How to Build a Gable Front Door Awning

Shane Grey

The term gable refers to flat, triangular walls that cap the ends of sloped roofs. One end of a gable door awning attaches to the wall above the door, and the other end projects several feet beyond the entry. As with patio covers, you can build a post-and-beam frame to support the roof covering and add visual interest to your project. The awning roof's frame resembles a miniature gable roof frame; the tops of rafters anchor to a ridge board, and the bottoms of rafters connect to a horizontal plank.

Post-and-Beam Frame

Gables form triangular walls.

Step 1

Lay out the location of the two posts on the ground with a tape measure and marking paint. Stake, level and align the marks with a set of stakes and a string line level. Dig post holes with a shovel, and fill the holes with concrete. Smooth the concrete's surface with a trowel, and allow the concrete to cure.

Step 2

Align the post brackets with the string lines, and mark the locations of the brackets' screw holes on the concrete with a pencil. Use a power drill to install bracket anchors through each bracket screw hole.

Step 3

Set the posts upright in the brackets, and use a power drill to secure the posts to the brackets with post fasteners, such as lag screws. Fasten a beam bracket to the top of each post with the power drill and post fasteners. Set the beam in the brackets, and fasten the beam to the brackets with post fasteners.

Gable Roof Addition

Step 1

Remove siding or cladding from the area above the door with a pry bar. Lay out the location of a horizontal ledger above the door with tape measure, string line level and chalk snap line. Align the bottom edge of the ledger with the top edge of the post-and-beam frame's beam.

Step 2

Mark the desired length of the ledger on a piece of framing lumber with a tape measure and pencil; the length of the ledger equals the length of the beam. Cut the ledger to size with a circular saw. Align the ledger with its lay out marks above the door, and anchor the ledger to the wall with a power drill and lag screws.

Step 3

Fasten a joist hanger to each end of the ledger with a hammer and nails. Mark and cut a joist for each hanger; the joists span from the hangers to the top edge of the beam. Set the joists in the hangers. Align the opposite ends of the joists with the ends of the beams. Fasten the joists to the hangers and the beam with hammer and nails.

Step 4

Mark and cut a ridge board to support the rafters. Select lumber wider than the rafters for the ridge board. The ridge board spans from the wall to the beam. Lay out and cut rafters according to your design; consult a rafter chart for lengths and angles. Lay out the locations of rafters along the ridge beam.

Step 5

Nail the upper end of a rafter to the ridge beam at each mark. If your awning is small, assembling the ridge beam and rafters on the ground is acceptable. If the awning is large, you may have to hoist the ridge board and install rafters in place. Lay out the location of the rafters on the joists.

Step 6

Lift the assembled roof frame onto the joists. Align the rafters' lower notch, called a bird's mouth, with the outer edges of the joists. Butt the frame's innermost rafters against the wall. Anchor the frame to the wall's framing with hammer and nails or a power drill and lag screws. Align the remaining rafters with their layout marks, and fasten them joists with a hammer and nails. Apply roof covering materials, flashing and sealant to the completed awning frame.