What causes poor basement waterproofing drainage?

For problems caused by poor drainage around the foundation of the house, there are some steps that should be taken before attempting any repairs.

Step outside and inspect your house. Do you have roofline gutters? If so, where do the downspouts drain the water? They should carry the water either to a storm sewer (where permitted), or a dry well. If there is neither of these, there should be splash guards at the bottom of the downspouts that will carry the water at least 8 to 10 feet from the house. Check the gutters and clean them of leaves, nests, and other debris.

During a rainstorm, go outside and check  for breaks or leaks. Repair any damage to the gutters caused by ice and snow. Many basement flooding problems caused by poor drainage have been corrected by the proper installation and repair of roof gutters and properly positioning the downspouts.

Should the basement still leak after making the repairs, it should at least be less than before. (Not much consolation, but a good gutter is a worthwhile investment in any case.)

Next check the grade of land away from the house. There should be a gradual sloping away so that the surface water will tend to run off before being absorbed into the soil. You can check the grade using a straight 2? x 4? x 8´ board and a four foot level. Lay the board perpendicular to the foundation and place the level on the board.

The bubble should be off center toward the house. If the bubble is dead center or off center away from the house, you probably have some regrading to do.

Before calling a contractor for several loads of fill, it is a good idea to examine your soil. You can do this yourself or get the assistance of the local agricultural agent or a representative from the U.S. Department of Agriculture Soil Conservation Service (SCS) who deals with homeowner problems. In many areas of the country, SCS has detailed soil maps and can be of great assistance in helping you decide what action to take to improve the drainage around the
house.

Dig out a hole down to the base of the footing. This will serve two purposes. One, it will show what you have for soil and its relative moisture-holding capacity, and two, it will show what your house has as waterproofing on the exterior wall.

Even if the walls appear well protected, poor workmanship frequently is the cause of basement leaks. Improper mixing of cement with too much sand and other time- and cost-saving “shortcuts” may have kept down the purchase price of the house at the expense of major repairs sooner and more frequently than expected.

If the soil in the test hole is loose, crumbly and easy to shovel, then you have a medium to light loamy or sandy soil. These soils will provide good drainage under most conditions. With adequate waterproofing on the wall, simple surface regarding should solve your problem.

If the soil is extremely hard-packed with a heavy clay texture, then it is likely that it is partly responsible for your water problem, and simply regarding will be of little value.