Once you decide on a solution, how do you get the work done?

Grading, Gutters, and Downspouts

You can probably DIY gutter, downspout, and grading improvements.

For downspout work, you can buy downspout pipes and joints, flexible plastic drainage pipe, window wells, transparent window well covers, and other materials from home improvement stores. If you want expert help with downspouts or gutter work, check our ratings of gutter cleaners and gutter installers.

For grading work, you can do it yourself, hire landscaping companies or consult companies specializing in drainage work. Before hiring a contractor, have several companies send out estimators to look at your problem and provide proposals and price quotes.

Sump Pump

If you want to install a sump pump or two without perimeter drainage piping or other features, use a plumbing contractor. Many plumbing outfits offer free estimates on sump pump installations, with prices usually ranging from $1,000 to $2,000.

Interior and Exterior Drainage Systems

If your problem is intractable enough to warrant an interior or exterior drainage system, you probably need to hire a basement waterproofing contractor or drainage specialist. The ratings and reviews from our surveys of area consumers will help you get started.

Be warned: If you do need to hire a waterproofing contractor, get proposals from more than one. Different companies likely will propose drastically different—and in some cases costly and unnecessary—solutions. Many companies use high-pressure sales tactics. Don’t let anyone pressure you into a decision.

When you review ratings of basement waterproofing contractors, keep in mind that they tell you how satisfied (or dissatisfied) customers have been with the work. But some companies do an unnecessary job well, and may not have recommended the least expensive or best solution. If homeowners go for pricey cures and they work, a company will score high in terms of customer satisfaction but may be a bad place to go for advice.

Many basement waterproofing contractors primarily install—and almost invariably propose—interior drainage systems with sump pumps, rather than regrading or excavation work. Why? Aside from the fact interior drainage systems and sump pump installations generate more revenue than applying a few inches of topsoil, regrading and excavation work takes more expertise to do right. And even well-done regrading and excavation work doesn’t always solve leakage problems right away; additional work may be needed.

On the other hand, jackhammering floors along the base of interior walls, installing drains, and directing water flow to a sump pump takes little expertise. It’s also easy to guarantee, and guarantees sell. Drainage specialists, on the other hand, sometimes have to try one approach, wait to see if it works, and if not, try something else. It’s why the few basement waterproofing contractors that actually perform exterior work usually won’t guarantee it.

When choosing any contractor, check payment schedule: It should allow you to pay most or all of the cost after completion. This gives you leverage to make sure the job is completed promptly and neatly. The best arrangement is to hold final payment until after the first heavy rain so you can find out how well the job holds up.

If you must install an interior system, compare the guarantees offered by companies that bid on the work. Of course, a guarantee should protect you if the system doesn’t work—but you still have to enforce it. In this field, don’t be too impressed with long guarantees. If a company goes under, its guarantee won’t do you much good—and waterproofing companies go under all the time.

Also, beware of technicalities in guarantees. Some impose an annual fee to keep the guarantee in force—an easy-to-overlook requirement. In addition, warranty coverage of sump pumps varies. Some warranties cover the pump for as long as they cover the underground system—perhaps five years or more; some cover it for a year or less.

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