Build A Modern Fireplace Mantel, step by step

We mentioned in this year’s holiday decorating post that we hoped to get some sort of fireplace mantel built this month and, well, Santa delivered! ::pats self on back::

Yes, setting a goal to have a place for hanging our kids’ stockings is a little random, but we were glad to have the motivation to check this project off our list sooner rather than later.

If you recall, our fireplace looked like this when we moved in:

Here is a wider shot of that area right after we got here, simply for kicks. Ah, those packing blankets as curtains are #MEMORIES.

So yeah… it feels good to be here:

Sherry did some work to freshen it up over the summer, like scraping and painting the black surrounded and lightening up the interior brick with paint. And in a surprise turn of events that even I did not see coming, she wrapped up things off with some crystal “logs” (since it is a non-functional fireplace, more on that here). So here is where it was the last time we blogged about it:

The view was much improved, but we still yearned for a bit more dimension and a mantel of sorts. And even more fundamentally, something to cover the rough transition from metal edge to drywall. We were excited to tackle this as a Hands-on because it is in fact the third fireplace surround project that we have tackled.

Our first one was nearly 8 years ago in our second house, which involved covering an old brick mantel and adding a marble tile surround (you can see the final result here). Then a couple of years later we built a new mantel for our last house – this time using remnants of a marble countertop to create the surround:

We enjoyed how both of those fireplaces turned out – but going into this third fireplace project, we hoped something more modern for our more modern house (you can see the outside of it here and here). In general, we have been more drawn towards clean lines and a more modern silhouette for most things lately (perhaps it is the casual beach house vibe, or over a decade of leaning towards traditional things that made us want to flex back in the other direction).

So we dug up some modern fireplace inspiration – like this one and this one – and they immediately felt like they’d be a good fit. With the general direction of where we hoped to end up set in motion, we simply had to figure out to execute something similar (our goal was something relatively straightforward and swift versus something that would leave our bedroom feeling like a construction zone for months on end).

The final look was something we simply kinda figured out based on the wood and molding options available at the store. One of my go-to methods of planning a build like this is simply to lay distinct pieces of wood out in distinct combinations on the floor of the hardware store to pin down something that looks good.

In this case I was texting Sherry photos of each option (like the picture) above to make sure we were on the same page. And the good news is that what we ended up with is something you could easily recreate this weekend! And it only cost us about $105!

As you can see in the picture above, the mantel is identical on all three sides and kinda like an upside-down U (at least that is how we kept talking about it amongst ourselves). We debated distinct thicknesses and depths but ultimately landed on it being 9″ wide on all three sides of the U, and 4″ deep along the outside edge (anything deeper would jut into the room a bit more than we’d like).

It is in short constructed by creating a “hidden brace” that is secured to the wall and then trimmed out to create the final look. You can sort of see what I am talking about in the cross-section I mocked up below using some cut pieces.

It is simply some basic 1 x 2″, 1 x 3″, 1 x 4″, 1 x 6″, and 1 x 8″ boards (you can see them labeled above). The only “decorative” piece of trim is a low-cost piece of inside corner molding that you can find at any hardware store. All of the brace pieces can be raw common boards since they will not be seen, but I chose primed boards for everything that would be visible (my store was out of 1×2″ common boards, so that is why you will see me using a primed 1×2).

Honestly, the toughest part of it all was simply the upfront math. You know, making sure we attached the brace in the right spot so our wrapped up mantel was exactly where we hoped it (we hoped a specific amount of drywall and black metal exposed around it). It may be hard to see in some of these photos (especially the straight-on shots) but we intentionally left some drywall and baseboard visible on each outer edge of the fireplace, rather than having the mantel go fully wall-to-wall…er, corner-to-corner.

The result is a pleasant clean looking wall corner that turns (with the baseboard that follows it around the corner) and then terminates into our mantel, which leaves simply a smidge of drywall exposed on each side of the front of the fireplace column. Feels pleasant and dimensional that way, and the real miracle is that we got all of our measurements right so it worked out simply as we hoped.

So here is a swift step-by-step rundown of how it in fact came together.

Step 1. Construct The Base Of Your Brace

After removing the baseboard carefully (since we’d be reinstalling some of it later), we began by constructing the brace. The brace is three pieces of 1×6″ common board that is attached in that upside-down U shape I mentioned earlier.

I attached the top piece to the two sides using pocket holes, but since this will all be hidden in the end, it is not essential that they be pocket holes. In fact, you could simply attach each piece individually to the wall if that is easier. Simply make sure all of your boards are level and square before you screw anything to your wall.

Step 2: Trim Out Your Brace

With the brace firmly attached to our wall in a few places, we trimmed it out with 1×2″ boards along the inside and outside edges. This will assist your mantel project away from the wall a bit, which creates that dimension we were looking for. Again, 4″ was the depth we chose, but if you want yours deeper simply use thicker wood for this step.

These border pieces of wood will be fully hidden, so it is not essential that they be fairly looking. In other words, you do not need fancy mitered corners and you can cobble together scrap pieces for this part. They do not have to be primed (again, that is simply what my store had in stock that day). Oh and we used some wood glue along with our nail gun to attach them to the wood brace so they are extra sturdy.

These two steps complete the hidden part of the mantel, so now we are moving on to the visible parts of the build.

Step 3: Add Your Face Panels

Even though these next parts are visible, the steps are fairly similar to what we simply did. We began using careful mitered cuts so we got those crisp wrapped up corners and pleasant angled joints wherever two boards met. First up, we brought in two 1×8″ primed boards on each side of the brace:

Again, we used wood glue and nails to attach all of our pieces together. Those are consistently a strong combo for a long lasting hold, since nails alone can cause cracking or loosening over time. That is not my cleanest wood gluing below, but it did the trick!

Next, we carefully measured and cut the top piece to go across and join the two vertical boards to make that striking (let us say it together) upside-down U.

Now, as you can see in that cross-section graphic, our 1×8″ was a little wider than the brace underneath (see how it overhangs on that left side below?). It is not a problem, I simply point it out because you want to make sure you account for it in your math and make sure you are consistent with which side it overhangs (we chose the inside edge). None of the brace is seen, so it is truly simply something to account for so you know where to shoot your nails, and so you end up with a centered result.

Step 4: Trim Out The Edges To Your Liking

With the flat face panels secured, we trimmed out the sides again (kinda like we had done with the brace piece). We chose a 1×4″ around the outside edge to add extra depth and, again, we used mitered cuts so we did not have any raw wood on our edges or corners.

Here it is with the outside 1×4″s brought in…

Then we went around the inside edge with a slightly smaller 1×3″ primed board. The 1×3″ board hung over the edge of the face panel simply sufficient to create a pleasant border.

Since the 1×4″ on the outside edge stuck out even more, we brought in a quite plain inside corner molding to give this outer edge a little bit more detail. We were hesitant to add too much or too ornate molding here because we did not want our modern mantel to skew too traditional, so we felt like this was simply sufficient.

Step 5: Finish Off The Bottom Edge

Going into this fireplace project, we were not sure how we hoped to deal with the bottom side of our fireplace (aka, the open end of our U). Sometimes you simply wait for something to be built and then try a bunch of distinct trim options to see what you like. So after holding up a few scrap pieces, we ultimately chose to reattach the baseboard that had been there before (simply cutting it to fit between the new surround, obviously).

Since it was going against metal, not drywall or wood, we attached it using some caulk as a light-duty adhesive because we did not have any actual adhesive around. And speaking of caulk…

Step 6: Spackle, Caulk, and Paint!

The last thing to do is to spackle your nail holes, caulk your seams, and then paint everything. We used the same paint we have on all of our interior trim, which is Sherwin-Williams Pure White in a semi-gloss finish.

Like I mentioned, we kept our fireplace depth fairly slim because we did not want it to stick out quite far from the wall, but you could easily get the same wrapped up look on the front and use deeper trim pieces to get a deeper profile.

Meanwhile, our version means that our fireside chairs (and our Christmas tree) do not have to bump out into the rest of the room any further.

Sidenote: perhaps Sherry and I should issue a retraction about hating bedrooms with sitting areas, because we put these chairs here while doing a kitchen project and ended up sitting in them all the time, so they live here now. It must have something to do with our bedroom being on the main level, so we go into that room WAY more throughout the day (in our last house we’d come downstairs for the day and our bedroom was simply sort of a place we retired to at the quite end of the night).

Heck, Sherry has taken about a dozen Zoom calls for work from these chairs! Yes, that is right, she has graduated from Zoom calls in bed! (Now that we have a headboard, it is more obvious that it is a bed – but more on the new headboard in a second).

And although this project was driven by Christmas stockings (we truly are plain creatures, are not we?) we hoped to snap a photo of what it’ll look like the other 11 months of the year for our House Tour page. So we slid the Christmas tree out of frame and popped off the stockings for this swift photo. We still plan to build in the cabinets on either side of the fireplace, so picture them with baseboard running under them instead of that dark gap from being up on legs.

But as much as we are looking forward to that clean plain look in 2021 – right now we are enjoying the coziness of this festive-ized holiday version. Oh and if you are wondering how we hung the stockings, we are using our go-to white cup hook solution.

Simply like we did in our last house, we screwed two small cup hooks into the underside of the mantle. Come January we will simply remove the hooks (we store them right inside the stocking themselves in a little ziplock bag) and the compact holes are not noticeable at all. Sherry’s going to share a video demonstration of how that all works on InstaStories for you soon.

Oh and we made one change inside of the fireplace, even though we were resistant to the idea at first! We at last gave it a try, and it makes it especially straightforward for us to get that fireplace glow without bending over. And it ensures that zero stockings will be catching on fire anytime soon (consistently a plus).

In fact, you can see that change in action in the swift video below that Sherry filmed (here are the exact ones that we used). Plus there is a sneak peek at the quite end of our bedroom patio with the fence all painted & our s’mores pit surrounded by chairs:

Note: You can also view the video here on YouTube.

On a somewhat related note, while we are talking about updates in our bedroom: we at last got a headboard! After months of waffling about what we hoped, we chose to stop letting ideal be the enemy of good and we picked up this… wait for it… kid’s headboard for our room.

You know we are suckers for a creamy linen headboard and we had zeroed in on something with a french seam (Sherry taught me this term – I kept calling it a knife-edge), since it feels a bit more casual & relaxed than our last headboard’s extra tailored edges. It simply so happens that Target sells a kid’s Pillowfort headboard in a Queen size – and they call the color “talc” – which is the exact same color of our last house’s headboard. Are we creatures of habit or what? Note: They’ve since discontinued that headboard, but we have linked a similar replacement.

It took a few weeks to arrive, but once it did it was especially straightforward to install and we have enjoying not leaning against the wall anymore while Netflixin’ at night. We likely need to hang that mirror a little higher, but I have been busy building a fireplace, okay? Kidding. Simply been lazy.

Here is a wider shot of the whole wall. Plenty of neutrals, a large pink pillow that Sherry loves, and of course the obligatory salt lamp (that I have on a smart plug, along with our nightstands because nothing gives me a thrill like asking Alexa to turn off the bedroom while simultaneously pointing a remote at the fireplace like a true technology wizard).

To read the first post about this bedroom coming together from July, here are all those details. And here is how we brought in some much-needed storage to either side of the fireplace (still have to fully build them in). If you missed our holiday decorating post with more shots of the tree & various other bottle brush trees everywhere, here is that photography extravaganza.

We also brought in a video walk-through and some additional photos to last week’s post about our kitchen/sitting area, so those are there for your viewing pleasure as well. Oh and we updated our current house tour page too – as well as our Before & After page. And as mentioned, stay tuned for that video on InstaStories of Sherry detailing our stockings/cup hook method. It promises to be RIVETING.

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