Garage Structural Help Question (roofing, foundation, sink, building)

[Linda_d]

Hi. My home is about 90 years old (circa 1925), and its detached two-car, story-and-a-half garage is probably between 50 and 70 years old. The ridge line is straight. The left side of the garage roof is straight. The right side of the garage roof dips down noticeably, and there's a significant crack in the cement slab on that side of the garage. My guess is that that dip in the roof is related to the crack in the floor.

Since the garage will be needing a new roof within the next couple of years, I would like to find out what exactly the problem is so that I can decide exactly what's a feasible remedy. I don't want to spend $3-4K on a garage roof on a garage that's not structurally sound but I don't want to sink $20k into fixing an old garage when maybe it would be cheaper to take it down and build new.

What kind of professional would I hire to determine the problem with the garage roof is and explain what needs to be done to repair it? A structural engineer? I want an unbiased opinion based on real knowledge, not somebody trying to sell me a roofing job or just guessing.

Thanks in advance.

[hendersj31]

Sounds like you need a foundation company to take a look at it. If I am reading everything correctly sounds like the slab has sunk on that side

[K'ledgeBldr]

Originally Posted by Linda_d

My guess is that that dip in the roof is related to the crack in the floor.

Probably not. But they're surely related to a soil condition.

A lot of detached garages during that period were built on the ground- no footings or slab. Then later on someone would come along and add concrete for a floor- but the building itself would still be sitting on the ground.

If most of the structure is sound and useable it maybe worthwhile to have it repaired. I don't think a PE would be necessary in this particular scenario. You basically just need a GC that has experience in raising structures and foundations.

The structure would be braced-off in several directions, raised with jacks far enough too build a suitable stem wall foundation (footings/block wall) for the structure to sit on. Lower the structure back down onto the foundation and secure.

[Linda_d]

Originally Posted by K'ledgeBldr

Probably not. But they're surely related to a soil condition.

A lot of detached garages during that period were built on the ground- no footings or slab. Then later on someone would come along and add concrete for a floor- but the building itself would still be sitting on the ground.

If most of the structure is sound and useable it maybe worthwhile to have it repaired. I don't think a PE would be necessary in this particular scenario. You basically just need a GC that has experience in raising structures and foundations.

The structure would be braced-off in several directions, raised with jacks far enough too build a suitable stem wall foundation (footings/block wall) for the structure to sit on. Lower the structure back down onto the foundation and secure.

That's entirely possible since it doesn't look like there's really any kind of sill plate along the perimeter like you would see on your house if not for the sheathing and siding. What's showing on the inside of the garage, which is unfinished, looks like an ordinary 2x4 that's maybe a half-inch higher than the cement.

Thanks.