Wet basement? Try to solve it before you spring for more costly options

Most basement moisture problems can be solved through more-effective and less-expensive means than drainage systems and sump pumps.

By Kevin Brasler, Twin Cities Consumers’ Checkbook

September 5, 2020 at 1:30PM

Summer rains can create a lot of headaches with wet basements. But before calling a basement waterproofing contractor, try other remedies.

Many contractors that advertise solutions to basement moisture problems will happily propose fixes that usually involve installation of expensive interior drainage systems and sump pumps — even if you don't need one. But this approach doesn't really solve the problem; it just manages it. Most basement moisture problems can be solved through more-effective and less-expensive means.

Basements get wet when rainwater runs toward the walls of houses from roofs, yards and driveways. You need to force this water away from your home, not collect it once it's inside and pump it out, which is what most contractors will propose.

Start by checking and fixing your gutters. Clean them out, patch any holes, and make sure they slope toward downspouts and have not come loose from the house, allowing water to fall directly from the roof to the ground next to walls. Test gutter downspouts to make sure they spill water at least 4 feet away from the house.

You can extend downspouts for less than $15 each; gutter repairs are more expensive. But these improvements are worth the price, even if they do not fully solve your water problem.

The next step is to inspect the soil around your house and regrade it, if necessary. This is a job you can do yourself, or you can call in a landscaper. The earth around your house should slope at least 1 inch per foot going away from your house for about 6 to 8 feet out from the house. The grading should consist of fill soil with a clay content of 20 to 30%.

Before adding dirt around your foundation, rake out all old mulch, leaves and ground cover. If they are filled over, they will create a shelf that catches water.

Grading costs little — dirt, after all, is cheap — requires no great skill, and should move enough water away from your house to prevent serious harm.

If portions of your yard slope toward your house, you may have to cut a shallow ditch — or swale — to divert water before it reaches the house. A swale is a U-shaped, shallow ditch dug perpendicular to the water flow. Like regrading, it's a fairly simple job.

Regrading or diverting surface water may not always be the best approach. It may cost more than other solutions — for instance, if you have to rebuild an elaborate patio that slants toward your house, or if you have to redo extensive landscaping in the problem area. Furthermore, grading is not a sure cure for leakage problems. Finally, sometimes regrading is a relatively frail solution; a little careless digging in your garden may produce a new source of leakage.

For most homes, the next best approach is to waterproof walls from the outside. To do this, a trench is dug to the depth of the footings of affected walls. Drainage pipe is installed at the bottom of the trench to collect water that seeps from above and carries it to a part of your yard away from your home or into a drainage pit. The exterior walls are reparged and a vapor barrier added. The trench is filled and the surface area is regraded.

Excavating and waterproofing from the outside might be more expensive than installing an interior drainage system. But Checkbook's view is that, unlike interior systems, this will actually solve the underlying problem by diverting water away from walls rather than managing water that has entered the home.

If you need to hire a contractor, meet with and obtain proposals from several of them. Some landscaping companies specialize in drainage work. You can get some insight into a company's performance by checking the ratings and comments posted by area consumers at Checkbook.org. Through special arrangement with the Star Tribune, you can access ratings of basement waterproofing companies free until Oct. 5 via Checkbook.org/StarTribune/Wet-Basement.

Big differences exist in the quality of advice provided by basement waterproofing contractors. Checkbook's undercover shoppers found that different companies may propose drastically different — and in some cases costly and unnecessary — solutions. Don't let them pressure you into a decision.

If your home was built or remodeled within the last few years, check the builder's warranty for clauses on seepage. The builder might bear the costs of repairs.

Kevin Brasler is executive editor of Twin Cities Consumers' Checkbook and Checkbook.org, a nonprofit organization with a mission to help consumers get the best service and lowest prices. It is supported by consumers and takes no money from the service providers it evaluates.

about the writer

about the writer

Kevin Brasler, Twin Cities Consumers’ Checkbook

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