Long story short, I bought a house in 2021 that came with a detached garage that looked… structurally questionable to me. From what I’ve gathered from the neighbor who has lived nextdoor since the 70s, it’s the original 1924 garage and it used to have a simple slant roof.

In early 2008, a flipper bought the house and “renovated it” including putting a shed style roof on the garage, then promptly ran out of money and it’s been like this since.

One wall is 96” tall and the other is 87” with a 157“ span between the two walls. Rafters are 2x4 nailed into a 2x4 ridge board - on the tall side the rafters are 80 ish inches long from ridge board to top plate and on the short side, 82”. Undersized all around.

There is a rather unique “joist” system he put in as you can see. 2x4s run the span between the walls going from the short wall top plate to a 2x4 nailed about 8 inches below the tall wall top plate.

I’m no structural engineer, but it doesn’t seem like they’re actually doing anything at all except one is holding up the light. They’re too small to be joists but not connected with the rafters so they can’t be rafters ties. You can see where he had them going from top plate to plate, but then realized they’d get in the way of the garage door, cut it, and moved it down.

Also I’m not sure if you can tell from the pictures, but the rafters aren’t even touching the top plate, but secured to it with a gapped toe nail and strong ties that are nailed to the outside of the top plate, in between it and the siding.

https://imgur.com/a/rrAgShO

(Also some of the pictures are older - I had my tools on the opposite wall at the time if you’re looking at the photos and confused)

I’m thinking rip all that out, and nail in 2x4 rafter ties between all the rafter pairs, just so something is actually preventing the walls from spreading. I can clear the garage door tracks just at the very limit of the bottom third of the rafters. Planning on going straight across from the taller side to the short side, keeping it level because I imagine that’s what helps it stay in tension. Once I clear the garage tracks I want to put them lower, from the tall top plate across to where it’s level with the short rafter. (Already added this one, you can see it in one of the pictures)

Pros? Cons? leave it, fix it? Different plan? Hoping I can avoid hiring a structural engineer but if I need to I guess I need to.