Licensed & Insured Independent Pros
You'll be connected with insured, independent contractors, many of whom work with builders and general contractors.
From new-construction membranes to retrofits on older Bethesda homes, one call connects you with a licensed, insured independent pro who keeps water out of the foundation itself.

Here's something most homeowners never hear: the black coating sprayed on most new foundations is damp-proofing, not waterproofing. Damp-proofing slows vapor. It doesn't bridge cracks, and it breaks down over time in wet soil. Once the soil around the house saturates, water pushes through shrinkage cracks, tie-rod holes, form joints and pipe penetrations.
Block foundations add another weak point. The mortar joints and hollow cores soak up moisture, which shows up as white efflorescence, peeling paint and a constant damp feel. Proper foundation waterproofing turns the wall into a real barrier with membranes and drainage built for water pressure.
For new homes, it's far cheaper to do it right before backfill. For existing homes, contractors can excavate and retrofit, or combine targeted exterior work with interior drainage.

Not every foundation faces the same water. A house on sandy, well-drained soil with a low water table needs good protection and a working footing drain, but it isn't fighting constant pressure. A house on dense clay, a low lot or a site with a seasonal high water table has water sitting against the wall for weeks. That second house needs a heavier membrane, a drainage board with real flow capacity and a footing drain that can keep up.
Fluid-applied membranes are the most common choice for residential work. They go on seamless, wrap around tie-rods and penetrations, and bridge hairline cracks. The key quality check is thickness: the crew should measure wet film thickness as they go, because a membrane applied too thin won't perform as rated.
Commercial foundations and tough sites often get sheets or bentonite. Sheets give a consistent factory thickness, which helps on large wall areas. Bentonite swells when it gets wet and seals small gaps on its own, though it needs to be confined by backfill to work properly.
Membrane and drainage work as a pair. Drainage board and a footing drain take the pressure off, so the membrane only has to deal with water that's already moving away. Skipping drainage to save money is one of the most common reasons foundation waterproofing fails early.
Cost depends mostly on access and depth. On new construction, with the walls already exposed, you're paying for materials and application. On an existing home, excavation, hauling, shoring for deep trenches and restoring landscaping usually make up the larger share of the bill. A contractor should break those pieces out separately so you can see where the money goes, and so you can compare a full-perimeter job against sealing only the walls that actually leak.

Getting the materials and the prep right is what makes it last.
You'll be connected with insured, independent contractors, many of whom work with builders and general contractors.
Pricing is written by wall section or linear foot, with membrane type, drainage board and footing drain called out separately.
Builders on a schedule and homeowners with active seepage both get quick scheduling from contractors who work in Bethesda.
Airless spray rigs for fluid-applied membranes, wet film thickness gauges, pressure-wash surface prep and low-pressure injection kits for penetrations.
A complete job layers protection so water has no easy path through.

A thick, seamless rubberized asphalt or polymer membrane is sprayed or rolled onto the cleaned wall at a specified mil thickness. It stretches to bridge small cracks that would split ordinary damp-proofing.
Peel-and-stick sheets offer uniform thickness, while bentonite swells on contact with water to self-seal. Both suit tough sites.
A dimpled drainage board over the membrane protects it from rocks during backfill and gives water a free path down to the footing drain, relieving pressure on the wall.
A gravel-bedded, filter-wrapped drain at the footing carries water away so the membrane isn't holding back a saturated trench.
Tie-rod holes, pipe sleeves and conduit entries are the most common leak points in poured walls. Contractors seal them with hydraulic cement, polyurethane injection or flexible sealant collars.
A cement parge coat fills block joints and gives the membrane a solid, smooth surface to bond to.
Most foundation waterproofing failures trace back to a handful of shortcuts. The first is skipping surface prep. A membrane applied over dirt, loose parging or form release oil won't bond, and water gets behind it within a few seasons. The second is applying it too thin. Fluid membranes are rated at a specific thickness, and a crew in a hurry can easily put on half that.
The third is leaving out the drainage board, which lets sharp backfill puncture the membrane and leaves water pressing against the wall instead of draining down. The fourth is a footing drain with no outlet, or one that discharges into a spot that floods. The last is backfilling with the same clay that came out of the hole, which holds water against the wall. A contractor who explains how they avoid each of these is one who has seen what happens when they're ignored.
On an existing home, ask the contractor how they'll protect the membrane during backfill, where the footing drain will discharge and how the final grade will slope. Those three answers tell you more about the quality of the job than the brand name on the membrane bucket.
Here's the sequence from the first call to backfill.
Call +1-866-476-1348 and describe the foundation type, the moisture and your timeline.
A nearby contractor confirms a visit, working around construction schedules when needed.
Expect a wall inspection, a system recommendation suited to the site and an itemized written quote.
The wall is prepped and sealed, drainage board and footing drain go in, and the contractor documents the work before backfill and reviews the warranty with you.
Call now for a free referral to a licensed, insured independent foundation waterproofing contractor in Bethesda.
Call +1-866-476-1348Our builder planned on damp-proofing only. We upgraded to a membrane and drainage board, and the basement has stayed dry since day one.
Jordan P., Bethesda
Water came in at three tie-rod holes every time it rained. The contractor injected each one from inside and the leaks stopped. Simple fix, fair price.
Mei L., Bethesda
Our old block foundation was always damp and chalky. They excavated one side, parged it, put on a membrane and new footing drain. Night and day difference.
Carl B., Bethesda
Fast scheduling and they texted photos of the membrane before backfilling. Very professional.
Ana V., Bethesda
Damp-proofing resists moisture vapor only. Waterproofing uses thicker, flexible membranes designed to stop liquid water under hydrostatic pressure.
Yes. The contractor excavates to the footing, cleans and repairs the wall, then applies a membrane, drainage board and footing drain before backfilling. It's more involved than interior work but stops water at the source.
Properly installed and protected membranes are built to last for many years. Ask the contractor for the manufacturer's rated lifespan and the written warranty terms.
Yes, because the expensive part, excavation, is already done. Retrofitting later costs far more.
Often. Interior injection is a common, effective fix. If many points leak, a broader solution may be more cost-effective.
It depends on your local building department and the scope. Excavation, drainage tie-ins and structural repairs are the most likely to need one, so ask the contractor who handles it.
We connect homeowners, builders and property owners throughout Bethesda with independent foundation waterproofing contractors who work locally. That covers new construction, additions and existing homes.
See the zip codes and nearby cities below, or call to confirm.
