Key Waterproofing Construction

When a homeowner's sump pump failed this February, Key Waterproofing Construction was at the house within the hour — a $1,400 call answered on the spot, and a fair picture of how this company gets used. Key is a Holbrook, Massachusetts basement waterproofing outfit. It says it has twelve years behind it and covers eastern Massachusetts and southern New Hampshire, including the North Shore, South Shore and Cape Cod. The volume is what stands out: 4.7 stars across 197 reviews, 89 percent of them five-star, running back to 2024. The praise settles on the same handful of things — crews described as hardworking and professional, a clean worksite when they finish, prices customers found fair, and someone taking the time to walk through the process before work starts. Both Angi and HomeAdvisor list the company as Approved, a badge tied to holding a 4.5-star-or-better average. Two things to weigh. Those 197 reviews all live on Angi and HomeAdvisor, which publish the same set, so the picture comes from one directory family rather than several independent places. And roughly two percent of the ratings are one-star with another one percent at two — a small share of 197, but worth asking what went wrong on those jobs. Both sites also list a Massachusetts trade registration, number 217612, with a stated expiry of December 4, 2027. That is the company's own listing rather than a state registry record, so check it yourself before signing. For a wet basement or a failing sump system in eastern Massachusetts, Key has more reviewed history behind it than most in the trade and a record of moving fast. Confirm the registration, and get the scope and any warranty in writing when you take the quote.