Our foundations are waterproofed with the Tuff-N-Dri system offered through Foundation Systems, Inc. of Akron. The Tuff-N-Dri waterproofing system combines a sprayed-on elastic membrane with Warm-N-Dri protection, drainage and insulation board. This fiber board relieves hydrostatic pressure on the wall, drains water, and insulates. It moves the cold surface to the outside, a big factor in eliminating condensation and mildew. A fifteen year guarantee is provided with the Tuff-N-Dri system.
Even more important to keeping a basement dry is the foundation backfill process. We firmly believe a foundation should be backfilled with washed gravel (not dirt) from the basement floor level all the way up to within 2-3 of the finished ground level outside of the home. This does several things. Any surface water which makes its way up against the foundation (from a misdirected yard swale or from water cascading over a clogged roof gutter) and which penetrates the top 2-3 of lawn surface can easily drain through this gravel down to the perforated footing tile. This is especially important, if not critical, with soils having high clay content. Secondly, this type of drainage prevents trapped water and saturated soil next to the foundation from building up horizontal hydrostatic pressure against the wall. This pressure will crack walls, cause leaks, and in a worst case, collapse the wall inward.
Despite these facts, most local building codes require only 18 of coverage from the bottom up. The additional cost for full height backfill is approximately $3,000. For this reason, most builders provide only the minimum coverage required by codes.