How Far Apart Do You Put Boards For Porch Roof

In this example the section of roof is 20 feet wide and 14 feet from the fascia to the peak.

How far apart do you put boards for porch roof.

While your beam size ultimately depends on design factors such as whether you include a covered roof structure or open lattice strips a familiarity with conventional beam spans gives you an idea of how far apart you can space your posts. This translates to seven rows of strips 20 feet long spaced two feet apart or 140 lineal feet of. Too high a snow load means the purlins fail regardless of how close together you put them because a 2 4 or 2 6 flat can only span a certain distance between trusses as snow loads increase. The smallest beams for patio covers are typically 4 by 6.

The other issue is the building code. The best size board to use is 1x4 pieces that are 10 feet long. If not the patio roof only bears it s own weight and the block stiffens the joists dramatically. The higher the snow load the closer the purlin spacing required.

That s a long span. Do you get a massive amount of snow. Just a saw kerf will do though i prefer a smoother less stress concentrating broad dish shaped router cut but with a 1 8 or so cut into the wood that additionally reduces the wood strength and screw holding power of nominal 1 think 3 4 actual wood. However you will want to have boards that can be used as braces for the tresses.

The ridge cut also called the plumb cut at the top of the rafter the birdsmouth cut which itself comprises 2 different cuts where the rafter meets the building s wall and the tail cut at the base. The common 4 on center design is suitable for snow loads up to 60 for most applications. Another thing you will need to do is brace the second gable end on the roof and secure it. If so you may want to go to 2 x 8.

When you cut the rafters you ll need to make 3 separate cuts.