Exterior Basement Waterproofing
Help Stop Water on the Outside of the Wall. Before It Reaches Your Basement.
WetSuit is a spray-applied rubberized waterproofing membrane. We excavate along the outside of your basement wall, seal the surface with a seamless coating and manage water away from the foundation. The work happens outside, with no concrete breakout inside your home.
Watch how Olshan seals a basement wall from the outside with WetSuit.
What Is WetSuit Exterior Waterproofing?
Many basement leaks start where water sits against the outside of the wall. Soil holds moisture, hydrostatic pressure builds, and water works through cracks, mortar joints and the cold joint where the wall meets the footer. WetSuit is applied at that point, on the outside, to help keep water off the wall rather than collecting it after it is already inside.
WetSuit is a water-based, cold spray-applied rubber membrane. Our crew excavates the soil along the affected wall, cleans and preps the concrete or block, then sprays the membrane directly onto the wall. It sets quickly into a continuous rubber layer that bonds to the surface and is designed to flex with the wall as soils move through wet and dry seasons. Because it is sprayed rather than laid out in sheets, there are no seams, laps or fastener holes for water to find.
- Seamless membrane with no laps or joints
- Bonds directly to poured concrete and masonry block
- Stays flexible after cure to move with the wall
- Water-based and coal tar free, applied cold with no torches
- Installed with drainage that helps move water away from the foundation
How the WetSuit Process Works
Four steps, all performed outside your home.
1
Excavate the Wall
We dig along the exterior of the affected basement wall down to the footer to expose the surface that needs protection.
2
Prep the Surface
The wall is cleaned of soil and loose material. Cracks, joints and the wall-to-footer transition are detailed so the membrane covers the common entry points.
3
Spray Apply WetSuit
The membrane is sprayed on in a continuous pass and sets quickly, forming a seamless rubber barrier bonded to the wall.
4
Drain and Backfill
Footer drainage is added where the site calls for it, the membrane is protected, and the excavation is backfilled and graded to help shed water away from the home.
Why Homeowners Consider WetSuit
A strong fit for finished basements, occupied homes and walls with several entry points. Not every home needs it, and your Certified Structural Technician will tell you if it is not the right call.
Work Stays Outside
Interior drainage systems require opening the basement floor along the wall. WetSuit keeps the dust, noise and concrete work outside the home.
Finished Space Stays Put
Drywall, flooring, built-ins and stored belongings can stay in place. Nothing inside has to come out to reach the wall.
Addresses Water at the Wall
The membrane helps keep water from contacting the wall in the first place, which also helps the wall itself stay drier over time.
Seamless Coverage
Sheet membranes rely on overlaps and adhesive at every edge. A spray-applied membrane has none, so there are fewer weak points for water to find.
Pairs with Structural Repair
If a wall is already excavated for straightening or footer work, sealing it at the same time is efficient and helps protect the repair.
Backed Two Ways
An available Olshan warranty on the installation, plus the manufacturer’s warranty on the WetSuit product itself. Ask your Certified Structural Technician for details.
Interior and Exterior Waterproofing: Two Approaches, Often One Plan
Both are proven methods we install every day. They solve the problem from different sides of the wall, and many homes benefit from a combination.
| Interior Waterproofing | Exterior Waterproofing with WetSuit | |
|---|---|---|
| Where the work happens | Inside the basement | Outside the home |
| How water is handled | Water that enters is collected below the floor and discharged away from the home | Water is intercepted at the outside of the wall and directed to exterior drainage |
| Interior disruption | Concrete along the wall is opened and restored; finishes along that wall are removed | None inside; landscaping in the work area is disturbed and restored |
| Sump pump | Typically part of the system | Sometimes recommended depending on water table and site drainage |
| Install time | Generally shorter | Generally longer, depends on excavation |
| Serviceability | Easy to access and service | Serviceable; buried membrane is protected from sun and weather |
| Often the better fit when | The basement is unfinished, the slab is monolithic, exterior access is limited, or water enters at the floor | The basement is finished or occupied, water enters through the wall, and the exterior is accessible |
No waterproofing method can promise a basement will never see moisture again. Soil, weather and water tables change, and mother nature is tough to beat. The goal is to reduce the ways water gets in and manage what remains. That is why your Certified Structural Technician evaluates the whole picture before recommending one method, the other, or both.
Is WetSuit the Solution for Your Wet Basement?
Where the water comes in decides the fix. This video walks through when WetSuit is the right call, when another approach fits better, and how it works alongside the rest of your water management plan.
When to choose WetSuit, and how it pairs with drainage, sump pumps and interior systems.
Build a Complete Water Management Plan
WetSuit is one tool in the kit. Open an option below to see how it works alongside the other Olshan services that may be part of your plan.
Exterior DrainageUsually installed together
Footer Drain, Gravel Fill and Exterior Drainage
With the wall already excavated, a footer drain with gravel fill is the natural companion to WetSuit. The membrane helps keep water off the wall; the drain gives water that reaches the footer somewhere to go, which helps relieve hydrostatic pressure at the base of the wall.
Water Lock PlusComplementary system
Water Lock Plus Interior Drainage
Our most powerful interior discharge system collects water at the footer from inside the basement and moves it to a discharge point. Some homes get the best result from an exterior membrane on the worst wall plus Water Lock Plus along the rest of the perimeter. It is not either-or.
Sump PumpsRecommended when needed
Sump Pumps and Gravity Discharge
Exterior waterproofing is designed to keep water out rather than pump it out, so a sump pump is not always required. When the water table is high or drainage cannot exit by gravity, a sump basin, pump and battery backup add a reliable safety net.
Wall Shield LinerAdded interior defense
Wall Shield Interior Moisture Barrier
Wall Shield is a liner installed on the inside face of the basement wall that directs seepage and condensation down into an interior drainage system. Paired with WetSuit on the outside, it adds a second layer of moisture control from the inside.
Wall StabilizationStructural first
Bowed or Tilted Wall Stabilization
Water pressure and expansive soils can push basement walls inward. If your wall is bowing, cracking or tilting, stabilizing it comes first. Since the wall is often excavated for that work, applying WetSuit at the same time is efficient and helps protect the repaired wall going forward.
Surface Water ControlLow cost, high impact
Surface Drains, Downspout Extensions and Grading
Much of the water that ends up against a basement wall starts at the roof and the surface. Extending downspouts, adding surface drains and regrading so the yard slopes away from the home reduce the load on every other system, including WetSuit.
Warranty Coverage
Two layers of protection behind every WetSuit installation.
Available Olshan Installation Warranty
Ask your Certified Structural Technician about the warranty program available with WetSuit exterior waterproofing. Terms and coverage are reviewed with you before work begins so there are no surprises.
Manufacturer’s Product Warranty
The WetSuit membrane itself is warrantied by the manufacturer. Combined with the Olshan installation warranty, you are covered on both the product and the workmanship.
Installed by Olshan Certified Structural Technicians
Every WetSuit project starts with a free evaluation. Your Certified Structural Technician identifies where water is entering, checks the wall for structural concerns, reviews drainage around the home and builds a plan that fits your goals and budget. If WetSuit is not the right solution for your home, we will tell you and show you what is. Convenient payment plans are available.
WetSuit Exterior Waterproofing FAQ
Is WetSuit the same as tar or foundation coating?
No. Traditional damp proofing is a thin coating meant to slow moisture rather than resist water under pressure. WetSuit is a true waterproofing membrane, a water-based rubber that cures into a thick, flexible, seamless layer designed to help keep water off the wall.
Will you have to dig up my whole yard?
Only the wall or walls that are letting water in are excavated. Landscaping in the work area is disturbed, but the interior of your home is not. Once the membrane and drainage are in place, the trench is backfilled and graded.
Do I still need a sump pump?
Sometimes. Exterior waterproofing is designed to keep water out rather than pump it out, so many homes do not need one. If the water table is high or drainage cannot be routed away by gravity, your Certified Structural Technician may recommend a sump system as part of the plan.
Can WetSuit be applied to block walls?
Yes. WetSuit bonds to both poured concrete and masonry block. Mortar joints and cracks are detailed first so the membrane covers the common paths water takes.
Will my basement be completely dry afterward?
WetSuit is designed to help stop water at the outside of the wall, and in combination with drainage it significantly reduces the ways water can get in. No method can guarantee against every storm, soil change or rising water table. That is why we design the whole system around your home rather than relying on one product.
Is this better than interior waterproofing?
It is different, not better. Interior systems like Water Lock Plus manage water that enters. Exterior waterproofing with WetSuit helps keep water from reaching the wall. Each has situations where it is the stronger choice, and many homes use both. Your Certified Structural Technician will recommend what fits your home.
Is the product warrantied?
Yes. The WetSuit membrane carries a manufacturer’s product warranty, and Olshan offers an available installation warranty. Both are reviewed with you at your evaluation.
Keep Your Basement Drier Without Tearing It Apart
Schedule a free, no-obligation evaluation. An Olshan Certified Structural Technician will find where the water is coming from and show you the options for managing it.
Or call 877-4-OLSHAN to reach the office nearest you.