5 easily overlooked old house pitfalls

The roof, the plumbing, the electrical -- all big, expensive trouble-areas in an old house. But old houses have other, less obvious problems that can be every bit as expensive to fix: the foundation, drainage, lead paint, asbestos and underground oil tanks.

1. Foundation

When things get old, they can sag; foundations are no exception.

"It's best to bring a marble with you," says Howard Mayfield, a seasoned Seattle-area home inspector. In some houses, you can drop the marble to the floor, and it will take off like an Olympic skier coming out of the gate. The house may suffer from a sinking foundation or weakness in the joists; whatever it is, it is costly to remedy.

You may find numerous cracks in a concrete foundation, but that is not necessarily a problem; concrete cracks are common. In a nutshell, vertical or diagonal cracks are usually okay, especially if they are slightly wider at the top. If they are wider at the bottom or if the cracks are horizontal, they could be caused by severe settling, and you probably are looking at a hefty repair bill.

Of course, any bowing of a concrete wall is serious and needs professional help.

Another serious concern, said Mayfield, is the old post-and-pier foundation. Instead of a poured concrete foundation, the house is supported by posts set on concrete blocks, similar to deck supports.

"It has no earthquake protection," Mayfield says, referring to the foundation's susceptibility to horizontal movement. Because of the seismic concerns, some lenders and insurance companies shy away from pier-and-post construction. Pier footings can also be prone to settling.

2. Drainage

Old houses often did not have a drainage system around the foundation to take groundwater and rainwater away from the house, according to Maxfield, allowing dampness to enter the crawl space or penetrate the foundation and get into the basement.

Clues to a damp basement include mustiness and mildew or staining along the walls. If you suspect you've got a drainage issue, you can rent a moisture meter for around $20 for a half-day. A French drain can be the solution for drainage problems. Building them involves excavating around the foundation and installing a gravel and drainpipe system to direct water away from the house.

3. Lead paint

Lead, which causes severe developmental and behavioral problems in children, has been banned in residential paint since 1978. That means there is still a lot of it out there. The older the house, the more likely it is to have lead paint. The paint can be either exterior or interior.

Dealing with lead paint is serious business; the Environmental Protection Agency's pamphlet on the subject runs 34 pages. Anything that disturbs the paint should be done by a certified contractor, meaning the prep work before repainting -- either scraping or torching -- and any remodeling and/or repair that disturbs the paint. It also means a hefty price tag.

Even if modern latex paint covers the old lead paint, it has to be specially handled.

4. Asbestos

Inhaled asbestos particles can cause lung cancer.

According to the U.S. Consumer Product Safety Commission, asbestos can be found in old homes in the following places:

• Some roofing and siding shingles
• Insulation in houses built between 1930 and 1950
• Textured paint and patching compounds (banned in 1977)
• Paper, millboard and cement sheets used around wood-burning stoves
• Vinyl and vinyl-sheet flooring and adhesives
• Hot-water and steam-pipe taping and insulation
• Oil- and coal-furnace insulation and door gaskets

Asbestos products are only a danger if they are disturbed or deteriorating -- in other words, if they are discharging particles into the air. If they are in good shape, it is best to leave them alone. But if an asbestos product has to be removed, you need to pay the price for a professional.

5. Buried heating-oil tanks

Buried oil tanks cause two problems:

• They may corrode and leak, polluting the soil and raising your fuel costs.
• An abandoned tank could corrode causing a sinkhole.

If the house has been converted to gas or electric heat, the unused heating-oil tank should be removed, or at least professionally cleaned and capped. But any tank left in the ground can eventually lead to a sinkhole. It can also cost tens of thousands of dollars to replace a leaking tank and clean up the polluted ground.

While an old house can have its charms, you want to be diligent. Look for these pitfalls even before you pay for a professional home inspector to bring in his fine-tooth-comb.