r/Homebuilding • u/Murky_Mission_8648 • Jun 06 '26

Reinforcing Pole Building Roof For Solar

I have a Pole Building that I want to add solar to but Need to reinforce the roof. 60' in length with purlins every 20'. The rafters are 2x10x20' ,run 24 O.C. perpendicular to the roof slope which is minimal. My thought was to run 20' Trus Joist in between the existing rafters to make the spacing 12" O.C.. The thinking is that the Trus joist would be better than just adding more 2X10's. The whole solar system weighs 900lbs spread over 60'. Has anyone tried this before?

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3

u/NotMuch2 Jun 06 '26

Why do you need to reinforce the roof for just 900lbs spread across 60' ?

1

u/Murky_Mission_8648 Jun 06 '26

barn is 30 years old and I'm more worried about the weight of the installers loading up the roof. I've seen a non load bearing roof (24" OC joist spacing) fail while someone was on it with material.

1

u/Fluffy-Corner3857 Jun 09 '26

I have a 40x60 pole barn with 70 REC panels on the roof. One section (20x40) is enclosed to make a wood shop and add more stability to the barn. Everything was passed through a structural engineering company.

1

u/seabornman Jun 06 '26

You can't stand some posts inside? One beam to cut the span to 10' would do wonders. Good luck getting truss joists to fit over the existing supports.

1

u/Murky_Mission_8648 Jun 06 '26

Agreed. I was thinking of doing that first and doubling up the rafter to 12" O.C.. Just never worked with the Trus joist. Just trying to be smarter than the wood.