How to Build a Free-Standing Fireplace Mantel

What You'll Need
Measuring tape
Lumber (measured accordingly)
3-inch wood screws
Wood glue
Construction adhesive
Wood paint/stain
Table saw
Miter saw (optional)
Wood putty

If you live in a region with prolonged cold weathers, an indoor fireplace is a must. However not all houses come with a built-in fireplace and therefore learning how to construct a freestanding mantel can be useful. Remember to keep in mind the size and look of your room before constructing a mantel so that it does not look out of place.


Step 1:  Deciding the Dimensions

Draw the mantel you wish to construct on a piece of paper. Measure the height and width of your fireplace; add at least 8 inches to these measurements to determine the inner dimensions of your mantel. A typical inner width is 34 inches and height 38 inches, external height 46 inches and width 48 inches. Shelf dimension is usually 52 by 2 inches. Using a chalk and a perfectly straight stencil, start drawing outlines on the wall. Draw lines for the mantel’s inner and outer dimensions, above and on both sides of the fireplace. Draw a box for the shelf. Extend the two lines that you drew for the inner heights up to the bottom of the shelf. You should now see two rectangular pillars on either side of the fireplace going up to the bottom of the shelf, the shelf itself as well as another rectangle joining the two pillars, right under the shelf - the base. Dimensions are 34 by 8 inches.

Step 2:  Preparing the Wood

Cut the wood with a table saw according to the wall’s measurements. In case of cornices, use a miter saw to trim the angles. Since you are making 3d pillars, you will need four pieces of wood for each. The wood facing you and the wall will be cut according to the outline size. However the side faces will be of the same length but a smaller width. Determine this width but subtracting a few inches from the width of the shelf so that the shelf can rest on them but also protrude a little. Cut one slab for the base and one for the shelf. If you want a thicker shelf you can have two to stack, one on top of the other. Prepare the wood by first sanding it using medium-grit sandpaper. You can either paint the wood or use a natural wood stain to enhance the wood’s beauty.

Step 3: Constructing & Installing the Freestanding Mantel

Lay out a leg on the floor and construct the pillar like a hollow box with the smaller width legs facing each other and an identical leg on top. Do this process using wood glue. Also use nails for better support. Add the base in the middle of the two pillars. Finally let the structure stand and attach the shelf on top using wood glue. Make sure it only exceeds the pillar’s width from one side. Using wood putty, hide all the holes that the nails made in the wood. Purchase a mounting board for optimum results and attach it to the wall using construction adhesive. Using wood glue and 3-inch wood screws, attach the freestanding mantel onto the mounting board and hence the wall.