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Waterproofing Dearborn's brick and block basements
Updated October 19, 2026 · referral service, not a contractor
Half of Dearborn's houses were built before 1950, and most of those have brick or early concrete-block foundations with clay drain tile. Waterproofing them means three things in order: get the water that's already there to a sump that discharges outside, stop the wall from passing water, and keep the public sewer out of the basement.
Interior drain tile and sump
A contractor cuts a channel along the base of the wall, lays perforated pipe in stone next to the footing, and runs it to a new sump pit. For brick walls, a drainage membrane goes up the wall so water weeping through old mortar drops into the channel instead of onto the floor; for block, weep holes are drilled in the bottom course. Dearborn's compact 1920s–40s basements (often 700–900 square feet) make full-perimeter systems more affordable than in newer suburbs.
Wall work on brick foundations
Erosion of lime mortar is the usual failure in pre-1940 brick. Repointing from inside, then a parge coat, then the membrane. Where the brick has spalled badly or the wall has shifted, the contractor may recommend exterior excavation to apply a membrane from outside; on Dearborn's narrow side yards (many under ten feet between houses) that's done in sections, by hand.
Keeping the sewer out
This is the part specific to Dearborn. The city states its sewer system was designed for three inches of rain in 24 hours and that roughly 5.8 inches fell in the 2014 storm and 7.5 inches in June 2021. If your footing drains and floor drain connect to that system, waterproofing the walls doesn't help on the night it surcharges. A backwater valve on the sanitary lateral, footing drains rerouted to a sump that pumps outside, and a sealed floor drain are the pieces; see the sump and backwater page.
Outside the house
Downspouts on these houses often still drain into the ground (and into the sewer). Disconnecting them to splash blocks or extensions that run water away from the foundation is the cheapest flood-reduction step in Dearborn, and the city's own flood guidance encourages it. Regrading settled soil along the foundation is the second.
At the estimate
- Which problem you have: backup, seepage, or both.
- Wall material and condition, drain tile condition, where the floor drain goes.
- Linear feet, pump and backup models, backwater valve included or not, warranty, and who pulls the Dearborn plumbing permit.
Ask for a free estimate
Tell us what happened in the basement. One independent contractor who works in Dearborn calls you to arrange a free visit and a written estimate. The referral is free; you never pay us.
Sources
- U.S. Census Bureau, ACS 2024 1-year estimates, tables B25034, B25035, B25003, Dearborn city, MI (via Census Reporter API) — https://censusreporter.org/profiles/16000US2621000-dearborn-mi/
- City of Dearborn, Flood Preparedness & Recovery (sewer system designed for 3 inches in 24 hours; ~5.8 inches in 2014 and ~7.5 inches in 2021; northeast and southeast sections most impacted in June 2021; CDBG-DR projects) — https://dearborn.gov/residents/flood-preparedness-%26-recovery
- HomeGuide, basement waterproofing cost (national averages) — https://homeguide.com/costs/basement-waterproofing-cost