How to Add a Roof Overhang Without Re-Roofing
Adding a roof overhang, whether you are trying to prevent sunlight from hitting a window, keep rain from falling close to your house or add a bit of an outdoor shaded area, doesn't require re-roofing your entire house. You can accomplish this task with a clever selection of shingles for the new overhang and by using the overhang as an architectural statement.
Remove the gutter, if any, and fascia board from the edge of the roof in the area where the overhang will be positioned. Use a hammer and small pry bar to remove this flat piece of wood that caps the end of the roof joists. Try to remove it in one piece to reuse later.
Cut the lumber for the new overhang rafters to the desired length of the overhang plus 2 feet.
Insert the rafter extension into the soffit up against an existing rafter so that it projects out the desired distance. The tail of the extension should be pinched between the top plate of the exterior wall and the bottom of the roof decking.
Push the tail of the rafter extension up so that it is out of plane with the existing rafter. Alternately, you can hold the back corner of the rafter extension down 1 to 2 inches below the existing rafter. Nail the rafter extension in place by nailing framing nails through the extension and into the existing rafter.
Lightly hammer a nail into the outside face of this rafter extension, roughly 2 inches in from the end and 2 inches down from the top of the rafter extension.
Install the rafter extension on the other end of the overhang area in the same manner, including the nail in the outside face.
Tie two string lines to the nail and then stretch them back to the first rafter. One string needs to go from the nail and over the top edge of the rafter extension, while the other goes from the nail and around the end of the rafter extension. When the string reaches the other rafter, pull each string taut and cross the rafter in the same spots before tying it to the nail in the outside face of the rafter.
Install the rest of the rafter extensions in between the two ends. Use the string lines as a guide. The extensions must barely touch both lines, at the top and on the end.
Cut plywood or oriented strand board sheathing to fit over the newly installed extensions. Measure from the edge of the existing sheathing to the edge of the extensions.
Apply roofing underlayment to the new overhang. Push the underlayment up onto the existing roof beneath the existing roofing materials.
Apply the new roofing materials to the overhang. Follow the manufacturers directions for installing the roof covering.
Things You Will Need
- Tape measure
- Pry Bar
- Framing, trim and roofing nails
- Roof sheathing
- Roofing shingles or sheet products
- Before you begin the project check the depth of your rafters by looking in the attic and measuring them. Most rafters will be between 2x6 and 2x10 in size, although you may find a few 2x4 rafters as part of engineered truss systems. Purchase this size lumber to build your overhang. Also check the thickness of your roof sheathing, typically 1/2" but variations occasionally occur.
- To add an architectural pop, consider using a different type of roofing material - either cedar shake or copper/metal roofing.
- To blend new shingles with the existing, select a new shingle that is close to the existing rather than buying new shingles that are the same as the old shingles. This will allow you to better match the color.
- Working on a ladder can be dangerous. Make sure that your ladder is firmly in place on the ground and rests completely against the wall of the house. If any wobble is present reposition the ladder or have a helper hold the bottom of the ladder to prevent it from moving.