Should You Be Worried
About One Small Crack?

Question: I am in the market to purchase a new home. I recently signed a contract with a builder and have paid $4,850 in earnest money toward the purchase. During my walkthrough of the home I discovered a crack in the slab. This crack wasn't there until the roofing was completed. I am very concerned about this crack. What should I do about this? And what could have caused the slab to crack overnight?

-- Herman, location not provided

Herman: Small cracks in slabs aren't uncommon. Indeed, most cement will crack at one time or another. The more important question is, how severe is the crack?

If it is a hairline crack, it probably isn't something to worry about. On the other hand, if the crack is wider than one-sixteenth of an inch -- or if the cement is offset (at a different height) on one side -- it could be quite serious. Normally, slabs contain rebar (reinforced steel bars), which helps keep the concrete together even if it should crack. If your builder neglected to put this in, the cracks could be of great concern.

The fact that the crack occurred after the roofing was completed was probably coincidence. In most construction, the roof is supported by a peripheral foundation and the walls, not the slab.

Since you are worrying about this, it would probably be worth your while to call in a professional inspector to check it out. If the inspector indicates that there is a serious problem, you will want to ask your builder to correct it before construction of the home continues. Most builders warrant their construction for several years -- up to 10 years in some states, such as California.

-- Mr. Irwin has more than 25 years' experience as a Los Angeles-area real-estate broker. He is the author of more than two dozen books about real estate and is recognized as one of the most knowledgeable writers in the real-estate field. Mr. Irwin's most recent books are "How to Get Started in Real Estate Investing" and "How to Buy a Home When You Can't Afford It" (McGraw-Hill, 2002).

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