The hearth encompasses the area in front of your fireplace or stove. Although the hearth is usually decorative to add to the fireplace, it's also preventative. Fireplaces and wood stoves put out a lot of heat; the hearth consists of nonflammable materials to absorb the heat and protect your flooring and structure. Your fireplace or stove should recommend a specific R-value for the hearth material, or it may simply recommend what products to use to build your hearth to protect wood subfloors and joists. If you're building over a concrete slab, the hearth is strictly for aesthetic purposes and you can simply extend it. Does this Spark an idea?
Find the minimum size acceptable for your hearth. The typical in-front-of-door measurement is 18 inches, but a wood stove requires acceptable distances around the stove on all sides. The bigger the hearth, the safer it is.
Measure and mark out this distance from the front of your fireplace or around your stove. Use a pencil to do the markings on hard floors or a washable marker to mark carpet.
Cut out the flooring where you've marked. Depending on the flooring surface, this may require a saw or utility knife. For hardwood or laminate planks, a pry bar may do the trick without any cutting needed. Do not damage the subfloor.
Clean the exposed subfloor by sweeping it and removing any debris, staples or other items that make the floor uneven. These items can damage tile or other floor materials and result in a defective hearth.
Install the recommended R-value subfloor in the area you are expanding the hearth if you are not installing over a concrete subfloor. Depending on the product, it may be installed using a mastic, nails, screws or another adhesive product. Follow the manufacturer's instructions.
Install your hearth material in the area. Again, this will vary based on the type of product you are installing. Tile and stone are the most common; follow the manufacturer's guidelines for installing the product in the hearth area.
Finish the hearth with wood trim if you are installing against a wood or laminate floor. You can also install the floor directly up against the hearth; trim and molding simply adds another decorative touch and hides the gaps.