Hear from Our Customers
You stop worrying every time it rains. That’s the difference between a quick fix and doing it right the first time.
When your basement is properly waterproofed, you’re not dealing with musty smells anymore. You’re not watching the weather forecast with anxiety. You’re not calling emergency services at 11 PM because water’s coming through the floor again.
Your home value stays protected. Your family’s health isn’t compromised by mold growth. And you can actually use that space without wondering if everything down there is going to get ruined.
Chester County’s clay-rich soil creates real hydrostatic pressure against your foundation walls. When heavy rain hits, that pressure doesn’t just disappear. It needs somewhere to go, and if your waterproofing system isn’t designed to handle it, it’s coming through your basement.
A proper waterproofing system in Exton, PA means you’ve got drainage working with the water, not against it. The pressure gets relieved before it becomes your problem. That’s what keeps basements dry for decades, not just seasons.
Del Val Basement Waterproofing is a family-owned waterproofing contractor serving Exton, PA and the broader Chester County area. John Harte started this company specifically because too many homeowners were getting hit with outrageous estimates for work that shouldn’t cost that much.
We’ve completed thousands of waterproofing installations across the Delaware Valley. Our focus is on Sub Floor Pressure Relief Systems—the kind structural engineers actually recommend—not outdated methods that only work temporarily.
Exton homeowners deal with specific challenges. The development boom here means more parking lots, more runoff, and more water ending up where it shouldn’t. We understand how local soil conditions and drainage patterns affect your property, and we design systems accordingly.
Every job comes with a lifetime transferable warranty. That’s not marketing language—it’s how confident we are that the work will last.
First, we come out and actually look at what’s going on. Not every wet basement needs the same solution, and we’re not going to sell you something you don’t need.
We identify where the water’s coming from—whether it’s hydrostatic pressure, surface water, foundation cracks, or a combination. We check your grading, your drainage, and how water moves around your property during heavy rain.
Then we explain what needs to happen and why. If you need interior waterproofing with a Sub Floor Pressure Relief System, we walk you through how it works: we install drainage channels along the foundation footer, connect them to a sump pump system, and create a path for water to exit before it ever reaches your basement floor.
For exterior work, we excavate around the foundation, apply waterproof membrane, install proper drainage systems, and make sure water gets directed away from your home. Sometimes you need both interior and exterior solutions. Sometimes you don’t.
We give you a written estimate with no pressure to sign immediately. If you move forward, we schedule the work, complete it efficiently, and clean up like we were never there—except your basement stays dry.
The warranty paperwork gets filed, and you’ve got our number if anything ever comes up. Most of the time, it doesn’t.
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You get a complete waterproofing system designed for Exton, PA conditions—not a generic solution that works somewhere else but fails here.
That includes interior drainage systems that handle the hydrostatic pressure from Chester County’s clay soils. We install perimeter drainage channels, high-capacity sump pumps with battery backup, and proper discharge lines that move water away from your foundation. If your crawl space needs encapsulation, we seal it completely and install dehumidifiers to control moisture year-round.
For foundation issues, we handle crack repair using methods that actually hold—not surface patches that fail in six months. If you’ve got bowing walls or structural concerns, we address those with carbon fiber reinforcement or wall anchors, depending on what the situation calls for.
Exton’s flooding challenges are real. Chester County has over 2,300 miles of streams and more than 250 known flooding locations. Your property might not be in a floodplain, but increased development means more stormwater runoff hitting residential areas. Our systems are designed knowing that water volume isn’t decreasing—it’s getting worse.
You also get mold remediation if needed. We don’t just cover up the problem. We remove contaminated materials safely, treat affected areas, and restore healthy air quality before we waterproof.
Everything comes with that lifetime transferable warranty, which means if you sell your home, the protection transfers to the next owner. That’s a selling point most basements don’t have.
Most basement waterproofing projects in Exton, PA run between $3,000 and $10,000, depending on the size of your basement, the severity of the water problem, and whether you need interior systems, exterior work, or both.
A straightforward interior perimeter drain system with a sump pump typically falls on the lower end. If you’ve got foundation cracks that need repair, exterior excavation and waterproofing, or crawl space encapsulation added to the scope, costs go up from there.
Here’s what affects price: the linear footage of your foundation, how much excavation is required, whether we’re working with finished or unfinished space, and what kind of drainage solutions your property needs. A 1,000-square-foot basement with minor seepage needs different work than a 2,000-square-foot space with standing water after every storm.
We give free estimates with no pressure, and we explain exactly what you’re paying for. You’re not getting an inflated number because we think you’ll negotiate down. You’re getting the actual cost to fix the problem correctly, and that includes our lifetime warranty.
Heavy rain creates hydrostatic pressure in the soil around your foundation. Chester County has clay-rich soil that doesn’t drain quickly, so water sits against your foundation walls and floor, building pressure until it finds a way inside.
That water comes through foundation cracks, the joint where your floor meets the wall (called the cove joint), or directly through porous concrete. Even small cracks become major entry points when you’ve got sustained pressure from saturated soil.
Exton’s development patterns make this worse. More pavement and buildings mean less ground to absorb rainfall, so water runs off into areas it didn’t used to reach—including around your home’s foundation. If your gutters aren’t directing water far enough away, or if your yard slopes toward your house instead of away from it, you’re compounding the problem.
A proper waterproofing system relieves that pressure before water enters your basement. Interior drainage channels collect water at the footer level and direct it to a sump pump, which removes it from your property. Exterior waterproofing creates a barrier and drainage path so water never builds up against your foundation in the first place.
Interior waterproofing manages water after it’s entered the foundation structure but before it reaches your basement floor. We install drainage channels along the perimeter at the footer level, which collect water and direct it to a sump pump system. This relieves hydrostatic pressure and keeps your basement dry without excavating your yard.
Exterior waterproofing stops water before it reaches your foundation walls. We excavate around the outside of your home, apply waterproof membrane to the foundation, install drainage systems, and regrade if necessary. This method creates a complete barrier, but it’s more invasive and typically costs more.
Which one you need depends on your specific situation. Interior systems work extremely well for most homes in Exton, PA and they’re less disruptive to install. If you’ve got significant foundation damage, exterior work might be necessary to address structural issues while waterproofing.
Sometimes the best solution is both—exterior waterproofing where you’ve got foundation problems, and interior drainage to handle any water that still makes it through. We assess your property and recommend what actually makes sense for your situation and budget, not what makes us the most money.
A properly installed waterproofing system should last the lifetime of your home. That’s why we back our work with a lifetime transferable warranty—we’re installing systems designed to perform for decades, not just a few years.
The key is using the right materials and methods for Chester County conditions. Sub Floor Pressure Relief Systems, which we specialize in, are built to handle the ongoing hydrostatic pressure from our clay soils and heavy rainfall patterns. These aren’t temporary fixes that fail when conditions get tough.
Your sump pump will need eventual replacement—most last 7-10 years depending on how often they run. We install high-quality pumps with battery backup systems so you’re protected even during power outages. The drainage channels, waterproof membranes, and structural components last much longer when installed correctly.
Regular maintenance helps. That means testing your sump pump a couple times a year, keeping discharge lines clear, and making sure your gutters are directing water away from your foundation. But the core waterproofing system itself shouldn’t need replacement if it’s done right the first time.
We’ve seen plenty of homes where waterproofing failed after just a few years—usually because it was installed incorrectly or used outdated methods. That’s not how we work, and it’s not what you’re paying for.
Waterproofing and foundation repair often go hand-in-hand, but they’re not the same thing. If you’ve got foundation cracks, we need to repair those first before waterproofing—otherwise, you’re just sealing in a structural problem.
For minor cracks, we use injection methods that fill the crack completely and create a waterproof seal. For more serious foundation issues like bowing walls or significant settling, we use carbon fiber reinforcement or wall anchor systems to stabilize the structure before we waterproof.
Water is usually what causes foundation problems in the first place. Hydrostatic pressure from saturated soil pushes against foundation walls, creating cracks and bowing. Expansive clay soils in Exton, PA make this worse—the soil expands when wet and contracts when dry, creating constant pressure changes that stress your foundation.
Once we’ve addressed the structural repairs, waterproofing prevents future damage. The drainage systems we install relieve that hydrostatic pressure so your foundation isn’t constantly fighting against water buildup. That’s how you stop the cycle of ongoing foundation damage.
If you’re seeing new cracks, horizontal cracks, or walls that are bowing inward, get that looked at quickly. Foundation problems don’t improve on their own, and waiting makes repairs more expensive. We’ll assess what’s happening structurally and recommend the right combination of foundation repair and waterproofing to fix it permanently.
Small surface moisture issues—like condensation from humidity—you can sometimes handle with a dehumidifier and better ventilation. But if you’ve got water coming through your walls or floor, especially after heavy rain, that’s not a DIY situation.
Basement waterproofing requires understanding how water moves through soil, how hydrostatic pressure works, and how to design drainage systems that actually relieve that pressure. Installing interior drainage means breaking up your basement floor along the perimeter, excavating down to the footer, installing proper drainage channels with the right slope, connecting to a sump system, and then restoring the floor. If any part of that is done incorrectly, you’ve just spent money and effort on something that won’t work.
Exterior waterproofing is even more complex. You’re excavating around your foundation, which requires knowing how deep to go, what waterproof membranes to use, how to install drainage without damaging your foundation, and how to backfill properly. Do it wrong and you can actually make your foundation problems worse.
The bigger issue is diagnosis. What looks like a simple leak might be a symptom of foundation settling, inadequate drainage, or failing waterproofing from previous work. A residential waterproofing company in Exton, PA knows how to identify the actual source and fix it correctly the first time.
You’re also not getting a warranty on DIY work. If our system fails, we come back and fix it at no cost. If your DIY attempt fails, you’re paying twice—once for materials and your time, and again to have it done properly.
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