We built SGP Waterproofing around one idea: a homeowner or property manager in Sandusky, MI shouldn't have to wait three days for someone to look at a wet wall.

SGP Waterproofing is a licensed and insured Waterproofing contractor serving homeowners, property managers, and commercial building owners across Sandusky, MI. We didn't start as a marketing company that added waterproofing to a service list — our crews came up running sump pumps, pouring interior drain tile, and injecting epoxy into foundation cracks long before the trucks had our name on the door.
Because we staff locally instead of subcontracting out to whoever's available, the estimate you get over the phone tends to match the invoice you get at the end of the job — no surprise line items, no upsell script.
Soil composition changes how much hydrostatic pressure builds against a foundation wall, and Sandusky, MI's mix of clay-heavy and sandy soils behaves differently depending on the neighborhood, sometimes block to block. A crew that hasn't worked the area tends to size drainage systems using generic assumptions instead of what's actually under the yard.
We also see a lot of properties where a previous waterproofing attempt only addressed the symptom — a topical sealant painted over a cracked wall, for example — without solving the pressure or grading issue causing the crack in the first place. Part of every Sandusky, MI inspection is checking for that kind of prior patch job before we recommend anything new.

Water damage rarely announces itself with a flooded basement on day one. It usually shows up as one of these smaller signals first, and Sandusky, MI's seasonal moisture swings tend to speed the timeline up.
A persistent musty smell almost always means moisture is present somewhere in the wall assembly, even if you can't see a wet spot yet.
Efflorescence forms when water carries dissolved minerals through porous concrete and leaves them on the surface as it dries — a clear sign moisture is actively passing through.
A crack that's a sixteenth of an inch wide today can become a sixteenth of an inch wider by next spring if the pressure behind the wall isn't relieved.
Bubbling paint or soft drywall near the baseboards is one of the last signs to show up, which means moisture has typically been present for weeks already.
If your window wells hold water for more than an hour after a storm, that water has nowhere to go but toward the seal around your basement window.
Puddling near the foundation that doesn't drain within a few hours usually means grading, gutters, or a failing perimeter drain — and it's the fastest path to a flooded basement.
Every job starts with the same on-site inspection, whether it's a single crack or a full interior drainage retrofit. Below are the services Sandusky, MI clients request most often.
A burst window well seal or a failed check valve can put inches of water in a basement in under an hour — our emergency crews carry truck-mounted extraction pumps and moisture meters to start mitigation the same day you call.
Most Sandusky, MI basements need a combination of interior drainage and a properly sized sump pump — we size the system to your square footage and soil type, not a one-size-fits-all package.
Commercial jobs typically pair exterior membrane work with an interior collection system, since most existing commercial structures can't be fully excavated without major disruption.
If a wall is bowing rather than just cracked, we'll flag that during the inspection since injection alone won't address a structural deflection issue.
We install heavy-gauge vapor barriers, seal foundation vents, and add a dedicated sump basin so a damp Sandusky, MI crawl space stops feeding moisture into the floor joists above it.
We trace surface water back to its source, which is often a downspout discharging too close to the foundation or a grade that slopes the wrong direction entirely.
A dispatcher walks through symptoms with you on the phone so the crew that shows up already has a rough idea what they're dealing with.
We walk the interior and exterior with a moisture meter and flashlight, tracing water back to its actual entry point instead of guessing.
We put the scope, materials, and price in writing so you can compare it against anyone else's estimate line for line.
Most residential jobs finish in one to three days, and we walk the property with you afterward to confirm every drain, pump, and seal is working.
You'll know the total cost before we start — no hourly billing, no surprise add-ons once the walls are already open.
Local staffing means the technician answering your call today can usually be on-site the same day, not on a waitlist behind out-of-town jobs.
We also carry Category 1, 2, and 3 water classification protocols for jobs where the source water isn't clean groundwater.
Warranty callbacks get the same dispatch priority as a new emergency, because a repeat leak is still an active problem for you.

Every interior drainage system, sump installation, and crack repair we complete in Sandusky, MI comes with a written, transferable warranty — useful if you sell the property before the coverage period ends.


We dispatch crews throughout Sandusky and the surrounding Sandusky, MI service area, including the zip codes listed below. If you're just outside the boundary, call anyway — we often still make the trip.

Zip codes we serve in Sandusky, MI: 48471

"We had water coming in around the window well every time it rained hard. They regraded the area and sealed the well, and we haven't had a drop since."
— Sandusky Homeowner
"The crack in our basement wall had been leaking for a year before we finally called. Injection took less than an afternoon and it's been dry since."
— Sandusky Seller
"Our crawl space had standing water and a mold smell we couldn't get rid of. They pumped it out, encapsulated the whole thing, and added a dedicated sump discharge line."
— Sandusky Homeowner
"Our old sump pump died during the biggest storm of the year and we got water in the finished basement. They replaced it with a battery backup system so we're covered even during a power outage."
— Sandusky Customer
"Property management hired them to fix water coming through the garage ceiling. They scheduled the membrane work in phases so we never had to close the whole garage."
— Sandusky Property Manager
"They found the actual source of the dampness instead of just recommending a dehumidifier and calling it done. Been dry for over a year now."
— Sandusky Homeowner
For active flooding we prioritize same-day dispatch across our Sandusky, MI coverage area; routine inspections usually book within 48 hours.
We quote the full scope in writing after the inspection, so there's no hourly billing or surprise change orders once installation starts.
Our emergency response covers water extraction, temporary pump-outs, and emergency crack sealing to stop active intrusion until permanent repairs are scheduled.
We avoid quoting ballpark numbers over the phone because two basements with the same symptom can need very different fixes.
We repair cracks of nearly any size — hairline cracks are often the easiest and least expensive to seal with polyurethane or epoxy injection before they widen.
The right system depends on access, budget, and what's actually driving the water in — we'll explain the trade-offs before you decide.
We give you a realistic timeline in the written quote so you can plan around the crew being on-site.
We're happy to provide the documentation adjusters typically request, though we recommend confirming your specific coverage details directly with your insurance provider.
In most cases yes — a French drain collects water, but it still needs a sump pump to actually move that water out and away from the foundation.
We back our work with a written, often transferable warranty — useful if you sell the property before the coverage period runs out.
Standing water doesn't stop us from starting; we extract it as the first step, then proceed with vapor barrier and drainage installation.
Commercial scheduling is handled separately from residential dispatch so larger projects get the coordinated planning they need.
One call gets you a licensed technician, a written quote, and a same-day time window.
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