We get asked a lot of questions regarding waterproofing of a homes foundation and why we prefer to always waterproof from the exterior of the wall rather then the interior. The reason being is that interior waterproofing in the Hudson Valley can cause more harm then good. Especially because of the frost freeze cycles our area goes through in the changing of the seasons.
Leaking basements always start from the exterior in. Older homes that were built on monolithic slabs tend to leak at the cove joint (the small joint between the floor and the wall), block walls tend to leak because of they're porce and allow water in if not coated properly after installation and poured walls can leak from hydrostatic pressure causing them to surface crack. Not to mention all the other factors that contribute to these issues.
Now onto why we do not recommend going to the hardware store and purchasing a gallon of waterproofing sealant and coating your basement walls with it to keep the water out. In our climate with the frost and freeze cycle interior waterproofing is only a temporary solution that can cause bigger issues further down the road that can cause severe structural foundation damage.
Coating a interior wall will still allow the water to enter the foundation, preventing it from exiting into the basement but trapping it inside the wall. Excessive water trapped inside the wall can cause the water to freeze in the winter time and expand, cracking the foundation and allowing more water to enter. Eventually this will erode the concrete beyond repair. Costing thousands of dollars to fix and put your home in a structurally unsafe condition.
Some precautions home owners can take to help prevent water getting into the basement before calling a professional are: adding extended down spouts to keep water away from the house, grading keeping water pitched away from the house and keeping gutters clean. If these do not help call in the pros.
Proper waterproofing of a foundation include: fiber reinforced coating, waterproof membrane, footing drains, cove joint sealing and many more from the exterior.
Attached are a few pictures of a foundation that was beyond repair from severe water issues and we re built.