Basement Waterproofing

Moisture problems are
prevalent all over North America. They are viewed as one of the
single largest factors limiting the useful service life of a
building. Wet basements are the most frequent complaint of
homeowners. Over 60 percent of basements have moisture leakage and 38
percent experience mold and fungus growth due to an elevated level of
moisture.
Finding the cause of
the problem is absolutely essential to its cure. Though trying to
find the source can be daunting we hope the following ideas and tips
will be helpful:
Identify the Source of Moisture
- If, after a heavy rain, you have standing water in your basement, it’s likely from a leak in the foundation.
- If you have water stains on the ceiling you most likely have a burst water pipe.
- If you can’t
identify where the moisture is coming from, whether it’s
seeping in from the outside or condensing inside, tape a twelve-inch
square of aluminum foil to a wall that is prone to dampness, sealing
all four sides to make the surface behind the foil airtight. In a
day or two, if the side of the foil that was against the wall is
wet, the problem is seepage. If the outside is wet, it’s
condensation.
Take Preventative Action
- Lawns that are
flat or slope toward your home invite surface water to drain down
against the basement walls allowing water to enter through the
cracks and pores causing wet spots on the walls. Make sure the
ground around your house slopes away from the foundation - about one
inch per foot. Extend the slope for at least ten feet. If this isn’t
possible then surface drainage should be intercepted and rerouted
some distance from the house.
- Defective,
clogged, or nonexistent gutters and downspouts permit rain
water to form puddles and wet soil against basement walls. Install
gutters and downspouts where needed and keep them clean of debris.
Invest a few bucks in a gutter shovel; the best invention since
sliced bread and designed to slide along the gutter and scoop away
debris. Or, for a maintenance free gutter, install gutter toppers,
screening, or a basket-shaped wire strainer over the downspout
outlet. To prevent high concentrations of water forming at the point
of discharge, use a concrete gutter or splash block to carry the
water away at a slope of one inch per foot.
- If you have a sump
pump, make sure it’s working properly.
- If you find
condensation, or sweating, on cool surfaces in the basement such as
walls, floors, and water pipes, you should insulate the water pipes.
- Do NOT close your
subarea vents during the winter because you think it will keep your
house warmer. The purpose of foundation vents is not to adjust the
energy efficiency of your home. It is to prevent humidity caused by
ground moisture from condensing on the structure and rotting the
wood framing. Open vents are more important in the cold weather than
in the summer, however open vents should be maintained at all times
regardless of the season.
- To reduce indoor
humidity use ventilation fans in kitchens and baths to control
moisture. Make sure the fans are venting directly outside. Make sure
your clothes dryer is being vented outside. Check the vent duct and
make sure it’s attached securely to the dryer. Clean the vent
duct at least once a year.
Steps You Can Take to Prevent Future Moisture Problems
- Install a sump
pump where gravity drainage is impossible or impaired. Sump pumps
are used to raise the water to a level where it can be carried off
through a drain line.
- Apply
waterproofing compounds to the interior walls. Keep in mind,
interior wall treatment will not work if major exterior water
conditions still exist.
- Exterior injection
of waterproofing substances into the space between the soil and the
basement wall. The substance swells to many times its dry volume
when it is put into slurry form. The slurry will tend to penetrate
and plug cracks where water might also find a path to the basement
interior, thus reducing the flow of water.
- Excavation.
Sometimes it is absolutely necessary to take the extreme measure of
exposing the basement walls, treating them, and then re-grading the
soil.
A dry basement will
protect the investment you made in your home as well as enable you to
use the space for additional living or storage space. The following
links may be useful in your journey to a healthier and dryer
basement:
Articles related to Basement Waterproofing