Building Our Fireplace: The DIY Mantel – Our DIY House

This post may contain affiliate links ยท This blog generates income via ads

One of my most favourite features in Our DIY House is our fireplace. It’s THISCLOSE to being done – I’m waiting on the cleaning fairy to sprinkle me with motivational fairy dust so that I can clean the slate surround and seal it. We’ve already had our first fire in it and it was glorious. I’ll share the final picture of it soon (this will be my official motivator to get it done), but meanwhile I’ll share with you the process of building our DIY “rustic glam” fireplace.

At first, I wasn’t sure about this whole “wood burning fireplace” thing. It was my hubby’s choice to splurge a little a lot on one, and I wasn’t convince that it was the right choice. Well, I am now! It adds such a beautiful feature to our home as you walk in the front door. It’s warm, cozy and inviting.

Building Our DIY Fireplace: The Mantel - The DIY Mommy

Hubby’s more of a rustic guy and I consider myself somewhat of a glamourous girl (on the inside, anyhow), so we each added a little of our own taste to the fireplace design. I wanted a thick, white mantel and he wanted rustic slate surround. I wasn’t sure about the combo at the beginning, but I’m totally in love with the contrast now. My inspiration was this gorgeous fireplace in this Sarah Richardson designed living room. I liked the sort of coastal feel it had.

If I’ve never said how wonderfully talented my mom is, I’ll say it now: my mom is talented. She saw my vision and she told me right away that her and Dad could make my vision into a reality with less than $70 worth of wood & MDF (no joke!) and a TON of their hard work.

Building Our DIY Fireplace: The Mantel - The DIY Mommy

First, we mounted a piece of MDF (about 1″ thick by 12″ high) onto our fireplace (that was wrapped in cement board) for the back of the mantel. We checked into the requirements of how far away from the firebox our mantel had to be and used that as a guide for placement. We wrapped this piece around the sides as well.

Building Our DIY Fireplace: The Mantel - The DIY Mommy

Next we screwed on a piece of 1 x 3″ lumber to the front top edge.

Building Our DIY Fireplace: The Mantel - The DIY Mommy

We screwed on another piece of 1 x 3″ to that and mounted a slim piece of 1 x 4″ beneath it as pictured above.

For the actual mantel piece, my parents laminated two thin pieces of MDF together to make a thick piece, and then they notched out the shape of the fireplace so that the mantel would wrap around it. This was screwed to the top of the wood pieces.

My parents made the beautiful little corbels by laminating 4 pieces of thin MDF together and cutting out the shape with a jigsaw. They were sanded to perfection, primed with Killz and painted so that the seams are totally invisible!

A thin strip of MDF was mounted to the bottom of the main piece. We made sure it was wide enough to jut out from the slate we were installing around the mantel.

Building Our DIY Fireplace: The Mantel - The DIY Mommy

Here, you can see the crown molding we added to the front (from the mantel piece to the piece on top of the corbels) and a cross-section of the pieces we used to create the mantel.

Building Our DIY Fireplace: The Mantel - The DIY Mommy

The entire thing was then primed with Killz, and painted with 4 coats of white semi-gloss paint (Valspar Ultra White).

Building Our DIY Fireplace: The Mantel - The DIY Mommy

The result is one of the most substantial and gorgeous looking mantels I’ve laid eyes upon in real life. Can you believe it cost less that $70 to make (but many, many hours of work)?

Building Our DIY Fireplace: The Mantel - The DIY Mommy

Later, I’ll share with your our rustic glam fireplace reveal and how we installed our pretty slate tile to complete our look.

Thanks Mom, Dad & Hubby for all of your hard work on this gorgeous, heirloom mantel! ย ย 


  1. Christina, your fireplace is gorgeous! I have a question about the fireplace itself. My daughter is going to use a lighter colored, but similar split-face stone on their fireplace. Did you have your firebox set forward some, or was the ‘bump out’ dimension created by adding the layer of cement board alone? Thank you!

    1. Thank you, Sheryl! We actually ended up having to frame out the fireplace to accommodate some plumbing on the sides of it. It wasn’t originally our plan, but I’m really happy with the look! It’s just bumped out the width of a 2 x 4.

  2. Hi there,

    Love the fireplace mantle! What is the thickness of the actual mantle shelf? It looks like 1″ or 1 1/2″?

  3. Hi there, I appreciate your instructions on how to build a fireplace mantel! It turned out gorgeous btw.
    I have one question, in regard to the paragraph, “For the actual mantel piece, my parents laminated to thin pieces of MDF together to make a thick piece…”, is it supposed to read, “…my parents laminated *two thin pieces of MDF”? I was trying to figure out what the thin pieces of MDF were laminated TO or WHAT? :):)

  4. Beautiful mantle! I will use it as a guide for my own mantle project.

    FYI the two pieces of 1×3 that you describe in your post are probably 2×3 from what I can see in the photos.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.