Basement Waterproofing & Crawl Space Repair in Greater Philadelphia Jamison Basement Waterproofing is a family-owned and operated, award-winning home services company, helping Philadelphia, Southern NJ & Delaware homeowners for over 30 years. The Jamison Basement Waterproofing team of caring employees offer affordable basement and crawlspace waterproofing solutions with a transferable, Life of Structure Warranty…and, it’s nationally backed by the Grate Products Contractor Network. We care about the health of our customers, and offer a “Healthy Basement Certificate“ ensuring that their homes are protected from the ill-effects of high humidity, moisture & mold.