How to Build Return Eaves on Roofs

Return Eaves

• A typical home’s roofing structure consists of rafters or trusses. Both rafters and trusses provide support for roof sheathing materials, such as shingles and for sheathing underlayment materials, such as plywood. Rafters appear as wood pieces that extend downward from a roof’s peak. Trusses consist of multiple pieces of wood joined together in a web-like framework. This framework provides additional strength and support for the roof frame. Both rafter and truss structures extend out past the outer wall of the house, though not far enough to create eaves or overhangs. Building return eaves means extending rafter or truss ends to the point where water flows away from the home’s walls and foundation structures.

Remove Framing

• The semi-overhang created by roof rafters or trusses includes a framing structure that connects the rafter ends to the walls of the house. The frame consists of a wood piece known as fascia, which acts as an end-piece that runs across the ends of the rafters. The fascia connects to a wood plank-like piece that braces against the wall of the house. When building return eaves, remove the fascia and the wood-plank brace. The roof rafters also rest atop of wall plates. Wall plates sit between the wall of a house and the actual roof rafter. With two people working, removing the battens makes it possible for the second person to secure rafter extender pieces from the attic interior while the first person works on the outside.

Add Extenders

• Adding rafter extender pieces requires figuring out how large a piece of wood will fit between the roof sheathing and the wall plate piece. The dimensions of this piece will determine the size of the rafter pieces needed to create return eaves. The length of the overhang will vary depending on how steep a slope the roof has. Lower-sloped roofs will require longer overhangs, while shorter overhangs will work with steep-sloped roofs. When cutting the rafter extension pieces, cut them at three times the length of the overhang, since two-third’s of each piece will sit underneath the roof sheathing as bracing. Nail extender pieces onto the rafter boards at 6 to 8 inch intervals. The person attaching the extender pieces will have to do so from inside the attic interior.

Rafter Blocks

• Rafter block extender pieces provide an alternative option for steep-sloped roofs where shorter return eave structures will suffice. Because the slope of the roof determines how easily water will flow off, eave lengths don’t need to extend out too far. Rafter blocks consist of individual block pieces that extend up to 8 inches from the existing rafter lengths. Rafter blocks attach to a ledger board that runs across the ends of the rafter pieces. So, instead of nailing individual extender pieces for each rafter, return eaves are constructed as one-piece blocks along the length of the roof. Once extender pieces or blocks are in place, replace the fascia and plank framing to fit the new extender portions.