How to Build a Porch Roof

Porches are a great complement to any home. These supplementary living spaces let you relax outdoors while still enjoying the comforts of dry, elevated flooring and easy access to the house. But uncovered porches are less useful than covered porches. Rain and sun limit your time outside, plus porches that receive the brunt of the elements will deteriorate much faster. When you build a porch roof, you extend the porch season and you protect the porch and the side of your house.

Basics of Building a Porch Roof

Porch roof construction can be as simple as building a shingled lean-to that projects off of the side of the house, supported by vertical columns. It's not a complicated task, but heavy building materials are involved and it always helps to have an assistant on the job.

Porch Roof Angle

It is usually best to angle, or pitch, the porch roof. Flat porch roofs are more difficult to waterproof and have a greater possibility of leaking. Porch roofs that pitch downward promote water drainage. For visual appeal, the porch roof's angle ideally should match the angle of the house's roofing.

The minimum roof pitch will be determined by the type of roofing used. The standard 3 tab or architectural laminate shingles require a minimum of 2 to 12 slope. If the roof slope is less than that, an alternate type of roofing will be required.

Attaching the Porch Roof to the House

One of the most critical components of the porch roof is its ledger board. The ledger board takes advantage of the house's strength to support the highest edge of the porch roof. The ledger board supports half of the porch roof's weight. Metal drip flashing installed between the porch roof and the house siding prevents water leakage.

Header Beam and Posts

If the ledger board supports half of the porch roof, the header beam and posts support the other half. Vertical six-by-six support posts spaced every eight feet are securely embedded in concrete footers. The posts hold up a header beam. The header beam runs parallel to but lower than the ledger board.

Shingles

The finishing touch of the porch roof is its shingles. Whenever possible, the porch shingles should match the house's roofing shingles.

Codes and Regulations

In most communities, any accessory structure that attaches to the residence must be permitted. Porch roof plans will need to be reviewed and approved by the local permitting office. In some cases, you may be required to have an architect or engineer develop the plans.