How to Build a Modern DIY Concrete Fireplace Face for Your Gas Fireplace

Before and after DIY concrete fireplace makeover showcasing dramatic transformation.
Since moving into our home seven years ago, I’ve never been completely satisfied with the fireplace. The stone cladding didn’t match my style, and the off-centered gas fireplace always bothered me. I dreamed of a modern, concrete look that would fit our family room’s aesthetic. While relocating the fireplace wasn’t feasible within our budget, I finally decided to take the plunge with a DIY concrete fireplace makeover. I’m thrilled to say the results exceeded my expectations! This project not only transformed the fireplace but also cost less than $200—much less than I anticipated for such a dramatic change.
If you are a visual person you can find the Youtube video linked below
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Materials

Supplies

Tools

Tools & Materials Needed to Move Outlet and Light Switch

Materials Needed to Patch Up the Wall

Before photo of a stone fireplace with a white mantle, ready for a DIY concrete makeover in a modern family room.

Planning and Design

Challenges with the Design

Since moving the gas fireplace to the center of the wall wasn’t an option, I had to come up with a plan to make it appear balanced. I chose to extend the fireplace face. However, in deciding to do this, I faced another issue: centering the fireplace face on the wall meant that the light switch and outlet to the left of the fireplace would be in the way.
Fireplace wall under construction with a light switch and outlet highlighted on the left side. The image shows a partially finished fireplace with stacked stone and surrounding construction materials.
I considered extending the outlet and light switch to the fireplace face, but after creating a 3D model, I realized that wouldn’t look good.
3D PICURE SKETCH WITH LIGHT SWITCH & OULET ON FIREPLACE
After debating back and forth, I decided to move them both to the adjacent wall. I mean, how hard could that be???
If you are doing this, don’t be like me and forget to take a detailed picture of how the wires were connected. It took us over five hours to figure out what we did wrong…
Living room under renovation with a mounted TV above a partially demolished fireplace. Wooden framing and construction tools are visible around the fireplace, and two holes mark the removed light switch and outlet on the wall.

Revamping the Nook

I also wanted to update the nook next to the fireplace. I am no longer into the farmhouse wood panel look, so I wanted to update to a clean look with built-in storage to help hide the clutter and make it more visually appealing.
I used Live Home 3D to create a 3D model of the fireplace area to visualize my design. I will share the details of how I built this in an upcoming blog post and detailed video.
3D rendering using live home 3D app of a modern fireplace with a stone surround, wooden mantel, and built-in shelving with vertical wood slats, black shelves, and cabinets. Decorative plants and baskets accent the design.

Planning

Once I finalized the design, I planned how to build the fireplace face frame, as well as the cabinet and shelf for the nook, and made my list of materials.

To keep the fireplace from protruding too much, I decided on an extension of about 3.75 inches, equivalent to the width of a 2×4 plus a 1/4-inch backer board.

Here’s a 3D rendering of my plan using SketchUp:

![PICTURE OF 3D PHOTO FROM SKETCHUP] frame
Since we already had an existing hearth, I extended it along the wall as well. This required cutting into the existing flooring, an important step to ensure a seamless finish and to provide our LVP floors with the necessary expansion gap to prevent buckling.
PICTURE POINTING TO HEARTH

Step by Step Instructions to DIY your Own Concrete Gas Fireplace

Step 1: Remove the mantle

Depending on how your mantel is mounted, the removal process might differ from mine. My mantel was secured with nails. If there’s caulk around your mantel, be sure to cut it with a utility knife before attempting removal.
Woman removing a white fireplace mantle from a stone fireplace during a DIY home renovation project. A TV is mounted above the fireplace, and a ladder and tools are visible in the background.
After cutting the caulk with a utility knife, I used a pry bar and hammer to remove the mantel.

Step 2: Demolish the Stone Fireplace Face

The easiest way to remove stone from your fireplace is by using a demolition hammer, which you can rent. However, we chose not to go the easy route to stay within our budget. It wasn’t extremely difficult, but it definitely required some effort!
Partially demolished stone fireplace with broken stones and debris on the floor, exposing cement and brick backing.
We used a chisel and sledgehammer. If renting a demolition hammer fits your budget, definitely rent one! It took us about an hour to demo and clean the fireplace face. We used a pry bar to remove the cement from the drywall. The drywall was damaged since the stones were installed with cement directly on it, with a steel mesh in between.
In-progress DIY concrete fireplace makeover with stone removed and tools ready for the concrete application.

Step 3: Cut Into the Existing Flooring

Since this is a permanent fixture, I made sure to cut my LVP flooring, leaving an expansion gap to prevent damage. I used my circular saw with a track and carefully adjusted the blade depth to avoid cutting through the subfloor.
For more details on how to install LVP floors, check out my blog post, How to Install LVP Flooring for Beginners. I didn’t install these LVP floors, but I did install the ones on my top floor.
cutting into lvp floor with circular saw and a saw track
Because there’s a layer of glued flooring under our LVP, we had to scrape it off with a scraper.
Cutting into the floors was terrifying, but I’m so glad we did it!
PHOTO OF FLOORS CUT

Step 4: Build the Fireplace Face Frame & Hearth Frame

I used 2x4s to build both the fireplace face frame and the hearth frame, connecting the pieces using pocket holes. I attached the frame to the wall by screwing it into the studs.
Wooden 2x4 frame around a fireplace under construction, with a mounted TV and hardwood floors.
I strategically positioned the vertical 2x4s so that the horizontal ones would align with the wall studs. Below, you can see close-up pictures of the frame.
Close-up of wooden framing for a built-in project, showing pocket screws and metal brackets for added support.

Step 5: Cut and Attach Cement Board to Wood Frame

Cut the cement boards to the appropriate size using a circular saw or an angle grinder with a carbide or diamond blade, we used an angle grinder with this blade. I aligned most of the cuts so the edge of the cement board matched up with a vertical 2×4 attached to the wall.
Man cutting cement board with an angle grinder while wearing goggles and a dust mask.
Use a drill and cement board screws to attach the cement boards to the 2×4 frame.
Partially completed fireplace renovation with cement backer board installation, tools on the floor, and a TV mounted above the fireplace.
Partially completed fireplace renovation with cement backer board installation, tools on the floor, and a TV mounted above the fireplace.
important neon green transparent graphic Leave a gap between each piece of cement board to prevent cracking.
 
For the corners, overlap the pieces slightly while still leaving a gap (see picture below).
important neon green transparent graphicWhen placing the cement boards on the floor, do not place them directly on the floor. I used some of my son’s cards, stacking three to leave a small gap for the LVP flooring’s expansion space.
For the corners, I used drywall corner bead to make the corners look smooth, as I will show you in the next step.

Step 6: Tape the Cement Board Seams

Once the cement boards are attached with the screws, tape all seams between the cement boards using fiberglass mesh tape.
Close-up of a fireplace structure with cement boards and joint tape.

Step 7 Apply Thin-Set Mortar

Mix the thin-set mortar according to the directions.
Apply a thin layer over the tape using a putty knife.
For the corners, use corner beads cut to size and secure them with the thin-set mortar. I cut the corner beads with metal shears. I tried using scissors instead of metal shears but it made it more difficult to get a clean cut.
I let it dry for about 24 hours, once it’s completely dry, I sand down any rough raised spots if necessary.
Close-up of a cement board with partially applied thinset mortar and blue painter’s tape along the top edge during a DIY fireplace project.
PICTURE OF RAISED SPOTS

Step 8: Apply the Concrete Finish

Using a drywall mud pan, mix small amounts of concrete with water. Gradually add water until the mixture has the consistency of thin pancake batter. It’s important to mix in small batches, as this dries quickly.
Apply the mixture to the cement board with a large putty knife, using long, even strokes with minimal pressure, then increase the pressure at the end to feather it out.
After one coat, the seams in the cement board may still be visible, but they should disappear after the third coat.
Below you can see what it looked like while the first coat was still drying
diy concrete fireplace first coat of cement on cement board wet
What t it looked like after the first coat dried below.
concrete Fireplace with the first coat of cement applied, drying in a DIY home renovation project. A TV is mounted above, and tools and supplies are scattered around the room.
We applied three coats, lightly sanding with a 220-grit sanding sponge between each coat except for the final one.
concrete Fireplace with the third coat of cement applied, drying in a DIY home renovation project. A TV is mounted above, and tools and supplies are scattered around the room.
I am so happy with how it turned out, and I’m so glad I finally tackled it. But now it feels like we need a bigger TV lol… We haven’t sealed the concrete yet, but I plan to find a matte concrete sealer soon to complete the look.
DIY concrete fireplace
If you’ve been postponing your fireplace transformation, I hope this guide inspires you to take action! The process was easier and more affordable than I anticipated, and I couldn’t be happier with the outcome.

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