The Forestry Forum

We've built a 16x24 cabin out of nearly all recycled materials. And now we're finally nearing it's end...the porch.  It measures 8x24. I initially planned on using 5 cedar logs for porch posts, spaced 6' apart. But because of the placement of the cabin door and porch pillars, I'd like to omit the 2nd post (the one at 6') and put the remaining ones at 12, 18, & 24.  The roof, I anticipated,  was going to be built from 2x4s that are cantilevered on the post beam covered by metal roofing only, no decking .  My question is this, what dimension lumber can withstand the 12' span and weight of 2x4 & metal? Now mind you, this is a no-frills, I really didnt know what I was doing, but tried anyway kind of cabin. No electricity. No water. No amenities. My thoughts were a double beamed 2x6x12 or 4x4x12. Any help and/or  direction is gratefully appreciated.

Top of the page: Extras: Tool Box: Don P's Forum Calculations: Beam and Column Calculations. Without knowing where you are located we won't know what your specific loads are. Hope this helps.

Thank you. I'll check it out. We're in middle Georgia...snow is rare, but the pollen gets deep. Lol

Ive seen worse stand up for a long time in middle TN.  And by worse i mean butt jointed 2x4s and all sorts of toe nailed eye sores.  A sistered 2x6 would be the high end of shack construction out here.  


Wind poses more danger than snow.  Keeping the tin and 2x4s from being lifted off is your primary concern. 

If you were following code, it would take two 2x10 sistered together to span 12'.  That's for a minimum 30 lbs per square foot load and 10 psf dead load.  A beam made of two 2x6 can span 7'-6", according to the IRC.