that can withstand the damp conditions found in bathrooms and showers, where water can accumulate and seep into the walls over time.

Does heat transfer through cement board?

Cement board typically has a thermal conductivity (k-value) ranging from 0.18 to 0.35 Watts per metre-Kelvin (W/mK). Compared to concrete (1.0-1.8 W/mK), this relatively low thermal conductivity allows cement boards to provide some insulation value.

Is Durock the same as cement board?

Durock, HardieBacker, and Wonderboard are three popular cement-based backer board companies.

How to board a fireplace?

Here's how:
  1. Measure the height and width of your fireplace opening.
  2. Cut a piece of ½-inch plywood to these dimensions.
  3. On the back of the plywood, use self-adhesive insulation to cover one side of the plywood.
  4. Decorate the front-facing side of your plywood with paint or create a textured effect with fabric.

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