Total Cost: $300-$800 depending on the type fireplace insert you choose
Decide how big you want your fireplace to be based on the size of your fireplace insert. If you are wanting to build in secret storage on the inside make sure you account for that on the sides of your insert so that you have enough room. I recommend mapping the size out in the space using painters tape to get a visual representation of how big your fireplace will be that you are building. Map it all out on paper and write out your measurements before heading to the store. It will make things a lot easier if you can keep this paper with all the details on hand throughout your project to refer back to.
You are going to start by building the face frame of your fireplace. Start by building the main rectangle piece to the size you would like your fireplace to be. Once this is complete, work inward to build the frame that your electric insert will sit on. I recommend laying your fireplace insert down on the ground so you can visualize where you would like it. I decide to center mine horizontally and vertically. Once you decide the placement, add your support pieces of wood that you will sit your fireplace frame on. Most will come with instructions but are all pretty much the same when it comes to the install. You want to have a support piece of wood that the fireplace will sit on and then two vertical boards that will support the sides. You will use these side supports to secure the front of your fireplace.
Using your 2x2s build the side panels. You can simple create two rectangles that are the same size. I recommend making sure these are square when you build them. I made the mistake of not checking that everything was square and just eyeballing it and it made things a-lot more difficult when I started building in my inside storage cubbies.
Once you have your two side panels built as your face frame, simply attach them together to create the base of your fireplace. Be sure to drill pilot holes before screwing so that you don’t split your wood (I made this mistake the first time and had to rebuild one of the side panels).
After you attach the side panels and the face frame you will want to add some support across the back. I used my 1×6 board and left over 2x4s to create 3 supports that ran horizontally across the back. I would do one near the top, middle and bottom to secure it evenly. You could also use these support beams to secure the fireplace to the studs of your wall if you aren’t wanting it to be mobile.
I decided that I wanted to build in some custom storage into our fireplace. This is totally optional. You can skip this step if you aren’t wanting to add storage. I cut plywood into squares to make my shelving and screwed them in from the outside. Make sure they are level as you work. After my shelves were attached, I cut sheets of underlayment to use for the sides of my cubbies. I secured these with my nail gun and just measured for each one. This took the most amount of time. Looking back, it may be easier to do all of the sides in big rectangles and then add in your divider shelving instead of having to cut each individual square, totally up to you!
After all of my sides and shelving were in and attached, I caulked all of the edges, wood filled any rough spots and then sanded everything smooth once it was dry. The finish work is an easy part to overlook but it truly is what takes the DIY to the next level and makes it look professional. Once everything is painted, you won’t even be able to tell where any of the seams are, etc.
The next step is to attach the doors. I am using the underlayment that I used for the walls of the cubbies to make my doors. You want to use a thin piece of wood here or else the doors will be too thick/heavy when you attach the shiplap. Cut your underlayment piece to the size you want the door to be. Install your piano hinge so that the door opens and shuts to your liking. I installed the piano hinge toward the back of the fireplace so that it would swing open from the front toward the back. Repeat this step on the other side as well.
Once you have all of your doors attached and functioning, it is time to wrap the entire fireplace in shiplap. Start on one of the doors and working top to bottom, attach your shiplap with your nail gun. (make sure you use short enough nails that they don’t pop through the underlayment) We will be attaching a corner piece to the door of the shiplap to cover the edge so just make sure your shiplap is flush with the shiplap on the face fireplace. Continue working around the fireplace until all of your shiplap is installed. Remember, we will be installing a corner piece so your corners where the sides and front meet don’t have to look perfect.
Take your corner piece and attach it to the door so that it over laps the side panel and front face shiplap boards. It works best if you can install it while the door is shut to make sure the placement is correct. I secured mine with a few brad nails and some wood glue to make sure it would stay. This is what makes your doors look hidden when they are closed.
Place your electric fireplace in the space and secure it per the instructions. The fireplace insert I chose doesn’t get hot in the back so there is no danger having my hidden storage. Make sure that the fireplace insert that you choose doesn’t radiate heat from the back.
I built my mantel out of a sheet of 1/4 plywood but you can use whatever you would like. You are going to cut 5 pieces; top/bottom (same size), two side panels (same size) and the front panel. I added two dividers on the inside of mine for additional support but this is totally up to you. Using your brad nailer and wood glue, attach the pieces together so that you have a rectangle (everything attached besides the front panel). If you want to have hidden storage in your mantel you can install the surface mount soft-close hinges which will allow you to open and close the front so you can store your cable boxes, cords, etc. If you don’t care about the storage, you can secure the face piece on with your nail gun.
Paint and stain however you’d like and voila! I used the color grizzle gray by Sherwin Williams and the stain on my mantel is 1 coat of Provincial and then 1 coat of Antique White. Make sure that you use a wood conditioner/pre stain before staining to ensure that it goes on evenly. This will take 5 minutes and you will be SO glad you did it.