How to Put Concrete Over a Brick Fireplace for a Modern Style

Before starting, you’ll want to clear the area of rugs, furniture, and other decor to avoid getting everything covered in dust and debris. You’ll also want a clear working area with plenty of room to spread out your building materials. When mixing your concrete, be sure to do it outside or on a covered surface so that it doesn’t get stuck and harden on your floor.

If your fireplace sports faux-stone, or some other kind of material covering the brick, then you’re going to start the DIY process by chiseling this existing stone away.

For this, you’ll want the demolition hammer and your safety glasses ready to go. Carefully chisel away any pre-existing stone that covers your current fireplace, revealing the brick beneath it.

After you’ve gotten your fireplace to the place where it’s just brick, it’s time to cut the right dimensions for your fireplace. Use a straightedge to measure the correct dimensions that you’ll then use to cut the right-sized cement boards.

To cut the board, throw on your safety glasses and use a utility knife. This way, you’ll have perfectly sized pieces to install before making the fireplace the center of attention in your living room.

With your pre-cut cement boards in sight, you can now start applying the pieces to the brick fireplace. To do so, you can apply a strong construction adhesive to the back of the board. Then you’ll press this onto the brick fireplace. 

If you want a more professional option, you can also apply furring strips as a wooden frame to your brick. However, this is a step better left to the professionals since you’d have to drill holes into the brick before framing a wall to then screw in the cement boards, which is dangerous without an expert.

Once the cement boards are secured, you’ll want to move forward with taping every seam. While this might sound tedious, it’s a really important step. All you’ll do is place appropriately sized pieces of mesh tape over all of the seams, and voila! You’re ready to mix the concrete.

Next up, you’re ready to start mixing your concrete skim coat. Using your mixing tool, follow the manufacturer's instructions to pour the concrete skim coat into a bucket with the directed amount of water.

Finally, the time has to come to apply the concrete skim coat. To do so, take your concrete trowel and put a generous portion of the concrete onto it. From here, you’ll apply the mixture to the cement boards smoothing as you apply. 

(If you’re just adding concrete to the hearth, you’ll directly apply this mixture to your hearth, smoothing every step of the way. Just make sure you have the rest of the fireplace taped off to prevent concrete from getting on it.)

It’s a good idea to start at the tallest point of the fireplace, then work your way down, re-smoothing with every re-application. Once you have the entire fireplace coated and smooth, you’ll wait for the concrete to dry before sanding and repeating the application process. As a general rule of thumb, you can add up to five coats of concrete skim coat until the fireplace is your desired look.

Once the concrete work is finished, seal your concrete fireplace to lengthen its life span and enhance durability. Sealant types include acrylic and epoxy polyurethanes, and they will keep your new concrete fireplace or hearth protected from wear and tear. 

After choosing a sealant, you’ll apply your coats to the renovated area with a paintbrush.

While this step is totally optional, adding a mantel is a fun way to add a bit more style to your fireplace. Choose from traditional white crown molding, rustic barn wood, or a modern black mantel.