Maximum span without intermediate support question
Hi all, first post here as I couldn't find the info anywhere else. Basically, I'm building a patio cover that will be tied into my existing house roof. The cover will be just under 15 feet long. I will be using light gauge corrugated metal sheathing, so the roof cover itself will be very lightweight. My question is this: Can I use 2X6's for rafters without any middle support(to prevent sag), or will I have to go with 2X8's. The roof will slope around 4 inches over the course of the entire span. Any help is greatly appreciated!!
Your geographic location would be helpful due to snow load etc. Regardless, 15 foot span with 2x6 is a big NO. I believe 12' is maximum for even 2x8 16" oc here. Your local bldg dept would be able to tell you what minimum width and spacing would be for 15'.
You are planning on putting corrugated panels on basically a flat roof which also is not very wise planning. May want to think through your design a little more before you commence construction.