Steps to Putting a Roof on a Porch

Installing Supports

• A porch roof relies on sturdy supports and becomes dangerous if the supporting structures aren't capable of holding its weight. The walls of a screened-in porch offer the right support, says Hometime, but freestanding posts and columns also work. Any freestanding supports should be anchored in poured concrete footers in the ground. Simply nailing a post to the top of the porch won't work. Walls should be attached to the house framing through exterior wall studs for stability.

Framing

• Even a basic sloping shed-style roof requires trusses to support the plywood and roofing materials of your porch roof. Prefabricated roof trusses save time and effort for homeowners who want to build a gable or hip-style roof according to Hometime. Set the truss that is anchored on the house's exterior wall first, and then install the ridge board that the rafters attach to. Once all of the trusses are installed, the rafters are nailed into place and the framing of the porch roof is complete.

Roofing

• Plywood and roofing felt form the sheathing of the porch roof, but what materials cover them is largely your choice. Use the same material that the rest of the house is roofed with to keep the porch roof from looking like a late addition. If the porch roof does not have have a sufficient angle, you'll have to use asphalt shingles according to Front Porch Ideas and More. Porch roofs must rise in height at least 4 inches over each 12 inches of their horizontal length to work with other materials, like shake shingles or clay tile.

Ceiling Finishing

• Once the porch roof is properly supported, framed and covered with roofing materials, it is technically complete. However, adding some kind of decorative finish to the ceiling of the porch makes it more visually appealing. Painting the plywood with exterior paint is a quick finish. Installing paneling like beadboard or tongue and groove boards takes more time but creates an outdoor space more like an interior room. Homeowners have the choice of installing these finishing touches months or years after building the porch.