CHAMPAIGN — If record-breaking rains caused by remnants of Hurricane Isaac come to East Central Illinois this weekend, conditions could be perfect for flooded basements, even those that have never flooded before, said one expert on moisture in roofs, walls and foundations.
Bill Rose, senior research architect at the Illinois Sustainable Technology Center in Champaign, said the way homeowners can prepare is to assume that their basements will take on water. Rose also wrote a book called "Water in Buildings," which is exactly what could happen to local homes if the area actually gets 6 inches of rain.
That's because when there's a drought, the clay in soil shrinks, and you see large cracks. Water goes down those cracks.
The largest cracks caused by drought, though, are those that form when the soil pulls away from your foundation, Rose said. It usually takes awhile for moisture to swell that soil when it rains, which means water will flow down that crack and into basements.
"I expect that we're going to get a lot of water to get in those cracks," Rose said.
Also, if soil or other debris has fallen into those cracks, it can swell and actually push basement walls inward.
That seems to especially happen with block foundations. With rains after the 1988 drought, Rose said, he heard reports that people actually heard their foundations cracking.
"Ideally, you would want the soil to come back to its normal size slowly and softly, rather than in one big swoop," Rose said.
Rose said the best thing you can do when anticipating heavy rain is making sure rainwater is pushed as far from your foundation as possible. Here are some tips on how to do that and deal with possible flooding:
— Make sure your gutters and downspouts are shooting water as far from your foundation as possible. If you need to, head to the hardware store and pick up some downspout extenders or plastic piping.
— Check your gutters. Because the leaves haven't started falling in earnest yet, this isn't a huge issue. However, it doesn't hurt to check, Rose said, especially where gutters connect to downspouts. You don't have to remove all debris, just clogs the size of a tennis ball.
— Clean up your basement to anticipate flooding. Get items off the floor and sweep before the rain starts.
— Keep cleanup tools on hand. If you have a wet/dry vacuum, make sure it's clean and ready to go, and scope out a safe place to plug it in. Make sure you have a dehumidifier, as well. Flood cleanup includes pumping out water, vacuuming up what's left and then giving your basement as much ventilation and dehumidification as you can.
— Check your sump pump. You can pour in a couple of buckets full of water to test it, or just pull up on the floater, Rose said, to make sure the pump turns on. Make sure the float moves freely. Also, make sure the discharge is being piped outside, away from your foundation. Buy a PVC extender or plastic pipe if you need to.
— Consider buying a second sump pump. You can buy models that sit on the basement slab, Rose said. Just make sure you have a way to get the discharge outside and away from your foundation.
— If you have a crawl space and there's anything in it, get it out. You can install or even set a sump pump in a crawl space. If it floods badly and stays wet, Rose recommends buying a quart of mineral oil at a drugstore and pouring it on top of the water. That helps prevent the water evaporating into the house, which can make it really humid or even cause mold to grow inside.