Roof Ledger Board Size

Typical rafter spacing codes will specify a minimum spacing of 16 inches 19 2 inches or 24 inches.

Roof ledger board size.

This tells you the size of the beam needed to support the porch s roof. You want a flashing that won t react with. House rim joist must be minimum of 2x sawn lumber or 1 in. The closer the rafters are to each other the stronger the roof will be.

Douglas fir lvl no attachment is allowed to strand lumber syp lvl the mudsill i joists floor trusses or other materials. This means the example porch would need a 6 inch by 8 inch beam. Typically you will need to install your bolts alternating high and low 2 from the top and bottom of the ledger board. In the example d calculates to 7 75.

X 9 in. It is always better to have a large rafter rather than be concerned with a sagging roof. It should be 6 8 inches above grade ideally but you can get ground contact pt that can be placed closer. Calculate the initial value for d then round it up to the nearest inch.

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. If your local building authority has a rafter spacing code you may not space rafters wider than required by code. 2x6 p treated bolted as the size of your deck. 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.

As a rule of thumb bolts can be spaced 16 on center for supporting joist span up to 12 in length. Lag screws may be spaced at 16.