After updating our fireplace brick (see post below) we decided the mantle needed to be updated as well. This was our process for building a farmhouse fireplace mantle.
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We started by building the support for the mantle. For this we used a 2x4 cut to a length that would fit inside the length of what we wanted the new mantel to be. We also cut support arms to attach to the 2x4. Then we screwed the support beam with arms to the wall.
Next, it's time to build the mantel box. We used 2 8 inch wide by 6 foot long soft wood boards for the top and bottom of the mantel, a 6 in wide by 6 foot long soft wood board for the face of the mantel, and an extra 6 in wide by 6 foot long board to cut for end pieces. Before we started gluing and screwing everything together, we test fit all the pieces of the mantel.
We laid the face of the mantel on the floor. Then, we put the top and bottom boards on top of the face. Once we did that we realized we should add additional supports inside the box to connect the top and bottom boards. So we cut two pieces of 2x4 that would fit inside the box and attach to the top and bottom. Lastly we test fit the side pieces.
After test fitting we started to really assemble the mantel box. We started by screwing the top and bottom boards to the 2x4 connection pieces . Then we used wood glue and finishing nails to add the end pieces. Once that portion of the box was built we put it on the wall and attached it to the support beam. Then finally, we used wood glue and finishing nails to attach the face.
You could also build the mantel box entirely and then put it on the wall. We wanted to test fit ours before finishing it and since it was up there already we just went ahead and attached it. In hindsight, building the box entirely and staining it before attaching it to the wall would be the best method. That way you can let the stain fumes air out in a garage or shed, instead of your living room.
Next, we filled in the gaps on the side pieces with stainable wood filler. Once that was dried we stained the wood. We made a custom mix of three stain colors we had on hand and tested it on spare wood pieces until we got the color we wanted. Then, using an old washcloth we applied the stain according to package directions.
Once the stain has dried you can add decor pieces and enjoy your new fireplace mantel!
