Over the last month, we had a whole lot of rain. So, don't you know, I spent a whole lot of time on the phone, talking to people about their wet basements. Understand, I enjoy few things more than talking to people, but when I go through the wet-basement-support script for the tenth time, I start thinking, I ought to write this stuff down. So, here it comes:
Everything I know about fixing wet basements. Cut it out, save it, and stick it on the fridge.
First thing you need to know: Here in the South we get lots of rain, coming in fronts that travel upward from the Gulf and westward from the East. Seattle, known for its rainy weather, actually gets less rain than our region, but the difference is that Seattle gets mists and soaking rains, while we get spells of frog-strangling, gully-washing rain, the kind of rain that makes tides in the sewers. It's almost impossible to build a house that can keep that much water out.
If your house is old enough to have a limestone foundation, the basement won't just leak sometimes. It'll leak pretty much all the time.
If your house is relatively new, and if the people who waterproofed the basement walls were very careful, and if you scrupulously maintain the gutters and drains, there is a tiny little chance that the basement won't leak.
From everything I know, you homeowners should assume that your basement will leak. The question is: How can you make your basement leak less? Well, I'm going to tell you.
Clean out your gutters. Better yet, get somebody else to clean them out. At my house, cleaning the gutters involves climbing a ladder, getting on a roof, pulling the ladder up to the roof you're on, and then climbing the ladder again - not just once, but three times. That's acrobat work, and I'm not suited to it. So I hire a gutter cleaner.
Now, you might be wondering, What do the gutters have to do with my wet basement? Well, most likely, that's where most of the water in your basement is coming from. It spills over the edges of the gutters, cuts a little trench along the foundation wall, and the next thing you know, you've got a perfect basement-wetting system.
Once you've got the gutters and downspouts clean, make sure the water from the downspouts actually goes away from the house. The best way to do this is to attach some cheap, black plastic drain pipe - made especially for this purpose - to the ends of the downspouts. Run the pipe downhill, away from the house. I suggest burying the ugly pipe in a trench, then covering it up with mulch.
If you've got an old gutter-and-downspout system - with the downspouts run into clay drain pipes that disappear underground - you need to do a little drain remodeling. Old clay drains are typically clogged, broken or both. Water that starts out in the drains ends up in your basement. So, you have to take the downspouts out of the old drains. You'll probably have to break up the clay pipes to get to the ends of the downspouts. Then, hook the downspouts up to cheap, black plastic drain pipes, as described above.
Once you've got the gutters and drains fixed, make sure that the soil around the house pitches downhill, away from the house. The soil should drop at least six inches in the first ten feet. If you don't have ten feet to work with - which might be the case if there's a wall or a drive in your way - you still need to get the six-inch drop.
If you do all this, and you still get water in your basement, you're probably going to have to do something fancy and expensive. A sump pump is the only decent low-cost water-removal option. The problem with a sump pump is that it just gets rid of water that's already in your basement. It doesn't keep water from running through - and damaging - your foundation walls.
The usual fancy, expensive solution is a perimeter drain system. Perimeter drains catch underground water before it gets to your foundation walls, then direct the water away from the house. The problem with these systems is that they have to be designed carefully and installed perfectly, or they just don't work. Most of the ones we see don't work.
As far as I know, the best last-ditch defense against basement water is a basement de-watering system. Every time we get heavy rain, you'll see ads for these things on TV. Here's how they work: Somebody drills holes through the base of the foundation wall, then installs a drain along the inside of the foundation wall. The drain looks like a decorative baseboard. Water flows through the holes in the foundation, behind the fake baseboard, and into a sump pit. A pump in the pit shoots the water back outside, where it belongs.
I've seen a few dozen of these systems, and all of them worked. If I had ongoing basement water troubles, I'd get one of these systems. But I still wouldn't count on the basement staying dry, and I wouldn't put anything fancier than a ping pong table on the basement floor.