Warning: ignoring advice on joist spans almost cost me a roof collapse

My uncle, who’s been framing houses for 30 years, told me to use 2x12s on 12-inch centers for a 20-foot span in my shed build last summer. I thought he was being old-school and overbuilding, so I went with 2x10s on 16 inches to save cash. After 3 months, the roof started sagging 2 inches in the middle, and I had to tear everything out. The lumber yard guy confirmed I was way under spec for a live load of 40 pounds per square foot. Has anyone else learned the hard way that those span tables are not just suggestions?

2 comments

2 Comments

blair_dixon9d ago

You figure the lumber yard guys ever get tired of seeing people come in with the same "I should have listened" look? At least now you've got the strongest shed on the block.

danieljenkins9d ago

Nah, the lumber yard guys probably love it. They get to watch the same show every weekend, chuckle behind the counter, and then sell you twice as much lumber as you needed because you're so embarrassed you'll buy anything. It's a win win for them. Plus, your overbuilt shed is now a local landmark, all the neighbors use it as a reference point for directions. "Turn left at the fortress, you can't miss it.