How To Build a Mantel

The mantel tutorial I’ve been promising is finally here! Ya’ll know I don’t do too much wood working on this blog, and the real story is that Jesse built this mantel, while I watched and learned, and then I did what I do best: I painted it. However, I learned so much while watching helping Jesse, that it totally made me want to build stuff. That’s the thing about stuff that scares you…once you try it, you realize it isn’t that scary after all. So, this is the story of how Jesse built the mantel. And how I soaked up every minute like an eager, unskilled sponge. Even Geppetto had to start somewhere, people. When, I first started this beast of a project, I knew it would never be complete without a mantel. You may remember that I was dealing with this little naked gem of a 1970’s fireplace. I looked everywhere, thinking surely I could just find a cheap yet beautiful mantel. That = pipe dream. And then I looked online for mantel tutorials, and there weren’t very many of those either. I was so frustrated. So, I convinced Jesse it would be fun to build one. I don’t think he believed me one bit, and would’ve much rather spent his Sunday fishing or golfing, but I think he enjoyed it nonetheless. Plus, not a day has passed since it was built that he hasn’t stopped to pet the mantel for a moment. It cost us a fraction of the price of those fancy mantels (we only had to buy a few pieces of wood which cost us about $20-$30 total), and the entire project only took a few hours to complete. We used basic tools and supplies to build this mantle, most of which we already had from previous projects. Here is a complete list of what you’ll need. Supplies: 1. 4 Pieces of Wood: We used soft pine because it was really affordable. Start with 3 pieces of equal length wood (pre-cut is easiest!) for the front, back, and bottom of your mantle. The front and back should be the exact same dimensions, and the bottom should only be as wide/thick as you want the mantle to appear deep. Get a larger piece of wood (height & width) for the mantle top so that it extends beyond the mantle box on the sides and front. You’ll also need 1 short piece the same height as the front & back so that you can cut it to cap the end on both sides of the mantle. 2. 1 Piece of Decorative Trim: We found a 4″ piece of decorative trim (moulding) with several curves that we thought would look nice attached underneath the mantle top to provide some extra detail. 3. Jig Saw: We used a jigsaw to cut our pine boards, which worked just fine. A table saw would be even easier and provide the most precise cuts. You could also use a handsaw, but (Jesse says) get ready to sweat. 4. Mitre box: We used a mitre box to cut angles to connect the decorative trim on the front and sides of the mantle. 5. Wood Screws: We used wood screws to screw the pieces of pine together. 6. Bolts: We used bolts to do a free floating mount on the fireplace wall. 7. Drill: We used a drill to drill holes in the back of the finished mantle for free floating mount and into the surface where we wanted to hang the mantle. 8. Dremel: You’ll need a dremel (or other precision rotary cutting tool) to cut the end off of bolts. 9. Liquid Nails: We used Liquid Nails to secure the mount and glue the decorative trim to the mantle front and side. 10. Caulk: I used caulk to fill in any gaps between the wood pieces before painting. 11. Primer & Paint: You’ll need primer to make sure your paint adheres. I painted my mantel with semi gloss paint (more details at end of post). Once we had the necessary supplies, here’s how we built it. We found it cheapest/easiest to use these pine risers and some leftover scrap wood. This pine is great because it’s cheap and looks great when painted. However, with pine, make sure to pre-drill the holes that you intend on screwing because it will often crack or break if you try to nail it or screw it in directly. We learned this the hard way. And that’s when my trusty wood filler came in handy. Assemble your wooden mantle starting with the front and back (identical pieces) to the top & bottom. Screw the pieces together. Remember, you’re basically making a big hollow wood box. You just offset it a little so that the top extends beyond the front board…this basically just makes it look like a mantel. Here’s a closeup side view to show you how far we offset the front piece. You are essentially creating a little ledge. Next, you’ll attach the 2 sides and the bottom to finish the box. In the below picture, you can see that the mantle is now sitting upright. We used scrap wood from an old wooden shelf for the sides and bottom, so if you don’t have any old wood around, you can buy an extra pine board. Also, since Jesse built me a mantel, we will just smile understandingly at the fact that he used my next dresser project as a table to saw stuff on in the spider garage. 🙂 Anyways, here’s a side shot of the mantle. Attach the bottom, and measure and cut your end pieces to close in the mantle. By now it should really be starting to look like a mantel. The next part is adding some decorating trim below the ledge and on the sides to really fancy it up. We just bought one big piece of decorative trim and used a mitre box to cut the necessary angles. Back when we did this project, we bought this mitre box kit (affiliate link) with clamps and a saw for $12. It’s pretty basic, but totally gets the job done when cutting angles. You’ll need to measure your trim an inch longer than you think, because cutting it at a 45 degree angle will bring it back in an inch so that it can perfectly meet the side pieces, which you will need to cut the same way. Treat the trim like a puzzle. Line it up in your head and piece them together a few times to make sure you cut the angles the correct direction. You may want to practice using your mitre box on some junk trim first..not because it’s hard to use, but because if you are doing it for the first time, it might take a couple practice runs to figure out your angles. So, you’ll need one long piece for the front (that will be glued below the ledge) and two short pieces, one for each side. Here is a side view to show you how the angles will line up. You will be glueing the trim up underneath the ledge. To glue the trim onto the mantle, I used Liquid Nails (affiliate link). Once the mantle is completely assembled, there will be tons of tiny gaps between your wood. If you are painting it white, you’ll want to caulk all of the gaps to make it look seamless. I used DAP paintable acrylic latex caulk (affiliate link). Both can be seen below. You can also fill any seams or gaps in the corners of your decorative trim with wood filler. Our cuts with the mitre box weren’t perfect, so I just filled the gaps with this wood filler and sanded it to match the grooves of the trim. Once painted, you’ll never know. Oh, and definitely don’t skip the caulk…it makes a huge difference in how professional it looks. The below pic is after I had used wood filler and caulk to make the entire thing seamless. To hang the mantle, Jesse used a free floating mantle mount technique (found here) that you can make yourself with a few bolts and some liquid nails. In a nutshell, you just drill holes into the surface where you’re mounting the mantle, screw in heavy duty bolts, cut the heads off the bolts and cover them in liquid nails, and then slide on the mantle. You will need to pre-drill holes in the mantle spaced and aligned to the bolts coming from the surface where the mantle is to be mounted. Side note: Ignore the other 85 holes we drilled when we mounted our tv on the mantle. It worked great, but I ended up not liking it. Oops. Sorry rocks. I hung the mantle before I painted it because Jesse was about to go out of town for the weekend, and this girl needed her mantel hung. You will probably want to paint your mantel before you hang it. 🙂 But, regardless of where you paint it, here’s how I painted my mantle. It’s similar to the method I used on all of our trim and most of the furniture I painted. It’s a really simple process. I primed the wood using Zinsser primer (affiliate link) and then painted it with Behr Ultra White in a semi-gloss finish. I used a paintbrush to apply the paint and a small foam roller to smooth the brushstrokes. And that, my friends, is how we made our mantel! Thanks so much for stopping by today. I’m so so glad you’re here! For related posts, you can check out the following: How I stacked a bazillion logs. 2 years of horrible decorating decisions. It happens. A scary old post that gives you a decent tour of the upstairs. And the updated version of that tour. ‘Til next time!! Follow my blog with Follow my blog on or or Subscribe to LiveLoveDIY with email! Enter your email address: –>