8 Ways to Get Your Basement Dry

From The Master Plumber Blog

With the 10 inches of rain dumped in eastern Massachusetts this past week, I’ve been hearing lots of stories about basements.  Agents are asking each other if they’ve got water in their basements, and clients are loving looking at potential homes right at the time that any leaks and wet basements would be easily visible.  From a few inches of water in the city where street water is quickly drained into the ocean to two-foot deep underground swimming pools in the suburbs, lots of people are seeing water in their basements.  Here are some ways in which you can start keeping your basement dry, placed in order from easiest to implement to most complicated.  Note that managing water outside your house via gutters and landscaping will solve the majority of wet basement issues.

1. Clean your gutters out.  When a gutter spout gets clogged or a gutter gets blocked, water from the roof can pour over the gutter at the blockage point and fall right next to the house, many times digging out a trench in the dirt or wearing away the concrete.  Either way, the water collecting next to the house eventually seeps through the foundation and becomes water in the basement.
2. Divert your gutter downspout away from the house.  You can add hoses to bring the water from the downspout away from your house, or you can create or buy a little trench that carries it away as well.  If your home is on a hill, then you can even bury the hose under ground and have it pop out away from your house so you don’t have to deal with moving the hose every time you mow the lawn or walk around the house.
3. Regrade your yard.  This entails moving or adding soil such that the ground slopes away from your home such that when rain falls or gutters drain water out near the house, the water will flow away from the foundation walls.  Make sure to use soil, and avoid sandy mixtures or gravel, as these materials just allow water to flow straight through them.
4. 

   From Ask The Builder

   Add a linear french drain around your house.  This works best when your house is on a slope and water comes down towards your house.  The drain should be dug out such that it intercepts all the water coming down the slope, and brings it around your house until it’s downhill from you.  The Ask The Builder website has a cross section diagram of the drain as well as a picture of where the drain should be placed relative to the house.

5. 

   From Drycrete Waterproofing Ltd.

   Add a french drain inside your basement with a sump pump system.  This drain collects all the water in the floor of your basement and brings it to a dug out pit in the corner of your basement.  Inside this pit is placed a tank with a sump pump which automatically pumps out water whenever it reaches a certain level in the pit.  You should have a battery backup system for the pump, since many times flooding is accompanied by power outages.  Some people will set up a sump pump alarm with their security alarm system so that they can be warned when the power goes out and there is water in the sump pump that needs to be drained–this allows for people in areas where the power can go out for longer periods to rush home and turn on the generator for the sump pump.

6. Place an elevated subfloor on the floor of the basement.  Once you’ve added a french drain inside your basement, an elevated subfloor is the next step.  This can be done simply with treated 2×4 laid down flat on the floor and placing moisture-proof plywood over, or with specialty products like the Dricore Subfloor.  Both methods leave an air gap between the finished flooring of the basement and the concrete floor, which does two things.  First, if there’s ever a situation where the sump pump goes out or excessive rain and a little water actually collects on the floor, you’ll have an inch or so of tolerance where your basement flooring and furniture won’t get wet, and after the rain stops or the sump is fixed, the water will go back down with no one the worse for wear.  Second, it lifts the finished flooring off the concrete which lessens the feeling of basement dampness that can come from being right on the concrete.  Generally people will place a sheet of plastic over the subflooring, then place their carpet or laminate/engineered flooring on top of that.
7. Add a french drain right on the exterior of the foundation walls.  This is a lot of work, as the ground needs to be dug out to the bottom of the foundation.  However, this is very effective given that the water is pumped away from the home before it gets inside.  This type of work would be important if the linear drain wasn’t an option due to the grading or yard geography, and you were getting chronic water in the basement.
8. Waterproof the exterior of the foundation.   Some people will waterproof the interior of the foundation walls, which is useful to prevent moisture seepage, but if there’s any kind of water pressure, the water will come through interior waterproofing.  Plus, it’s not good for masonry to be constantly soaked in water, so if you can, it’s better to waterproof the exterior of the foundation.  As in #6, you have to dig out the foundation in order to get at the walls.  There are several methods of waterporofing.  Dry Crete Waterproofing has a product called Delta-MS which is a membrane that is completely waterproof but leaves an airgap between the membrane and the foundation, which leaves the foundation masonry completely dry–and if any moisture were to get in between the membrane and the wall, it would just flow down into the french drain system that is at the bottom of the foundation.  Other companies will just spray on a tar-like mixture to seal the foundation.

There are a ton of products and people out there that will promise you a completely dry basement.  Always take things with a grain of salt–keep in mind that the only way to prevent water from getting into your basement is to get rid of the water.  Watch out for products that you can just paint on to the inside of your walls that promise anything besides a change of color.  You gotta get rid of the water first–which is why just adding some dirt around the house and moving downspouts around tends to fix most peoples’ problems.  If you still have water after those two quick fixes, then start looking into more serious work and consult a professional contractor to see what your best path would be.