JOIN DIYCHATROOM TODAY!

slakfu · 06-01-2009, 05:43 PM

I'm adding a patio roof off of the back of my house. It will run the length of the house (58'). I'm going to run a beam parallel with the house and span the rafters 10'-12'/24"oc off of the house and rest them on this beam. I'll have 6 posts with 2 - 12' spans, 2 - 9' spans, and a 16' span. All post will be 4x6 Doug. Fir except for the 2 on either side of the 16' span - they'll be 6x6 Doug. Fir. The roofing will be the metal roof and the pitch will be 2/12 with snow load possible in the winter.

Will a 5 1/8 x 9 GluLam beam be sufficient for the 16' span? And are the 4x6 Doug Fir posts sufficient for the load between the 12' spans?. If I went with a 1/12 pitch would I need to beef up the 16' beam?

Thanks is advance.

buletbob · 06-01-2009, 08:00 PM

I personally think that the 16' span is to great for a 9-1/2 glue lamb. it wont snap but it will sag over time with a big snow load. I would go with three 1-3/4" x 9-1/2" LVL's with two 1/4" plates this would be good for a 40 psf live load and 15 psf dead load, 115% Snow. if my memory serves me right.
you will most likely need a permit for this and a set of plans, which will have all this spelled out for you.