Second Floor wall framing pulling apart

[dankentucky]

Second floor of our garage has framing for two walls. Both sides, the framing is lifting from the floor. Also, at the top of the framing the walls are pulling away from the roof. The garage has a slab foundation with single beam supporting the second floor made of three 2X10s. Thoughts on how to fix? Thanks.

 

[nadogail]

Lag screws to pull things together.

 

[billconner]

I'd pull a string to see if floor joist sagging is causing this, and then, if sag, figure out how to straighten and reinforce it.

 

[Innovate1]

Seems to me the likely cause is the ridge of the roof settling. That puts outward force on the top of the walls and that movement lifts the walls because they are braced to the outside of the top of the first floor. If that's the cause, and I am not positive it is, then you need some ties between the tops of the second floor walls. Yes, it will reduce the headroom, but it may also keep things from falling down (again, if that's what is actually happening).

I'm guessing a bit but thinking the ends may not be sagging because the end walls support the ridge. You could try to see if the roof ridge is lower in the middle. The walls may also be curved, bowing out at the top mostly in the middle and sighting down them will clearly show if that is the case. Some detailed looking at things to determine what is moving is needed. It could be other things like floor sag as someone else suggested.

 

[cgrutt]

Looks like it may have been caused (at least partially) by shrinkage. Has this been like this for a while or does it fluctuate seasonally? Problem with fixing if this hasn't stabilized is you'll need to account for expansion if humidity and/or temperature increases. Do you have a moisture meter? I'd monitor moisture content and see if gaps tighten up. If structure is still square and level may want to shim gaps before drawing them closed with lags etc.

 

[Hank11]

Show us the "single beam supporting the second floor made of three 2X10s", supply dimensions and a wide view of the downstairs.

 

[Fav Onefour]

Hard to help without knowing what is moving.

I'd find the weak point before even thinking about a fix. You could waste a whole lot of time and effort without addressing the problem.
One good thing in the situation is the gable end construction. It is likely that they are not showing the same issue. That should give you fixed points that are relatively unmoved.
String line is cheap. Get a good roll and start checking. Heck, a cheap laser will do the job even better. I use self leveling versions and screw them right to framing so the beam shoots the exact edge of point I'm checking.
Look at the 2nd floor beam and joists for sag. I'd also check the ridge beam for sag and top of walls where they meet the roof. If the walls bow out and ridge beam sags, it's the roof. If floor beam and joists sag, it's the floor.

Bring your findings back to the discussion. Then it's time to talk about fixes for the actual problem.

 

[wssix99]

I'd pull a string to see if floor joist sagging is causing this, and then, if sag, figure out how to straighten and reinforce it.

+1. It looks like the wall studs are attached to the roof rafters and suspended from the roof. As the floor gets loaded with stuff, it is going to deflect and pull away.