My fireplace used to look like this:
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I first placed a couple of pieces of our old quartz backsplash (from our DIY kitchen backsplash project) on top of the hearth to get a basic idea of where the mantel had to sit. I’m glad I saved those!
Then I drew out a careful plan with lots of math and measurements of the basic mantel piece. I had to build the form with the raw MDF sides facing out (rather than to the sides) because I knew they would be covered up by trim. Turned out all the corners and sides got covered up so that was moot but at least it allowed me the freedom to make that decision. I also had to subtract inches from the sides to account for the space the trim would take up.
I decided to build the top center piece as high as the boards under the old mantel so I could use that as an anchor to attach the entire mantel to the wall. I don’t know why but the people who built the fireplace wall didn’t have any studs on either side of the tiled portion for me to attach my mantel to.
I started making some rough cuts with my 3/4″ MDF and ended up realizing I had miscalculated a few measurements. This is why it’s good to dry fit stuff! Plus things are not always square and perfect. I used clamps to get a basic idea of what I was doing and get the exact measurements. I ended up changing a couple. I’m not an expert…I was in awe of the carpenters who can just take measurements and then go back to their shop and create the entire thing which fits perfectly.
Once I had the measurements and wood pieces cut to the right size, I used a Kreg Jig to make pocket holes to attach two sides together for each leg piece. Then I glued and nailed the other side in since I didn’t have enough space for pocket holes on the other side (my drill and the pocket hole bit wouldn’t fit. I’m sure there is probably some tool that allows for this but I don’t have it.)
Once I built each leg, I made the center connector piece that is the bridge across the top. I used pocket holes to connect it to each leg but I also reinforced it with an extra piece of MDF nailed in. (Sorry this picture is so sunny)
I put the entire mantel in place and so far, so good! It was a snug fit, which was good. There were a couple of gaps here and there but they would get covered by trim. I also added a top piece which is nailed to the mantel but not nailed to the stud in the wall yet. I can’t attach it to the wall until the quartz it in place, not to mention I wanted to take the entire mantel outside and spray it with paint.
Trimming it out:
I used 1×3, 1×2, and 1x4s on this. On all the front pieces it’s 1x3s. I started the trim by turning some 1x2s on their side and wrapping each leg right where it meets the cross piece. I did the sides first, making them flush with the front and then added the front piece. I used 2″ nails to secure with my Ryobi Airstrike brad nailer. Then I started adding 1×3’s everywhere else on the front.
To wrap each corner, you have to place a 1×3 on the front, leaving it jutting out 3/4″ on the side and place a 1×2 on the adjacent corner, making sure the wood is flush with each other. Clamps helped a lot with this. You will do a 1×2 because with the extra 3/4″ it’s almost the exact size of a 1×3 and makes it all look even. If you want to be precise you can rip a 1×3 down to the right width but I didn’t want to waste wood or time. And I don’t think you can tell.
I ended up trimming everywhere, including the inside and outside of the legs. When I got to the upper portion of the mantel it got a little tricky. The width I had made the crosspiece wasn’t very wide and appeared squatty, especially when I was starting to trim it. I knew I needed to add height. I couldn’t add a ton without rebuilding the entire thing so I decided to add the top trim so it lined up with the top of the mantel. I used 1×4’s here because the top inch of these pieces will be covered by crown moulding. I had to rip out the 1x3s I used previously (but I reused those on the hearth trim) and make 1x3s that were taller. This was a good decision because it balanced out the mantel so much more.
Once those were in place I used scrap wood behind it to give it more stability. Then I wrapped the entire mantel top with a 1×2 piece of scrap MDF I had in order to give the mantel just a bit more height. I wanted the top cross piece to be the same height as the legs are wide.
Once all those pieces were stable and securely in place, it was time for the crown moulding. What. a. pain. We (and here I enlisted my husband’s help) first tried to just cut it free hand without any jigs or guides. Wah-wah-waaaahhh. Didn’t work. Was a nightmare. Ruined the pieces. We got some of the pieces pretty close but I wanted perfection. I also remember reading about the Kreg Crown Pro, which is a jig that helps you cut your crown moulding perfectly every time.
I went back to the store and bought the Crown Pro and more crown moulding and then started working on it. The Crown Pro is like a little shelf that your crown moulding sits on while you cut it. It also comes with a super handy angle finder. First you find the ‘spring angle’ which is the angle the crown moulding sits at when it’s on the wall (or in my case mantel) and most crown moulding comes in three standard spring angles, 38, 45, and 52. Mine was 38. Then underneath the Crown Pro you set the spring angle. This is where I made a stupid mistake and was looking at the numbers backwards. I had it set at 42 and not 38. Once I figured that out it took only a few minutes to cut all my moulding correctly.
You must place the crown moulding upside down (decorative side on top) when you cut it. It has a handy guide to show you which direction to set your miter and which side to cut on. You have inside corners and outside corners. Mine were outside corners so I kept that in mind while cutting. You also have to hold or clamp the moulding tightly while you cut it to make sure it’s not slipping out of place.
Make generous cuts at first, giving yourself room for error and then shave off little pieces here and there until it’s perfect. I did the sides of the mantel first, using a clamp to hold up my long middle piece (my husband was at work at this point and I didn’t want to wait for him.) I got the sides aligned correctly and then bit by bit cut the middle piece until it was perfect. Also I kicked myself many times for not just buying a trim saw blade because yes, I’m still using the bulky construction grade blade it came with.
Once the crown moulding is in place you can use a little sandpaper to sand any slight gaps and then fill it with a tiny bit of caulk or filler. Once it’s painted you won’t even be able to tell!
That is how far I have come on the mantel. I primed the entire thing and now it’s a little more presentable while we wait for the quartz. Once the quartz is installed I will add the final base pieces to cover any gaps between the quartz and the mantel and then take off the entire mantel and spray it with paint. Once it’s installed and nailed in place I can add the final top piece and the whole thing will be done!
Check out the other parts of this makeover!