Housejacked: An Unsettling Tale

Because inspectors are not necessarily trained structural engineers, they might not catch the problem, or grasp the extent of it. Although my husband noted extra mortar and stair-step cracks above the garage before we purchased, our inspector said that the mortar was old, so the settling must have been as well. Calling in an expert might be expensive, but it is likely to cost less than being stuck with the problem later.

· Sniff out water damage. Just as a river gradually erodes its banks, water left to run down or pool around a house can weaken mortar or rot framing. Any outside walls subject to runoff should sport flashing and gutters, and the ground should slope away from the house. Schied advises checking for low horizontal cracks, which indicate long-term water damage.

Even if you don't see cracks or water in the basement, a musty smell is a dead giveaway that water has cozied up to the house and stayed awhile. Waterproofing on most basements is good for only 20 years or so. Unless homeowners employ other drainage measures, the concrete, which Shuster says works like a paper towel, will suck up water until it's saturated. Running a dehumidifier in such cases is akin to blow-drying a paper towel that continues to sit in a puddle.

· Look for bowing and sagging. Interior walls can suffer the same fate as people lying on old mattresses: They are pulled toward the center. A floor exposed to moisture, especially one over a crawl space, tends to warp downward, dragging the walls along with it. A simple level can reveal which walls are leaning and whether a pattern exists.

· Distinguish between normal and severe cracks. Plaster is one of the first clues to damage, exhibiting cracks where the wall is being pulled in different directions. According to local plaster and stucco expert Reggie Bullard, of R.T. Bullard in Woodbridge, buckling and horizontal cracks generally seen near doors and windows indicate weak plastering and can be easily fixed. However, deeper diagonal cracks signal problems with the walls themselves.

· Check for stubborn doors and windows. Those that don't open and shut as they should are a clue that walls have shifted, Schied said. On the wall where we noted the extra mortar and cracks, we were unable to lock the window. That the window was newer should have clued us in that the settling had continued.

· Inquire about retaining walls. Because retaining walls are prone to move, their very presence threatens the soil surrounding a house. Of highest concern are those recently constructed or replaced, which have loosened the dirt and therefore traumatized the nearby foundation. It is especially critical that the dirt be tamped down after any construction to reduce the possibility of settlement. Our neighbor informed us that when the retaining wall near our garage was replaced a year before we moved in, the workers merely shoveled the dirt back into the hole.