Contractors cut a trench in the basement floor to install a perimeter drain and sump pump.

Like most older homes in our area, ours suffers from water intrusion in heavy rain, with water running across the floor to a sump previous owners had installed. It was tolerable, if annoying, when we used the basement for laundry, storage, and shop space, but it was a problem we needed to solve if we were going to renovate with an eye to adding living space. I briefly considered installing a perimeter drain myself following the instructions on familyhandyman.com, but the thought of moving tons of earth and concrete didn’t appeal. After reviewing bids from a couple of local companies, we selected PermaDry Waterproofing. While they were slightly higher than other bids, I appreciated their materials choice (perforated PVC over corrugated polyethylene) and design. After some government-shutdown-induced rescheduling, PermaDry brought in two crews to install an interior perimeter drain and sump pump in a single day.

Installation requires breaking through basement slab around the foundation to cut a trench. Perforated PVC is buried in gravel and buried in geotextile and (optional) dimple matt is installed along the wall below ground level so that any water hitting the foundation walls hits the mat and runs into the drain.  Once the drain and sump are installed, new concrete is poured. Since my attempts at concrete work are extremely rough (not a problem for my usual fence footings) I was particularly impressed by the smooth finish on the new concrete. The PermDry team was on time, did good work to plan at a competitive price, so I can recommend them to potential customers in Puget Sound.