Pitch For Under Deck Roof

If you consider it as similar to a roof than according to code.

Pitch for under deck roof.

Thermoset and thermoplastic single ply roofing requires a minimum roof pitch of 1 4 12 or greater. The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run. Many porches use 22 diameter corner and intermediate footings. This is for metal roofs that have a sealant between their lapped seams.

A number of recently introduced under deck ceiling systems use corrugated aluminum or plastic panels designed to catch water that drains through decking and channel it away from the area below. The roof pitch would be described as a 6 12 pitch. Step 2 install a wood support structure for your panels screwing a row of 2 by 4s running parallel to your wall every 2 feet along the underside of your deck. The most common styles are gable hip and shed.

As a result most decks have inadequate footings to support a new porch roof. Porch decks require 25 additional psf for roof loads for a total of 80 psf. That is to say the roof pitch expressed as a ratio tells you how many inches the roof rises for every 12 inches of depth. Lower than the purlin along the house 12 x 1 4 3.

Then stretch a string between them. Consider including an ice and water barrier too. Install the purlin along the house and the outer purlin. The slope or pitch of the under panels can be at any degree that will shed the water.

Sprayed polyurethane foam roofing requires a minimum roof pitch of 1 4 12 or greater. If you choose to add a roof to an existing deck you may need to add additional supports so it can hold the weight of the roof. If the span under your deck is 12 ft for example the purlin at the outer end of the deck should be 3 in. Typical decks are designed to support 55 psf lbs per square foot.

Minimum slope is 1 4 inch vertical in 12 units 2 slope and ideally 1 2 vertical in 12 units 4 slope. Convert the space under a second story deck into a dry spacious patio by installing this simple under deck ceiling and gutter system. First mark all the purlin locations on the deck joists. For a house roof the recommended minimum slope is 2 5 vertical inches for every horizontal foot but a nearly flat roof is fine for under deck installations.

Adding a roof to your deck is best done as the deck is being built. The footings for porch decks must be larger than deck footings. So let s say a roof rises 6 inches for every 12 inches in depth towards the peak. However you can only use this pitch with built up roofing or specialized synthetic roofing.

The primary reason roof pitch exists in the first place is to redirect water.