Roof Ledger Board Size

House rim joist must be minimum of 2x sawn lumber or 1 in.

Roof ledger board size.

Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. As a rule of thumb bolts can be spaced 16 on center for supporting joist span up to 12 in length. Typically you will need to install your bolts alternating high and low 2 from the top and bottom of the ledger board.

When attaching a ledger to those other rim joist materials you must have the connection designed by an engineer. This tells you the size of the beam needed to support the porch s roof. Typical rafter spacing codes will specify a minimum spacing of 16 inches 19 2 inches or 24 inches. It should be 6 8 inches above grade ideally but you can get ground contact pt that can be placed closer.

If your local building authority has a rafter spacing code you may not space rafters wider than required by code. Ledger the same size as the rafters and fastened to the studs with x5 lag screws spaced page 2 of 6 at 32 maximum on center for up to a 10 0 rafter span. It is always better to have a large rafter rather than be concerned with a sagging roof. Our roof rafter calculator tools are handy for calculating the number of rafters needed rafter length calculator lineal feet of rafter board feed in ridge and sub facia and the total board feet in the roof.

2x6 p treated bolted as the size of your deck. X 9 in. In the example d calculates to 7 75. The closer the rafters are to each other the stronger the roof will be.

You want a flashing that won t react with. Douglas fir lvl no attachment is allowed to strand lumber syp lvl the mudsill i joists floor trusses or other materials.