LESLIE: Our next caller is Delbert from West Virginia who wants to talk about installing a French drain, also known as a curtain drain.
Delbert, how can we help you?
DELBERT: Curtain – and I’ve never heard of it called that.
TOM: Well you know, Delbert, Leslie is a graduate of the French Culinary Institute (Leslie chuckles), so she knows all about French drains.
DELBERT: When I bought the house, they said that there was a French drain put in underneath the floor.
TOM: Right.
DELBERT: [Anyway that I got leaking] (ph). So I dug out the whole foundation …
TOM: Well, wait a minute. Why did you dig up your foundation? What caused you to want to shovel the dirt for this?
DELBERT: I had water coming into my basement about three times.
TOM: OK. And did it happen after heavy rainstorms?
DELBERT: Yes.
TOM: Alright, well you don’t need a French drain. OK? Let’s …
DELBERT: Don’t need it.
TOM: No, you don’t need it. Wrong approach. Let me tell you what’s going on. If your basement floods consistent with rainfall, it’s not a rising water table. It’s basically the water that is surrounding your foundation perimeter is not being run, diverted away from the building, so it’s soaking in through the foundation and ending up causing a flood. So you don’t need to put drain tile and pipes and dig up foundations and break up concrete floors and all the other crazy things that people do when they get flooded basements. Those are not waterproofing systems, Delbert; those are water evacuation systems. What we always tell people to do is to look outside. Start outside first because that’s where the water originates.
Leslie?
LESLIE: Yeah, Delbert, you want to make sure that the grading of your property slopes away from your foundation and you want to go down about six inches over four feet. So make sure everything goes away from the foundation.
There’s a couple things you want to do up top as well. Make sure that your gutters are always clean because if they’re overflowing or filled with debris, when water hits it, it’s not going to run into the downspout; it’s going to just sort of spill over and get directly into your foundation area, which you don’t want.
And you want to make sure that your downspouts are not depositing the water directly into your foundation area. You want to make sure that they run at least to 3 feet away from your house itself so that the water gets as far away from that foundation wall as it can.
DELBERT: But the problem is the hillside in front of the house is almost the same level – well, one story tall.
TOM: OK, so do you have a slope into your house, Delbert?
DELBERT: Right. Down (inaudible).
TOM: Alright. Now that’s an opportunity for a curtain drain and what a curtain drain is, if you position it at the bottom of the hill, it’s a trench that’s about 12 inches wide and 12 inches deep in which you have perforated pipe surrounded by gravel with a little bit of grass on top of it. The idea there is so that the water runs down the hill, falls into that curtain drain after it’s installed …
LESLIE: And diverts it away from your foundation.
TOM: Exactly, so it doesn’t – so that’s part of that water management. But the idea of digging down around the foundation and putting in drains is the wrong place to do that. You want to basically capture that water before it gets close to your house. Do you follow me?
DELBERT: Right, right.
TOM: And then run it around. If you manage the water, you’re not going to have a leaky basement problem, guaranteed.
DELBERT: OK.
TOM: Alright. And don’t forget about those gutters. Make sure those gutters are properly maintained because that’s critical as well. And get those downspouts out a few feet and just manage that water. That’s the secret to preventing a wet basement.
Delbert, thanks so much for calling us at 1-888-MONEY-PIT.
jondubb35
Well, it turns out that regrading and new gutters and downspouts was not the permanent solution. About 12 hours after I posted on this website asking if there was more that we could do to prevent basement flooding, our basement flooded. This time, it was completely destroyed. Not one room was dry. We had about 5 or 6 inches of standing water and the water did not stop coming in for about 3 or 4 days!
The grade in our yard had nothing to do with the flood. The water came in from underneath the foundation as the water table had risen so high the only place for water to go was in our basement. Needless to say, we ended up having a drain system and a sump pump installed as the final defense in our quest for a dry basement. If ground water gets in during the next rainfall, the company that installed our system guaranteed they would not only fix the system but also pay for any damages that occur from flooding. I don't anticipate any water getting into our house though! I think we are finally ground/rain waterproofed!!
Sheetal Werneke
I wish I had a crystal ball to help you and many others in your situation. What I can tell you is that the proper drainage is the single best way to prevent a wet basement. It sounds like you have taken every measure possible to have the proper drainage. Hang in there and let us know what happens!