Basement Waterproofing in Ann Arbor, MI

Stop Water at the Source with a Full Exterior Waterproofing System

A wet basement puts your home's foundation, flooring, and indoor air quality at risk. Basement waterproofing keeps groundwater from reaching your basement walls before it becomes a problem inside your home.

Dexter Block provides basement waterproofing in Ann Arbor, MI, for homeowners across Washtenaw County. We build every project around your foundation's specific soil and drainage conditions. So, if your basement floods after every heavy rain, contact us for a free waterproofing inspection.

Signs Your Basement Needs Waterproofing

Water damage in a basement usually doesn't start as a sudden flood. Most homeowners notice water seeping in slowly at first. By the time it's visible on the floor, it has already been getting in for a while.

Watch for these signs:

A musty or earthy smell that cleaning doesn't get rid of.

Damp or discolored walls, especially near the floor.

White, chalky mineral deposits on concrete or block walls, known as efflorescence.

Water on the floor or walls after heavy rain.

Higher indoor humidity or condensation on windows and pipes.

Peeling paint or bubbling drywall near the foundation line.

Why Washtenaw County Basements Are Prone to Water Intrusion

Much of Washtenaw County sits on clay-heavy soil that drains slowly and holds water after rain. When that water can't drain away, it pushes against your foundation walls with nowhere else to go. Homes with crawl spaces face the same pressure. That force, known as hydrostatic pressure, forces water through pores, joints, and small cracks in the wall.

Dexter Block has waterproofed basements across Ann Arbor and Washtenaw County for over 20 years. Owner Kyle Davis learned masonry at his father's company before founding Dexter Block in 2007. That experience makes it easier to spot ongoing hydrostatic pressure early, before it causes lasting water damage.

Our Waterproofing Methods

Water can enter your basement in different ways, so the right fix often combines more than one method. As your local concrete and masonry contractor in Ann Arbor, we offer several waterproofing solutions based on your property's needs. Cracks or a bowing wall signal a different issue, structural damage instead of water intrusion. Our block basement wall repair service fixes cracked or damaged walls. Larger structural concerns fall under our foundation repair service instead.

Exterior Excavation & Waterproofing Membrane

Exterior excavation and membrane application are the waterproofing methods we perform most often. We excavate along the affected foundation wall, then apply a waterproofing membrane and tie the wall into a footing drain system. It's designed to stop water before it reaches the inside of your basement.

Interior Drain Tile Systems

Interior drain tile systems sit inside your basement, along the interior perimeter of the foundation wall. They collect excess water that has already reached the wall and channel it to a collection point, keeping it off the basement floor. This option can pair with our exterior process or stand alone when full excavation isn't practical.

Grading & Downspout Extensions

Grading and downspout extensions help drain water away from your foundation before it becomes a problem. We adjust the slope of the soil around your home, so rainwater flows away from the house. We also extend downspouts far enough that roof runoff doesn't collect against the wall. For yards with a steeper slope, a retaining wall can work alongside grading to manage water flow.

For homes that need more than these three, Dexter Block also installs sump pumps, French drains, and window well drains. These become part of a larger waterproofing plan when needed.

Our Exterior Waterproofing Process

Once we've identified where water is entering, our exterior waterproofing method follows the same process on every job. Here's each step, in order.

1

Consultation & Assessment

We meet with you to go over what's causing concern and what you want the finished basement to look like. This conversation shapes the scope of every step that follows.

2

Excavation

We excavate down to the footing to fully expose the problem wall. This is usually 7 to 8 feet deep and about 4 feet wide.

3

Wall Cleaning & Crack Repair

The exposed wall is power washed, then any cracks are filled with mortar before waterproofing begins.

4

Membrane & Insulation Application

We apply Mel-Rol, a bituminous waterproofing membrane, directly to the wall below grade. A 2-inch EPS foam board goes over the membrane to protect it during backfill.

5

Drain Tile Installation

A 4-inch perforated sock tile, a drainpipe wrapped in fabric that filters out soil, is installed along the footing. It ties into your home's existing drain tile system, giving water a clear path away from the wall. This footing drain is different from the standalone interior drain tile option described earlier. It works together with the membrane as part of the same exterior system.

6

Backfill & Final Grading

We backfill with pea stone to within 18 inches of grade, then finish with the original soil and topsoil. The last step is grading the surface, so water runs away from the wall.

Backed by a 7-Year Warranty and Michigan Licensing

Every exterior waterproofing project comes with a 7-year warranty. It covers labor and materials against future basement leaks, so a wall we've waterproofed stays covered long after the crew leaves.

However, that coverage would mean little without a contractor who is properly licensed and insured to back it up. Dexter Block carries liability and workers' compensation insurance on every project.

Basement Waterproofing Across Washtenaw County

Dexter Block waterproofs basements throughout Ann Arbor and the surrounding Washtenaw County area, including Dexter and Saline.

If you're unsure whether your address falls within our service area, contact us and we'll confirm before scheduling an inspection.

Basement Waterproofing FAQs

FAQ

A single wall usually takes 4 to 5 days to complete. Larger jobs covering multiple walls take longer, depending on the scope. Weather also plays a role, since excavation is more difficult once the ground freezes. We'll walk you through an estimated timeline during your free inspection.

Yes. The City of Ann Arbor requires a building permit for this type of work. Permits help confirm the excavation and waterproofing meet local safety and code requirements. Ask your contractor whether they handle the permit application or if that falls to you as the homeowner.

Most standard homeowners policies don't cover waterproofing as routine maintenance. Coverage sometimes applies if the damage comes from a sudden, covered event. It's worth checking directly with your insurance provider.

Waterproofing addresses water and moisture entering your basement. Wall repair addresses structural damage like cracks or bowing walls, covered by our basement wall repair service. If you're seeing both issues, we can evaluate what your home needs.

Cost depends on the scope of work, how many walls need attention, and which methods your property needs. We provide a detailed quote after a free, in-person inspection.

Ready to Waterproof Your Basement?

Basement issues rarely wait for a convenient time. Every day water keeps reaching your foundation is a day closer to mold, a costlier repair, or lasting structural damage. So, schedule your free inspection now, before the next heavy rain makes the problem worse.

Call 734-424-9420 or request your free inspection below.