DIY Fireplace Mantel (+ a Bold Paint Makeover)

When we bought our house, this fireplace was a focal point in the living room but needed some love. The insert was rusted, old, and the house inspector who looked over the place before we bought it basically said ‘yeah if you don’t want a house fire, don’t use it.’ Because we in fact didn’t want a house fire and we live in the south and we moved in June, we’ve never used it to make a fire. What we did do, though, is build out this rustic DIY fireplace mantel and give it a bold black paint job.

It’s really brought the whole thing into line with our general house color scheme and covered up the odd strip of tile along the front that seems like it was put there just because there was leftover tile from the kitchen countertops. It took almost a full year for the fireplace to get to her current self because, as with most new homeowner DIYs, making your house a home takes time.

Here are the steps we took for our (very long, very slow) fireplace makeover.

Tools & Materials

Note: Remember that your fireplace may have different dimensions than ours, so make sure you measure and adjust all your pieces as needed.

• 1×6 – 1 piece cut at 68.25 inches for the front, 2 cut at 11.25 inches for the sides
• 1×12 – 1 piece cut at 66.5 inches for the top piece
• 1×2 – 1 piece cut at 66.5 inches for the underside,
• 1×3 – 2 pieces as 8.5 inches for the end underside pieces
• Nail gun
• Nails
• Wood stain – we used Varathane Provincial
• Polycrylic
• Sander

(This is assuming you already have everything in our Getting Started with DIY Toolbox)

How We Did It

Here’s a quick rendering of how it’ll look all assembled, because I have the same knack for explaining what I’m thinking as Hodor does.

Basically, you’re going to make a box that sits over your current, skinny fireplace mantel. It’s easiest if you lay this all out upside down, with what will be your top piece (the 1×12) on the floor or wherever you’re working.

Place the side 1×6 pieces on the outside of either end of the long top piece and wood glue, then nail them in place (this is easier with two people so one can hold it all in place unless you’ve got corner clamps.) Lay the long 1×6 piece along the front of the whole thing and nail/glue into place the same way you did the sides.

Now you’re ready for the underside pieces. Start with your 1×2 piece that’ll tuck in behind the front 1×6 piece. Glue/nail it to that front piece so that the skinnier piece of wood is on the inside of the box, making sure that you’re not gluing it on top of that 1×6 piece (you want the final product to have no seams showing on the front.) Do the same thing with the two 1×3 pieces, gluing/nailing them to the shorter 1×6 side pieces between the skinny front pieces and the open back.

By now, you should have a box with one long end open, and you can quickly fill in any seams with wood filler and let it dry to make the final product look more finished.

(Note: We deliberately made the top piece of the box not quite as deep as the mantel so there would be a little sunken strip for our TV cords to sit out of sight.)

Sand & Stain

We sanded down the whole thing, using 120 grit sandpaper. You could use a higher grit (higher grit = smoother finish) but that’s what we had on hand. We did a swipe over the whole thing, making sure our wood-filled areas were nice and flat, and then went over each of the edges to ‘soften’ them a little bit. We used Varathane stain in the color Provincial to stain the whole thing, then a coat of Polycrylic to seal it and make it easier to clean.

Put in Place and Marvel at Your Work

Once the stain and poly is dry, swirl a generous amount of wood glue across the whole top of your original mantel, then slide your new DIY fireplace mantel box over the top into place and weigh it down with whatever you’ve got on hand (weights, vases, books, etc) for a couple of hours while it dries. Alternatively if you want to be able to remove it (or if you’re renting and can’t do anything permanent), screw it into place in a couple spots along the top and it’ll stay put.

Our Bold Paint Job

The fireplace sat for a few months still white and with the weird tile strip but with its phase one pick-me-up of the mantel makeover. It was like she’d gotten her hair done but was still wearing sweats and her perpetually crusty painting shirt. We then had a handyman remove the old rusted insert and cap off the gas line (because even though we love DIY, we know our limits and do not fuck with any major gas, electrical or plumbing), and that was a huge upgrade in itself.

We considered tiling the whole thing but since the brick was uneven, leveling mortar across the whole thing sounded like a truly awful way to spend the day. Then we considered tile stenciling or painting just the tile parts.

But one day I saw a picture of a black fireplace on Pinterest and got it stuck in my head harder than any Charmin commercial I’ve ever seen (which is saying a lot, because damn can those poo-loving bears make a jingle). Alex wasn’t on board so there it sat for another couple of months until one day he randomly brought it up on his own!

We figured if it turned out terribly we could revisit Plan A and tile over it anyway, but luckily we didn’t need to.

I did one coat of the black (SEE PAINT COLOR HERE) but did touchups, ran out of paint and left it splotchy for a shameful SIX WEEKS.

Once I finally got around to the second coat, I also mixed some of it in with this stone paint texture additive to go over the tile part on the front to help it blend in with the brick a little better.

We also used this paintable cord cover to hide our TV and PlayStation cords and it’s one of those things you wouldn’t notice if it was there but you’d definitely notice if it wasn’t.

Now, the fireplace is finally finished and it looks so good. It’s the perfect bold statement in our otherwise very neutral living room.

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