First, you'll need to score the top and sides of the mantel that touch the wall. The goal is simply to cut through the caulk that was used to finish off the mantle. That is helping secure it to the wall.

More than likely, your mantel is only attached with a few nails/screws and a little glue. If there's extra trim on the inside part around the fireplace, remove it first so you can re-use it later, if you wish. Then, since this is the demo stage, simply use a crow bar and pry that bad boy off.

Move from one side to the other, to slowly ease it off. If necessary, score it a little more as you work.

Our mantel had trim on it that we didn't love, {Ionic columns circa the early 90’s} so we removed it with a wood chisel and mallet. Then we sanded off all the glue with a belt sander and an orbit sander for a smooth, workable surface.

Next we measured to where we wanted to add on to our mantle on both sides. We wanted our mantle to have a depth of 6 1/2 inches and a width of 8 1/2 inches for a nice, chunky look. Our current mantle had a 3 inch depth, and a 4 inch width.

The height of our mantle was 53 inches.

To build the two boxes that would cover the legs, we cut a 1 x 4 x 8 down to 53 inches and cut (4) 7 inch pieces (I used a compound saw).

We also ripped a 1 x 10 x 6 down to 8 1/2 using a table saw and cut it to 53 inches with our miter saw.

We ripped a 1 x 8 x 8 down to 6 1/2 inches and cut it at 53 inches.

I then used some wood glue and our finish nailer and 2-inch nails to build the box overlay.

To build the box, first attach all the 7 inch pieces as cross bars to your 4 inch and 6 1/2 inch piece. Then lay your 8 1/2 inch piece on top and attach it with glue and nails.

Repeat the above process for the other side as well. Once both sides are built, go ahead and attach them to the existing mantle using wood glue and your finish nailer.

Now you'll need to measure your center piece and build it. Again this is the same process as building the sides: A simple box with a couple of cross supports. After you build it, attach it to the existing mantle using wood glue and your finish nailer.

You're ready to attach the mantle back to the wall. For this, first make sure your wall is cleaned and sanded. (As well as your mantel too.) Then, secure the mantle to the wall using at least (4) #10 3 inch wood screws. We put (2) in the bottom inside of our mantle and screwed them into the rat seal or the 2 x 4 sitting behind the wall on the floor. The other two we screwed in on the inside top, because we knew there was a stud there. The key is to make sure you are attaching to a stud, not dry wall.

To really give the mantle that finished clean look, we decided to add some simple trim. We took a few 1 x 2 x 6's and ripped them straight down the middle using a table saw, cut them to length, then simply glued and nailed them to the mantle.

Next, we simply caulked around the outside of the mantle, and anywhere there was a nail hole. (Make sure to use a paintable caulk.) Once everything was dry, we painted the mantle.

And it really is that simple to upgrade your mantel.