Methods for Preventing Water Penetration. What's the simplest and most common method used to divert water away from the property? Gutters and downspouts are used to collect and divert roof water in conjunction with proper grading techniques for surface water around the home.
What if water is still getting into my house? Annually cleaning your gutters and installing extensions on the downspouts will typically address any roof water. Moderation in the amount of water sprayed into mulch and flower beds also help to prevent water penetration. Another common source of water is floor drains in recessed exterior stairwells or patios. Annual cleaning of these drains will ensure that they can perform their designed function of directing water away from the foundation.
In more extreme circumstances, typically houses at the bottom of hills or other high surface water run-off areas, swales or other advanced grading techniques may be required to divert surface water around the perimeter of a home. These are typically installed during the final grading stage by the builder of the home.
Methods for Controlling Groundwater. Not all water that enters a house comes from the roof or ground surface. Subsurface water, or groundwater, which is typically the result of a high local water table, may try to upwell into a basement through the slab from underground. In a basement this water is most easily controlled by a sub-slab sump and electric pump system that collects underground water and pumps it to the surface and away from the foundation area. Occasionally, depending upon the size of the basement, a second sump system may be required.
Method for Controlling Excessive Moisture Vapor. All foundation materials are porous and will allow some moisture vapor to pass through from the exterior. In addition, the cooler temperatures in crawlspaces and basements create a condition which tends to draw in the moisture through condensation.
In homes where excessive moisture is present, some control method should be used to prevent problems with wood destroying insects and fungus. In basements, the most common method for controlling moisture vapor is with a dehumidifier. In crawlspaces, moisture vapor penetration usually comes through the soil floor and can be adequately controlled with a proper vapor barrier and crawlspace vents.