Basements are imperfect structures built in soils that vary. Water in the soils can leak into the basement through the walls, floors, and joints between them and become a problem. A wet or even just damp basement is unsuitable for finishing or even storage. Whether you plan to completely refinish your basement for added living space or use it as a storage area, you need you need it to be dry. Otherwise, moisture could get into the building materials and/or storage and cause mold, mildew, rot, bad smells, and damage to floor coverings, furniture, and stored personal items.
Waterproofing and drainage considerations are especially needed in cases where ground water is likely to build up in the soil and raise the water table. This higher water table causes hydrostatic pressure to be exerted underneath basement floors and against basement walls.forcing water in through cracks in foundation walls, through openings caused by expansion and contraction of the footing-foundation wall joint and up through floor cracks. Hydrostatic pressure can cause major structural damage to foundation walls and is likely to contribute to mold, decay and other moisture related problems.
Over the years, contractors and engineers have developed a wide variety of methods to keep basements dry.
Waterproofing Your Basement with Interior Sealants
In poured concrete foundations, cracks and pipe penetrations are the most common entry points for seepage. These openings can be readily sealed from the interior. Epoxies or urethanes are pressure injected into the openings, penetrating the foundation through to the exterior, thereby cutting of the path of the seepage. These repairs will last for a long time.
Where hydrostatic pressure is present, masonry foundations, interior sealers will not provide permanent protection from water infiltration. Interior sealers are good for preventing high atmospheric humidity inside the basement, from absorbing into the porous masonry and to prevent spalling, a condition where constant moisture breaks down masonry surfaces causing deterioration and shedding of the concrete surfaces.
Interior waterproofing inside, using coatings, works well where condensation is the main source of wetness. It is also quite effective if the problem is minor dampness. Major leaks can’t usually be handled by inside coatings
Interior water drainage
When the foundation is constructed of concrete blocks, an interior drain tile system, described below, can capture the water entering the block system and drain the water into a sump. Typically, weep holes are drilled into the lowest course of block, allowing the drainage to occur. This system will provide a dry and moisture free basement for years to come.
Interior water drainage is a widely accepted technique in mitigating basement water. Interior drainage systems function by draining underground water from alongside the foundation footers and underneath the basement floor into a floor well where a sump pump will then pump the water from the basement.
Waterproofing your Basement with Exterior Waterproofing techniques
Exterior waterproofing prevents water from entering foundation walls. Prior to the 1980s much of the original exterior waterproofing was actually damp-proofing using a degradable asphalt-based covering. Waterproofing an existing basement begins with excavating to the bottom sides of the footers. Once excavated the walls are then sealed with a waterproofing membrane and new drainage (weeping tiles) are placed at the side of the footing.
Over the past ten years, polymer-based waterproofing products have been developed. Polymer-based products last for the lifetime of the building, and are not affected by soil pH. Polymer-based waterproofing materials have the advantage of a low enough viscosity that they can be sprayed directly onto a wall, are very fast curing, and are semi-flexible, allowing for some movement of the substrate.
Thomas P. Ryland offers a variety of basement waterproofing solutions to handle all your waterproofing. Needs.