Slab and foundation crack, how serious it is?

[mmzymxf]

We are buying a town house interior. The inspector found cracks on both sides of the crawl space block walls that line up with the crack in the garage floor. He said this was an indication of the front part of the home having some structural settling. See my illustration. How serious is the problem? The home is about 30 years, and these cracks don't look new. Thanks!

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[Jim Katen]

We are buying a town house interior. The inspector found cracks on both sides of the crawl space block walls that line up with the crack in the garage floor. He said this was an indication of the front part of the home having some structural settling. See my illustration. How serious is the problem? The home is about 30 years, and these cracks don't look new. Thanks!

Click to Enlarge

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The cracks could also indicate where the building pad switched from native soil to fill. If the cracks aren't particularly wide, they might be unimportant. It's hard to tell without observing them for several months.

[Eric B]

Since you did not say how large the cracks were I'll assume they're not very wide. Being that it is a 30 year old structure I'd be inclined to say that there was some initial settlement after construction that is no longer occurring. On the other hand, some areas of the country are experiencing unprecedented rains which has caused movement of soil that had been previously stable.

[JohnC]

What was your inspectors opinion on the cause and concern about the cracks? Inspectors usually find cracks and most are typical but some are major concerns.

He should give you his opinion in this regard.That's what he's paid for.

John Callan

We are buying a town house interior. The inspector found cracks on both sides of the crawl space block walls that line up with the crack in the garage floor. He said this was an indication of the front part of the home having some structural settling. See my illustration. How serious is the problem? The home is about 30 years, and these cracks don't look new. Thanks!

Click to Enlarge

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[John Dirks Jr]

What about differential movement at the cracks?

A hairline crack with the surface on each side flush and level usually indicates less potential for problems.

Rotational difference is another thing to look for. That is when the gap created by the crack is wider at one end than another. A thin crack with a consistant gap is usually less of a concern than a crack with a gap that is wider at one end and narrower at the other.

[Darren]

All masonry cracks; my concern would be settlement. Is there settlement at the garage floor? (you can look at the garage walls and see where the concrete was poured against the wall). Is there any type of movement is the block wall?

Your location says Madison; if this townhouse is located in Northern NJ and you do not feel comfortable about the cracks, you may want to call Jim Guider PE @ 973-428-1101.