Waterproofing is a treatment of the surface or structure (building) to prevent the passage of water through the basement envelope under hydrostatic pressures.

Sometimes it is necessary to resort to the extreme measure of exposing the basement walls, treating them to make them watertight, and then re-grading the soil.

The conventional system of waterproofing involves membranes. This relies on the application of one or more layers of membrane that act as a barrier between the water and the building structure, preventing the passage of water.

New technology in waterproof membranes relies on polymer based materials that are extremely adhesive to create a seamless barrier around the outside of a structure.


This work should be done only in dry, mild weather. Parge coat (concrete) it is a thin coat of a cementitious or polymeric mortar applied to concrete for refinement of the surface. The newly cemented walls should be properly protected and cured. Freezing or rapid drying of the concrete by sun or wind can damage it and make it worthless. In very wet soils, the parged wall surfaces may be given two coats of hot coal tar pitch.

The intent is to create a contiguous surface by filling surface air voids and bugholes (eliminating Bughole-induced outgassing and to level concrete with extreme rugosity to a level suitable for top-coating with a high-performance protective coating


A "French drain", perimeter drain or land drain is ditch covered with gravel or rock that redirects surface and ground water away from an area. A "French drain" can have hollow pipes along the bottom to quickly vent water that seeps down through the upper gravel or rock. "French drains" are common drainage systems, primarily used to prevent ground and surface water from penetrating or damaging building foundations.

This method is especially suitable on the upper side of a house located on a hillside. Drainage tubing installed around the footings, at least on the sides where trouble is occurring. This footing drain and belt of gravel should drain off all water seepage and prevent the accumulation of water around the walls of the structure. This process is less expensive and widely used mostly in preventive maintenance scenarios.


Where gravity drainage is impossible or impaired, a sump pump may be used to raise the water to a level where it can be carried out through a drain line.

A sump pump is a pump used to remove water that has accumulated in water collecting sump pit, commonly found in the basement of homes. The water may enter via the perimeter drains of a basement waterproofing system, funnelling into the pit or because of rain or natural ground water, if the basement is below the water table level - depression. (In geology is a landform sunken or depressed below the surrounding area).

Sump pumps are used where basement flooding happens regularly and to ameliorate dampness where the water table is above the foundation of a home. Sump pumps send water away from a house to any place where it is no longer problematic, such as a municipal storm drain or a dry well.


In construction, underpinning is the process of strengthening and stabilizing the foundation of an existing building or other structure. Underpinning may be necessary for a variety of reasons:

  • The original foundation is simply not strong or stable enough.
  • The usage of the structure has changed.
  • The properties of the soil supporting the foundation may have changed.

Underpinning the foundation walls: In this method, sequences of holes are dug-out from under the footing of your home. (The footing is the concrete or brick pad which spreads the load of the foundation walls onto the soil.) Underpinning extends the footing of the house to a lower level, which then permits to dig-out the soil from the inside of the basement, without undermining the foundation walls of the house. The process is very laboured intensive, and quite costly.


Benching - in this method, a stable soil slope is maintained between the lowered basement floor level, and the underside of the original footings (to avoid undermining the footings). Then, a steel reinforced concrete "bench" is poured over top of the stable soil slope, to ensure that the soil slope is protected. This process is less expensive; however it leaves you with a concrete bench around the interior perimeter of the basement.