Wet Basements

Keeping your basement dry year round

Spring is right around the corner. Will your basement stay dry? If you have a damp or wet basement the solution does not always have to be expensive. Nearly all moisture problems in basements can be solved with properly functioning gutters and properly sloping exterior landscape. I want to say that again. Most water problems in basements can be remedied with gutters and landscaping! Fortunately these are usually the least expensive fixes also.


Every home should have gutters and they need to be maintained in good operating condition. If your home does not have gutters that is the first thing you need to have done. Have seamless gutters installed. The DIY gutters sold at big box stores are destined to leak so I don’t recommend them. When performing home inspections one of the most common things I put into the inspection report is problems with gutters. Your gutters need to be kept clean. If you have large trees near your house you will probably need to clean your gutters twice per year. If you are unsure of your ability to work safely on a ladder then hire this job out to a pro. There are many gutter screen products available that work well at keeping debris out of the gutters. Seal any leaks that mat develop. But the most important part of your roof drainage system is the extensions on the downspouts.

When doing home inspections I often see downspouts that have no extensions or the extensions are too short and all of the water from the roof is being concentrated in one area and dumped up against the foundation walls. It’s not surprising that it’s getting into the basement. A good rainstorm can dump hundreds of gallons of water through your downspouts. We must get it away from the building. The extensions should be at least 5 feet. Longer is even better. They can be designed to fold up when mowing. If you have landscape edging the water must be discharged beyond the edging. The edging acts as a dam and directs the water back to the house.

Exterior Grade:

The ground around your home should slope away from the house. Ideally 5% which is 6” in 10 feet. This is not always possible but you must get as much as possible. You are sometimes limited by how high the siding is above the ground. We like to keep 6” between siding and soil or close to that. Very old homes often have two to three feet of foundation showing. This is a good thing. Newer homes also seem to be improving in that aspect but many homes built in the 50’s and 60’s have very little foundation showing. They are often built on level lots. Sometimes this means you have to dig a swale to allow water to drain away from the home. Sometimes neighbors get together and put a swale on the property line which will benefit both properties. A French drain can be installed in this swale which is a pipe and gravel to aid in drainage. The soil around a newly built house often settles in the first year or two. When doing home inspections I sometimes find this settled area filled level with mulch or rock so it looks good but doesn’t help the problem.

If your home is at the bottom of a hill or is the lowest house in the neighborhood more extensive grading may be needed. For the few houses where proper gutters and grading don’t solve the moisture intrusion then drain tile and a sump pump are needed. Drain tile is now required for new construction but the sump pump is generally not. For existing construction interior drain tile and pump can be installed. This is best done before finishing of basement.