How Can I Keep Water Out of My Crawlspace?

LESLIE: Jim in Washington is on the line with a water-in-the-crawlspace situation. What’s going on?

JIM: Well, we live on the West Coast and like most of the homes out here that are less than 40 years old, we have a crawlspace instead of a basement.

TOM: OK.

JIM: And in December, we had record rain – the most ever – and we discovered, by chance, that we had about 3 or 4 inches of water in our crawlspace.

TOM: OK.

JIM: The dirt floor is covered with plastic. It’s about 1,500 square foot of area, so that was a considerable amount of water.

TOM: Has that drained out?

JIM: Well, we rented a pump and I pumped for a couple of days and then I used my shop vac and took out 5 gallons of water at a time. And yes, it is all out now.

TOM: And we don’t want it to come back, right?

JIM: Well, not only that but I just don’t know what to do to make sure there was no further damage.

TOM: Alright. Well, I have fantastic news for you. It’s so great that your crawlspace flooded after a heavy rainfall, because that tells me that the solution involves your gutters and your grading.

This is not a rising water-table situation. This is a scenario where you have to reduce the amount of water that’s collecting at the foundation perimeter. And usually, that happens because the gutters become clogged and overflow and dump all their water right at the foundation perimeter. Or the downspouts are not extended far enough away and dump water right near the corner of the foundation. Or the grading around the house is too flat or in some cases, even sloped backwards into the house so that the water never has a chance to run away. So when you have a lot of rain and that results in a flood in a crawlspace or a basement, that is always, always, always the cause. So the solution is just to reverse all that.

Now, in terms of damage, if the water was only in there for a short period of time – a week or two and you got it pumped out – I don’t think there’ll be any ongoing issues. If these spaces stay wet for a really long time, you can get increased decay or insect activity. But an occasional flood like that is not likely to have any effect on the house. More important that you make sure it doesn’t happen again by trying to address whatever drainage deficiencies you find.

JIM: Fantastic. Well, that is what I will start doing then. I’ll see what I can find. Thank you. Appreciate it.

TOM: Alright. Good luck with that project.

LESLIE: Thanks so much for calling The Money Pit.