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Racking 1 Story House Frame 2

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zero1238

Structural
Oct 6, 2017
68
I completed an inspection this week of a small 1 story, 1,250sf home where the client was complaining about their walls. The home is geometrically shaped like a square with a small addition off of the front and back, and the main bearing wall runs from front to back. In her living room, there was a pull-down staircase that led to habitable attic area with a 7' vaulted ceiling and knee walls built 4' in from both side walls. When I was up in the attic, I realized the ceiling joists were constructed from 2"x4"s, the spacing of which I couldn't confirm due to the finished floor but still scary as they spanned over 11'-6". When I went downstairs, I discovered that each wall running front to back, including the exterior side walls and main bearing wall were all racked and leaning toward one side. The side walls were measured to lean 1" over 48" and the center bearing wall was leaning 1-1/2" over 48". I firmly believe the lack of proper ceiling framing is probably contributing to this but I'm trying to figure out a fix for this woman. If the opposing walls were leaning away from one another, I could see pulling them in with come-alongs but this is a totally different story. Anyone ever come across this before and know of a possible approach toward resolving it. I could strengthen up the perpendicular walls to account for shear but I think we also need to pull these walls in a little more in addition to maybe reframing the ceiling. I think they have have positioned some roof load on the ceiling too by building those knee walls 4' in from the exterior walls...
 
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The worst racking I've seen is usually from ceiling joists going the opposite direction of the roof rafters.

A cosmetic fix is going to be a similar situation to jacking a floor IMO. Is the upside of pushing everything back plumb going to be worth the work/ potential collateral damage that may go along with it?

For the structural repair, strengthening the ceiling framing, adding blocking, and adding a lot of Simpson fasteners are all pretty easy to do.
 
The first step would be to reinforce the joists. Like with 2x8 or so.

Next, is the attic habitable? If not, you can add a turnbuckle at each rafter. It's kind of expensive. I don't like turnbuckles at 4'-0" OC, it concentrates the loads and splinters/splits the joists. Even with a turnbuckle at each joist, you really need to watch the connection and use something small diameter or somehow connected with nails or small screws, which is a bit of detailing you'd need to figure out. This option is not feasible with 2x4, it's assuming you reinforced it.

If the attic is habitable, I'd consider adding collar ties at each joist (usually they're not at each joist, but for 2x4, I'd do it). And strengthen the connections between the rafters and ceiling joists.

As for the existing damage, one option to consider (not exactly code compliant) is to just leave it there. Just minimize future damage. Fixing it might be quite expensive.
 
Exactly, I'm thinking that trying to move it back into place will cause more damage than what the client is ready to take on. The attic is habitable but I'm going to recommend that no one go up there until this situation has been (structurally) resolved. I'll definitely be sistering the ceiling joists and improving the connections with mechanical connectors.
 
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