Pitched Roof Under Deck

Installing a porch roof over an existing deck is usually not recommended unless the deck was originally designed to support a future porch.

Pitched roof under deck.

The project illustrated here was a complete teardown and rebuild so i framed the roof with 2x8s spaced on 16 in. Summer calls for sultry nights under the stars and sun drenched cocktail gatherings making the backyard deck the ultimate destination this season. Instead a pair of beams rest on supports called sill plates to create a frame for the deck. A deck on a sloped roof requires a different approach to the framing underneath the joists.

Once you have your beams in place everything above them joists deck boards balusters and handrails is the same as for any other deck. Whenever i install decking over a roof i make sure the framing is structurally sound and properly pitched to drain water. Install the purlin along the house and the outer purlin. Porch decks require 25 additional psf for roof loads for a total of 80 psf.

Lower than the purlin along the house 12 x 1 4 3. Roof deck framing unlike for decks at ground level doesn t entail a ledger attached to the rim joist of a house. Centers supported by a beam and a ledger as on most decks. Then stretch a string between them.

For those who desire a bit more shade and privacy while soaking up the rays however a deck roof may be in order. If the span under your deck is 12 ft for example the purlin at the outer end of the deck should be 3 in. First mark all the purlin locations on the deck joists.