I don’t know why, but the urge to finish a basement seems to be right up there with urges to survive, eat, and reproduce. If you pick up 10 do-it-yourselfer magazines, at least nine of them will have an article on finishing a basement. In our home inspection business, when we have a customer who’s buying a basement house, the first question we hear is, ”Can I finish the basement?“ Folks get one look at their little underground lair, and they get dizzy with dreams of a pool table, a workshop, or a combo TV/rollerblading room for the kids.
You would-be basement finishers, listen to me: This is Tennessee. We get about 4 feet of rain a year. That rain is drawn to basements the way fresh-washed dogs are drawn to dead things. So when people ask us if they can finish a basement, our smartypants answer is, ”Sure. Just don’t put anything down there that you wouldn’t put at the bottom of a lake.“
Sooner or later, most basements in our part of the world get wet. I know, I know. Some of y’all are thinking: This is America. Surely, the country that crashed two Mars landers in a row can figure out how to keep a basement dry.
Well, we have figured it out. On paper, anyway. When we build a new house, all we have to do is waterproof the outside of the foundation walls, put in foundation drains, and that’s that. The problem is in the execution.
Most of the time, some hurried or misguided member of the labor force will find a way to screw up the waterproofing job. Add to that the recurring theme of burying the outlets of the foundation drains, and you have a system that catches water, and actually directs it into the basement.
With older houses, there’s a pretty fair chance that the walls were never waterproofed, and there’s no foundation drain system. Before WWII, a whole lot of houses were built on stone foundations, which are leaky as can be. In these houses, it’s all but certain that some water’s coming in.
All this means that it’s probably not a good idea to finish a basement, at least until you’ve seen it stay dry for a couple of years. Even so, you should do all you can to keep the basement dry. When a basement’s all damp and dank, mold and fungus can grow. Some of that mold and fungus is bad for you.
First step to keeping a basement dry: Make sure the soil around the house pitches away from the house. The ground should drop at least six inches in the first 10 feet. If you live in a neighborhood where the houses are close together, you may not have 10 feet to work with. If that’s the case, you still want the ground to drop at least six inches. Simply put, your house should be sitting on top of a little hill, which is at least six inches high. Got that? Good.
Second step to keeping a basement dry: Make sure the gutters, downspouts, and drains are clean, pitched properly, and free of leaks. Why is that? Well, when it rains, a whole lot of water flows off your roof. If the gutters are clogged, or pitched so that water leaks out of them, water runs out and pounds on the ground next to your foundation walls. Next stop: Basement.
If you ask me, every downspout should run into a drain pipe that takes the water well away from the house. I say buy some of that cheap black plastic drain pipe that attaches to downspouts, run it through the flowerbeds, and throw mulch on top, so nobody has to look at the ugly pipe.
Don’t rely on splash blocks. Generally speaking, they are lame. If you’ve just got to use splash blocks, turn ’em so the little curb is at the top, not at the bottom. I’m amazed that I have to explain this. I know, that’s the way they were when you bought the house. That’s because builders install ’em assbackwards, in a vain attempt to keep downspout water from washing away the newly planted grass. But it’s like the cotton in an aspirin bottle. You should throw away the cotton, and turn the dang splash blocks around the right way.
If you have your house on top of a little hill, and if you have your gutters, downspouts, and drains fixed right, you might just end up with a dry basement. If not, you’re still not out of options.
You can call one of those basement de-watering companies. They’ll come and drill holes in your foundation walls and install special water-catching baseboards. The fancy baseboards will direct the water to a pump, which will shoot the water back onto the ground outside. From what I’ve seen, these systems work, but they cost about as much as a used Plymouth Breeze. Not exactly cheap, but it’s worth it to keep your basement from smelling like Disneyland’s Pirates of the Caribbean.