Problem With Garage.\

[downslope]

There is a 4-car garage on my property approx 40 ft X 20 ft. The front entrance side has 4 sliding doors. It sits on a concrete block footing and has a poured concrete floor.

I believe the building was moved to its current location about 70 years ago and was formerly a horse stable. It is sheathed on the inside, so you don't see the exposed studs. You can see marks on the sheathing where the stall partitions used to meet the back wall. There is tongue and groove sheathing and cedar shakes on the exterior. It seems to be structurally sound except for what appears to be one big problem.
The back wall has 4 double hung windows in it. There was always be a slight bulge in the rear wall where the end garage bay is; I assumed someone had bumped it parking a car inside at one point.

What is happening now is that the sill plate is starting to move off of the footing. The wall is moving out, but only at the bottom. There is one 10 foot stretch near the original bulge where the sill is completely off of the foundation about a half inch. Nothing has collapsed yet and I have blocked it up till I decide what action to take. The sill plate looks like a rough cut 2x4; it doesn't appear to be rotted or termited. The wall is firmly anchored at the corners, nothing is moving there (yet!).

I had two contractor friends look at it and they said obviously it has to be fixed (soon) but they really don't know why it's happening. One older guy did tell me that back in the 1940's they probably didn't anchor anything, just plopped the building down on the foundation. He contends it had to have started when someone bumped it from the inside years ago. I think it may have gotten a little worse after tropical storm Sandy in October.

So, why is this happening and how to correct? Two of my friends, a building contractor and excavating contractor think we can lift the sill a little with the tips of a forklift and then push it back with jacks and 4x4's or 6x6's laid on the pallet fork tines, then work form the inside to try and anchor better.

Another contractor friend who is more conservative suggested temporarily reinforcing the whole outside wall with a lattice of 2x6's, where the vertical ones would be over studs , then jacking from the outside and pulling with cables or chains attached to eyebolts thru the open front bays.

If we decide to push or pull it back in place should I remove some bottom sheathing on the inside and make some "relief" cuts in the 2x4 sill so it has room to go back into place without stessing the corners?

Any ideas/suggestions would be appreciated.

 

[MIKE R]

I think the first option is probably your best bet. Its hard to tell what to do without seeing it. Once you get it back in place get some concrete ancors from the hardware store put them every say roughly every 10 feet That would hold it from moving.

 

[texasjohn]

You and the contractors you've talked with are there and see the problem and likely will see the best solution.

I'm not a construction person...but what came to my mind was getting a number of hydraulic vehicle jacks and timbers placed against the roof timbers, lifting vertically with the hydraulics to take pressure off the wall, then pulling the wall back in place (or perhaps pushing it. Perhaps some sort of shim between the foundation and the sill plate. This approach leaves the forklift free to move to where additional forces are needed in case you don't have enough hydraulic jacks.

Good luck!

 

[dave1949]

Any chance a window or roof is leaking, allowing moisture to get into the bulged area? If the wall is taking on moisture, it might expand, that's the only idea I have why it would begin moving.

I would try to put it back in place very gently. It seems to have "taken a set" with the bow and doesn't want to go back into place, then I would do as you thought, cut kerfs, or maybe cut the wall entirely, get it lined up, bolted down, and then tie the wall back together.

 

[BeezFun]

I wouldn't do anything until you understand what is causing the progressive movement. Can you post pictures? I'd do the Columbo thing and wander around with a 6' level and see if any parts of the building are moving out of plumb, like maybe the building is racking. Stretch a line along that sill and see if it's really deflected as much as you think- is it possible the footing was never poured straight or that the footing is moving instead of the sill? Freeze thaw cycles can be hard on block foundations if they don't have rebar or wire in them. If I understand what you're saying, that sill is 4-1/2" out of straight and it's 20' long. That's a very large deflection, put a level on that back wall and see if it's really that far out of plumb. Sometimes it's hard to tell what's moving. Are the tops of the side walls bowed out, like maybe the rafter ties aren't holding, or don't exist. That might transfer some kind of force to the end wall although I can't imagine how without seeing the construction details.

 

[BHD]

not that the picture is that good, but I posted so you had an Idea what I was talking about,
the sheds on this barn had major problems (my dad had hogs and he let them root down under the stem wall on the building, on the south side the door was open and a strong wind, and literal lifted the shed up and off the foundation. I think I used a handy man jack to lift it back up and on the foundation that was tilted out and sagging down, and then blocked it to level, then I went in side and put a beam (a few 2x4 or 2x6) so I had some place to push and took a post and cut it to length, put a hydraulic jack and lifted it letting the wall hang, then I took pulled out the old foundation about 10 foot of it, dug down and poured a footer, (it did not have a footer before) and then formed up a stem wall, and when cured let it back down (put bolts in the new wall, and then keep doing that in about 10 foot sections until I got to where there was no damage, about 40 feet of the 60 foot of stem wall, and had to some on the north wall as well,

but you can most likely place some beam on the under side of the rafters and take the weight off the wall, and then swing it back in place, and then if needed one may be able to fill the cores of the blocks in that area so one can put a bolt into the core area of the blocks,
now if you start to lift and wall is not going up STOP, before you push the rafters off the wall, but one can do a jack ever 8 to ten feet, If concerned put some metal ties on the rafters to the walls before you start to lift,

 

[downslope]

I wouldn't do anything until you understand what is causing the progressive movement. Can you post pictures? I'd do the Columbo thing and wander around with a 6' level and see if any parts of the building are moving out of plumb, like maybe the building is racking. Stretch a line along that sill and see if it's really deflected as much as you think- is it possible the footing was never poured straight or that the footing is moving instead of the sill? Freeze thaw cycles can be hard on block foundations if they don't have rebar or wire in them. If I understand what you're saying, that sill is 4-1/2" out of straight and it's 20' long. That's a very large deflection, put a level on that back wall and see if it's really that far out of plumb. Sometimes it's hard to tell what's moving. Are the tops of the side walls bowed out, like maybe the rafter ties aren't holding, or don't exist. That might transfer some kind of force to the end wall although I can't imagine how without seeing the construction details.

I'l try some of the things you say, but I doubt very much that the foundation is compromised. Only the bottom of the wall is bowed out, not the top. The bulge is quite obvious, and yes, in the worst spot I would say it has bowed 4.5" A lot of the bow is only about 1" or less off the blocks. You have to figure too that the sill probably consists of several pieces but the whole wall is strengthened by all the sheathing inside and out; that may be what's given it stiffness and prevented total failure up till now.

The reason I posted on here is just to get some opinions, since the guys I've had look at don't always agree on what is going on. My neighbor is bringing another retired builder type to look at it tomorrow, so maybe I'll have a plan in place by the weekend. And of course the building is filled to the gills with "stuff", old vehcle, tractor, and a lot of stuff piled along the rear wall (but not leaning against it) looks like a lot of things to move out of the way, throw some out, etc.

 

[sld]

If it were me, I would remove the sheathing on the inside of the bulging wall. Sounds like a lot of work but that is the best way I can think of to really see what is going on. If you see no anchors you shouldn't even have to lift it to push / pull it back to square.

Plus, it should be easier to persuade the wall back to straight without the decking.

 

[BeezFun]

And of course the building is filled to the gills with "stuff", old vehcle, tractor, and a lot of stuff piled along the rear wall (but not leaning against it) looks like a lot of things to move out of the way, throw some out, etc.

If this building is a gable style, that rear wall is not load bearing so that helps your work. If it's got a hip in the back and there's rafters bearing on that wall, I'd be especially careful to understand what's going on before I tried to move it. Normally there would be no force in that direction, so I can understand why it moves if a car runs into it, but I can't think of any scenario that causes it to keep moving.

 

[KennyG]

I think the easy part is anchoring the wall. I would put some lumber on the walls or rafter ties if you have them and jack up a little to take the weight off and then anchor it back to the foundation in the proper place. What I would worry about is the connections between the walls and the rafters. If they have loosened up, the building may be likely to keel over in a high wind. If you have some convenient locations to add some diagonal bracing back down to the walls, it would probably add some margin of safety.