Measuring Mantel Shelf Fireplace Surround

When building a fireplace mantel, you need to ensure the proper fit for your mantel surround and your fireplace mantel shelf. To build your fireplace mantel/fireplace mantel shelf, use the following guidelines to measure your fireplace. Our fireplace mantel kits are designed to surround your facing material (brick, tile, etc.). You will notice that we allow our fireplace mantels to overlap your facing material in three areas. 1) Mantel Opening Height, 2) Mantel Opening Width, and Mantel Return Depth. In most cases this overlap should be a minimum of 1/2". To build your fireplace mantel, you should start by determining if a standard size mantel surround will work, if not provide us with the B,C and G dimensions from below for a custom size.

Determining the mantel Opening Height "B"
To determine the opening height "B" of any fireplace mantels, measure the height of the fireplace facing material (facing height) and subtract 1/2 inch to allow our fireplace mantels to overlap the facing material. (You can overlap the facing material up to two inches less than the breast "Z" if desired.)

Determining the Fireplace Mantel Width "C" (Facing Width)
To determine the width "C" of the fireplace surround, measure the width of the facing material and subtract 1 inch. This allows the fireplace mantels to overlap the facing material 1/2 inch on each side. (You can overlap the facing material up to one inch less than the width of each mantel leg if needed.)

Determining the mantel surround Return Depth "G"
All fireplaces have a front or face made of non-combustible material such as brick, tile, marble or slate. This facing material may be installed flush with the wall of the fireplace or it may protrude in front of the wall. The distance the facing material sticks out in front of the wall is the Facing Thickness. The return dimension "G" is calculated by adding a minimum of 1/4 inch to the thickness of the facing material protrusion. If you are building the fireplace mantel over 3/4 inch thick marble, you should specify a return depth of at least G=1 inch.