Mary Heidbrink, Express-News Staff Writer –

It appears like a route on a roadmap, a squiggly line inching from the corner of the door toward the ceiling. It gets wider, like an expanding thoroughfare.

Then, the door that had been a little stubborn won’t open at all.

Is it a sure sign of doom for a homeowner, the signal of foundation failure? Or is it just another sign of a long dry spell?

It all depends, and so does the action you take.

CONCRETE SLAB

•What’s under the slab? If it’s limestone, rest easy (unless you’re trying to dig a hole in the garden). If you’re not sitting on rock, investigate further.

•Clay soil is often the culprit in shifting foundations because of its plasticity. Think of a sponge that plumps up when it’s full of water and shrinks and curls when it dries. When this happens to the ground under your house, it can cause the foundation to heave or sink.

•Proper site preparation mitigates the effects of shifting soil. The builder should remove all soil and tree roots and replace it with nonexpansive fill material.

Signs of trouble

•Cracks that are 1/8 inch wide or wider.

•Floors that are out of level at least 1 inch per 10 feet.

•A crack in a wall or a sticky door indicates settling, not a cracked foundation. Of more concern: a combination of cracks inside and outside or cracks and jammed doors.

•If there are wide cracks in the walls or a door that won’t open, consult an engineer. An expert’s opinion will cost about $500.

To water or not to water?

•Watering around the perimeter of the foundation can help, but before hauling out the hose, use a carpenter’s level to check the floors inside the house.

•If the floor is fairly level, watering around the foundation can help keep it that way.

•To water, line the perimeter of the foundation with soaker hoses. The hose should touch the foundation. Turn water on a quarter turn and water two to three times a week for two to three hours, keeping soil consistently moist, not muddy.

•Water the side of the house that is lower than the rest.

•Monitor progress using a level on the floor, and be patient. It likely will take months to see results.

Repairs

•A foundation company will dig under the edge of the slab and install concrete piers 10 to 15 feet deep, leveling the foundation and isolating it from the problem soil near the surface. If work is needed under the middle of the foundation, workers will tunnel under the slab or install piers from inside the house.

•Leveling can cause additional cracks in drywall. Sometimes it can be patched; sometimes it will need to be replaced. New doors might be in order if existing ones had been modified to fit crooked openings.

•Foundation repairs average about $12,000, and typically have a lifetime guarantee.

PIER AND BEAM

Different underpinnings, same symptoms. Cracks and sticky doors still might indicate a faltering foundation.

Different care

•Standing water is the enemy, causing soil to expand or rotting cedar piers.

•Monitor the perimeter to make sure water drains away from the foundation.

•Pier and beam foundations don’t need to be watered because the crawl space under the house keeps moisture uniform.

Repairs

•Repairs, which usually consist of replacing piers, average about $8,000.

•Drywall can buckle in the leveling process. Doors might not fit, and windows might not open when the work is done.

•Repairs typically have a lifetime guarantee.

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