We built SGP Waterproofing around one idea: a Lewisville, WA property owner 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 Lewisville, WA. 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.
We keep our crews local rather than routing calls through a national call center, which means the technician who answers your questions on the phone is often the same person standing in your basement two hours later. That continuity cuts down on the miscommunication that drags out so many waterproofing jobs.
Freeze-thaw cycles, seasonal rainfall patterns, and water table depth all shift how urgently a given crack or seep needs attention in Lewisville, WA specifically. We track these patterns because they change how we prioritize scheduling during storm season versus a slow drip in the middle of a dry month.
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 Lewisville, WA 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 Lewisville, WA'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.
Drywall that feels soft, bubbles, or shows a tide line near the floor is already absorbing groundwater — by the time you see it, the insulation behind it is usually soaked too.
A window well that fills with water during heavy rain is putting direct pressure on the glass and frame, and it's one of the most common entry points we find in older Lewisville, WA homes.
Water that pools against your foundation after every rain is telling you the drainage system, whatever's left of it, has stopped doing its job.
We scope every Lewisville, WA job in person before quoting it, because two houses with the same symptom rarely need the same fix. These are the five services that make up most of our workload.
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 Lewisville, WA 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.
Parking garages, below-grade retail space, and multi-family basements need waterproofing membranes and drainage systems rated for continuous traffic and higher hydrostatic load.
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 also insulate exposed ductwork inside the crawl space while we're in there, since condensation on cold ducts is a second moisture source people rarely think about.
Sometimes the fix isn't inside the wall at all — regrading the soil away from the foundation and adding a French drain can solve a moisture problem before water ever reaches the block.
You describe what you're seeing and we ask a few questions to gauge urgency before anyone gets in a truck.
A technician maps moisture readings, checks grading, and identifies whether the source is groundwater, surface water, or condensation.
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.
Every quote breaks down materials and labor separately, so you can see exactly what you're paying for instead of one vague lump sum.
Because our crews are based in and around Lewisville, WA, we're not routing your call through a national scheduling system that books you two weeks out.
Our crews run truck-mounted extraction units, moisture meters, and thermal imaging cameras — not a shop-vac and a guess.
If a sealed crack reopens or a sump system underperforms within the warranty window, we come back and make it right at no extra charge.

Warranty terms vary by scope of work, and our technician will walk through exactly what's covered before you sign off on the quote — nothing vague, nothing left to interpretation.


We dispatch crews throughout Lewisville and the surrounding Lewisville, WA 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 Lewisville, WA: 98604

"Our basement flooded during a storm at 2am and someone actually picked up the phone. The crew had pumps running before sunrise and came back two days later to install the drain tile system."
— Lewisville 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."
— Lewisville Seller
"The crawl space under our addition never dried out properly. Full encapsulation with a dehumidifier fixed it in one visit."
— Lewisville Homeowner
"Sump pump failed overnight and flooded part of our storage room. New pump was installed with a backup battery the same afternoon we called."
— Lewisville Customer
"Our parking garage had a persistent leak coming through the deck above the lower level. They installed a membrane system and coordinated the work around tenant parking so nobody was displaced."
— Lewisville 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."
— Lewisville Homeowner
Response time depends on call volume and severity, but emergency water intrusion always jumps the queue ahead of routine estimates.
Yes — every job gets a flat-rate, written quote before work begins, and that number doesn't change once the crew is on-site.
We handle active flooding, sump pump failures, and failed foundation walls with same-day dispatch, portable extraction pumps, and temporary water mitigation.
Pricing varies with scope, but every Lewisville, WA customer gets an itemized written estimate before any work is authorized, so there's never a guessing game.
Hairline cracks are actually the ideal time to call, since injection repair is faster and cheaper before hydrostatic pressure has a chance to widen the gap.
We install both — interior drain tile and sump systems for most residential jobs, and exterior membrane or French drain systems when the source is surface water or when excavation is practical.
Most residential interior drain tile or sump installations finish in one to three days; larger commercial membrane projects can take longer depending on square footage.
Documentation from our inspection often helps speed up the claims process, but final approval is always the insurer's call.
We can walk your specific setup during an inspection and tell you honestly whether your existing drain needs a pump added.
Yes, every interior drainage, sump, and crack repair job comes with a written warranty, and terms are explained in full before you approve the quote.
Standing water doesn't stop us from starting; we extract it as the first step, then proceed with vapor barrier and drainage installation.
Yes — our commercial work covers parking garages, retail basements, and multi-family buildings, usually scheduled in phases to minimize tenant disruption.
One call gets you a licensed technician, a written quote, and a same-day time window.
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