Foundation Waterproofing & Drainage Services Across the Seattle Area

The Right Basement Waterproofing. The Bright Result.
trust point of basement expert. 5 star reviews and NDS-Certified basement waterproofing specialists

Based in Lynnwood · 7+ Years Protecting Basements & Foundations Across the Seattle Area

+1 (206) 388-7867

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No Fluff. No Passive Barriers. Just Drainage Built to Last.

Top-Rated on Google – See Why Customers Love Us:

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Tanya Eng-Aquino profile picture
Tanya Eng-Aquino
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We had a really great experience with Basement Expert and couldn't be happier with the work they did! Vlad initially came out to seal a crack in our foundation wall and assess what else needed to be done to address the water intrusion. The following week, a crew came back to install an interior French drain system. From the beginning, everyone was professional, friendly, and easy to work with. They took the time to explain the process, show us what they were doing at each stage, and walk us through how everything would work. I was amazed at how precisely they cut the concrete floor and how neatly they installed the entire system. You could tell they really take pride in their work. When the job was finished, the work area was all cleaned up. They removed all the debris and cleaned everything up that you'd hardly know they had been there! What really sets this company apart, though, is that their service didn't end when the job was done. Several weeks later, they followed up to check on how the system was functioning and make sure everything was working as expected. That extra step really meant a lot and showed us that they genuinely care about their customers, not just completing the job. It's not always easy to find contractors who deliver on their promises, do quality work, and genuinely care about the customer experience, but Basement Expert did all three. They exceeded our expectations, and we wouldn't hesitate to recommend them to anyone requiring similar services.
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Mark profile picture
Mark
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They do a free inspection which is super nice as a single unit condo owner. The input I received was extremely helpful - I learned several things about my home I was totally unaware of. They are transparent, honest, and highly knowledgeable. I will definitely use their services in the future if I have the chance to use them over other similar businesses.
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Ed Matt profile picture
Ed Matt
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The Basement Expert crew came out to replace a broken T fitting on my out door underground drainage system for my house. The T fitting was in a deep ditch and the job took twice as long as was anticipated because it was a difficult location and they even kept the original estimate which was very reasonable to begin with. They got the job done and everything turn out great. I highly recommended them.
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Long Tran
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Very knowledgeable and provides a lot of good options. Definitely worth a call.
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Anne Erickson profile picture
Anne Erickson
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We used them to help with a rock well for our sump pump and they were quick, affordable, very communicative, and professional! I would use them again in the future if I needed them!
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Carr Onstott
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Just had a set of french drains and new downspout drains installed and we couldn't be happier with the work. The owner was very responsive and helpful. We called on a Thursday afternoon after seeing some water in our basement and he came right out that evening and got started the very next morning. They did an excellent job cleaning up after themselves every day and even helped me out with a few minor touch ups. Would absolutely recommend them to anyone else needing some work done.
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Tanya Nadkarni profile picture
Tanya Nadkarni
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They were very responsive and came by and provided a reasonable estimate quickly. They waterproofed my basement (had a mold issue which prompted me to reach out to them) and I haven’t had any issues so far. Worked fast and explained clearly what needed to be done.
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Kyle Karpack profile picture
Kyle Karpack
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Vlad and the Basement Expert team did a fantastic job installing a complete perimeter drain and waterproofing system in our unfinished basement. We appreciated that they were timely, clean, clear communicators, and most of all, that they did excellent work. Our project was challenging, but they were ready to tackle everything that came up including plumbing changes and having to trench around a large boulder, without any unexpected costs on our side. From the start, Vlad’s evaluation of our project was honest and thorough, and they were transparent with pricing and the scope of work. The pricing was competitive and we felt that their team went above and beyond with their excellent workmanship and attention to detail. Throughout the project, they explained what they were doing and consistently made great decisions. For anyone needing a sump pump, french drain, or other basement waterproofing services, I’d recommend Basement Expert without any hesitation!
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Eva Papp profile picture
Eva Papp
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Vlad of Basement Expert Waterproofing recently diagnosed my basement leak issue. He came with scopes and moisture readers, and was able to not only verify the condition of work I had done previously with another company, but suggest what a reasonable fix would be. He came out the day after I called, and while we had planned to do the job the following week, he was able to complete the job the same day when space opened up in his schedule. I can’t believe it. In the midst of rainy season I got a same day fix with a new rock well and diversion system. These guys are honest, professional, timely, and cost effective. Total pleasure working with them, and they will for sure be the first ones I call if ever I need this type of service again. Thanks Vlad and crew.
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Daniel Gus Schreiner profile picture
Daniel Gus Schreiner
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We highly recommend Basement Expert. Being new to the area we talked with a lot of companies about waterproofing and other house projects and we were initially impressed with Basement expert's clear communication and they didn't seem like they were trying to sell us something we didn't need. After hiring them, the clear communication continued and we found them to have integrity and take pride in their work. They were also very clear and fair about pricing and definitely earned our trust. We can now rest easy when there is heavy rain knowing that their work is protecting our home and the money we have put into our other improvements!
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Licensed, Insured, and NDS-Certified

Basement Expert, a division of Artbrick LLC (WA Reg: ARTBRL*812B8 — verify on L&I)

Illustrative infographic banner comparing a dry, protected Seattle basement cross-section with a robust interior drainage system and sump pump against an exterior foundation experiencing heavy rain, hydrostatic pressure, and clay soil seepage. Includes text reading: "PROTECT YOUR SEATTLE BASEMENT FROM DAMPNESS & FLOODING.

Basement Expert is an NDS-certified contractor for below-grade water control, foundation drainage, and structural moisture problems across the Greater Seattle area, including Seattle, Bellevue, Everett, and Marysville. As an NDS-Certified Drainage Contractor and Public Works Trained specialist, we go beyond surface fixes to solve the root causes of hydrostatic pressure and soil instability.

Our Specialized Service Suite:

  • Basement & Garage Waterproofing: Comprehensive interior and exterior systems for wet basement repair and solutions, including polymer-based sealants and dimple board membranes specifically for below-grade garages and basements.

  • Structural Reinforcement: High-load stabilization for foundation footings, foundation belts, and failing retaining walls.

  • Advanced Drainage Systems: Custom-engineered French drains, yard drainage, and high-capacity discharge pump replacements.

  • Crawlspace Water Management: We specialize in active drainage solutions (French drains and dimple board systems) to remove standing water. Please note: We do not offer crawl-space plastic encapsulating systems; we focus on active water diversion and structural health.

  • Restoration & Remediation: Professional mold remediation and commercial water damage restoration.

  • Basement Flood Restoration and waterproofing.

Basement Waterproofing & Foundation Drainage Systems We Specialize In

Our systems don’t just block water; they relieve the hydrostatic pressure and lateral loads that cause foundation walls to bow and footings to settle.

Some jobs need a different kind of fix. When walls or footings are moving, that is structural foundation work. When water has to be carried away from the footing, that is a drain line. When the basin has to lift water out, that is a pump. Each of those has its own page in the service cards below.

Waterproofing & Foundation Repair Costs: Transparent Investment Benchmarks

Understanding what below-grade water-control work costs in the Seattle area can help you make smarter decisions before you invest. From discharge pump systems and interior perimeter drainage to foundation crack repair and exterior solutions, our detailed cost guide breaks down price ranges, what affects pricing, and what you can expect for your home. Learn more about local below-grade water-control costs and plan your project with confidence:
👉 Seattle Below-Grade Water-Control Costs & Pricing

Services Quick Overview

Service Description CTA
Interior Waterproofing Collect and redirect water before it reaches your basement floor. Learn More
Exterior Waterproofing Stop water before it hits your foundation with engineered solutions. Learn More
Discharge Pump Installation High-performance pumps with battery backup to handle Seattle’s high water tables. Learn More
Crack & Wall Repair Structural and non-structural foundation crack repair using carbon fiber and epoxy systems. Learn More

Our Crawlspace Waterproofing Services

The Basement Expert Standard: Why We Don’t “Encapsulate”

While many companies offer crawl-space plastic encapsulating systems (trapping moisture behind plastic), we believe in Active Water Removal.

  • Our Method: We install high-capacity French drains and dimple board systems to catch and divert water before it enters your crawlspace or garage.

  • The Result: A dry, structurally sound foundation that breathes, preventing the rot and “stagnant water” issues common with traditional encapsulation.

Structural Foundation Repair: Carbon Fiber Reinforcement & Crack Stabilization

Diagram for structural reinforcement by Basement Expert

Some water issues in the Puget Sound come with structural stress. When walls or footings need reinforcement, we stabilize the load paths — the “bones” of your home:

  • Foundation Footing Repair: Stabilizing sinking or shifting footings in unstable PNW soils.

  • Foundation Belt Systems: Reinforced bracing to prevent lateral wall failure.

  • Retaining Wall Restoration: Relieving hydrostatic pressure and reinforcing failing site walls.

Understanding Hydrostatic Pressure in Your Basement

Reviews

We needed a real plan for a wet basement – Basement Expert gave us a very competitive and prompt quote. Serhii and Nazar were very responsive and professional. They and their crew were polite, efficient, and thorough. They went above and beyond, even doing a few minor improvements above and beyond the original project scope. I would highly recommend them.

Akshay

Nazar and Sergii from Basement Expert, along with their technicians did an excellent job installing a new interior perimeter drain system in 2/3 of our basement. Pricing was fair, communication was very good, the work went smoothly and quickly and the real test will be next winter . . but I have every reason to believe that we will dry and happy going forward. Recommended to anyone with damp basement worries.

Steve

I highly recommend Basement Expert. They definitely adopt a proactive approach to waterproofing vs a reactive one. Case in point: we had drainage issues in our crawl space which resulted in a lot of standing water. My initial reaction was to get someone to clear the drain and install a discharge pump in the crawlspace, but Basement Expert suggested to be proactive and catch the water from entering our house in the first place. They hand-dug trenches around the exterior and waterproofed the outside of our house, installed sturdy french drains, exterior sump, disposal drain, and even replaced some very old and damaged downspouts they found on our property. They are very mindful of gradients and slopes to encourage water drainage and despite all the digging that was needed, our grounds is in better condition now than it was before! Lots of work and they were done within a week. All for a very fair and comparable price. They were very professional, always showed up in uniform, and consistently quick to respond. We whole heartedly recommend them to our neighbors and friends, and would hire them again without hesitation! Very impressed!

Connie

Thank specialists from Basement Expert so much, they did an incredible job on our crawlspace waterproofing. They were extremely professional and efficient while they worked. I would highly recommend Basement Expert if you need any crawl space work done and specifically these three men to do the job!

Tommy

I appreciated the great customer service that I received from the company. I am really impressed by the level of professionalism that I experienced from the basement-expert. The work was done efficiently, neatly and in a timely manner. I recommend this company!

Jane
We turned to Basement Expert for help. We have had problems with dampness for many months. Company employees came and did everything for us, thank you very much.
Pati

Faced with dampness in the basement, on the recommendation they called professionals from Basement Expert, made good waterproofing, air vents, now we don’t know grief — everything is dry.

Taras

There was always a problem with humidity in the basement. Basement Expert suggested the best solution and did everything professionally.

Aleksandr

In my garage in the basement, moisture and condensation constantly accumulated on the ceiling. Even the foundation began to crumble. An unpleasant sight. A friend advised me to contact the firm Basement Expert. I didn’t expect that my problem would be solved in a week. I am satisfied with the price and quality of the work done.

John
Schedule Your Free Foundation Inspection

Our Proven Process for Dry Below-Grade Space — Step by Step

1. INSPECTION

2. ESTIMATE

3. SCHEDULE WORKFLOW

4. COMPLETE SERVICE

5. HAPPY CLIENTS

The “Basement Expert” Technical Resource Library

Engineered Solutions for Seattle’s Unique Foundation Challenges

At Basement Expert, we believe an informed homeowner is a protected homeowner. We don’t just provide “fixes”—we provide NDS-certified drainage work and active water management. Explore our technical archives for deep dives into the science of foundation health.

Field notes and structural guides

Want more detail on hydrostatic loads, glacial till, and below-grade assemblies? The library keeps the long-form notes.

Engineered Infrastructure & Residential Protection

Resource Category Technical Focus & Engineering Specs
Commercial Restoration High-capacity water extraction, Elevator Pit Waterproofing, and large-scale apartment building logistics.
Discharge Pump Engineering High-capacity pumping, Total Dynamic Head calculations, and battery-backup options when the site needs them.
Foundation & Structural Health PNW Soil Science (Glacial Till), Carbon Fiber wall reinforcement, and structural crack analysis.
Basement Flood Restoration The science of LGR Structural Drying, microbial control, and Category 3 flood mitigation.
Waterproofing & Drainage Active hydrostatic pressure relief vs. passive sealants. Engineered French Drains and exterior excavation.
Local Compliance & Logistics Unit-Based Pricing, Seattle/Bellevue permit requirements, and our professional crew protocols.
Industry Comparisons The reality of “Lifetime Warranties” and the technical case against crawl-space plastic encapsulating systems.

Why Technical Transparency Matters

“Most contractors offer a ‘patch-and-paint’ warranty. We focus on how your home interacts with soil and water. From understanding Seattle’s Soil Science to mastering Total Dynamic Head in pumping, our library is built to show you exactly how we protect your greatest investment.”

Keeping Basements & Foundations Dry Across the Seattle Area

Is your basement prone to leaks and water damage? Protect your property investment with drainage and waterproofing systems built for Puget Sound homes. We use the latest technology and techniques to keep your basement dry and prevent costly repairs. Our team of experts will assess your needs and provide a tailored solution that meets your goals. Schedule your free foundation inspection and we will walk the water path with you.

Interior Basement Waterproofing: Sub-Slab Drainage & Hydrostatic Relief

If you think that you need assistance with waterproofing basement from the inside, the best thing you can do is call the team of specialists that will come to your house and inspect it. Our employees will arrive as soon as possible and will see what the problem is.

While every home is unique, controlling water at the foundation in the Seattle area is a strategic investment in structural preservation. On average, high-performance interior drainage systems carry a project cost of approximately $140 to $180 per linear foot. For most residential properties in the Puget Sound region, this translates to a total project investment ranging from $5,000 to $13,500, depending on the basement perimeter and the specific hydrostatic pressure challenges of your site.

Exterior Foundation Waterproofing: Full Excavation, Membranes & Footing Drains

Waterproofing basement from the outside is another kind of services we are eager to suggest to you if you need it. Again, first of all, we will have to arrive at the place of your residence to find out the cause of the wet in the basement. If we see that it lies outside, we will offer some of the solutions to you. Pay attention to the fact that such work will cost more as long as we might involve some heavy tools and machinery.

Commercial Waterproofing & Water Damage Restoration

A leaky basement can be a nightmare for commercial property owners in the Puget Sound region. As a trusted commercial below-grade water-control contractor, we provide tailored solutions to protect your property investment. From waterproofing membranes to drainage systems, we offer a range of services to keep your basement dry and damage-free.

It doesn’t really matter whether you want to repair a new construction or you want to ask us to deal with older buildings in the region. We will be eager to suggest our qualitative help in both cases.

It is really important to take proper care of the basement in case we speak about the commercial buildings in this area. If you do not notice the problem on time, you may risk your sales and accordingly, your income from this.

That is why consider this: if you see that the issue with your commercial basement is minor, do not postpone its “treatment”. It will help you to:

  • Avoid more serious consequences;
  • Reduce the costs of the repairs;
  • Continue dealing with your business effectively.

And, the professional work in your area won’t take too much time too.

Residential Foundation Protection: Protecting the Future of Your Home

As all of us know, the home is a place we should take care of. And, the basement is not an exception here. So, in case you see that there is water or mold in the basement, it’s time to ask for the advanced help that will help you to get rid of all this and save your house in the best condition possible.

We are a reliable below-grade contractor serving the Puget Sound that knows how to eliminate your problem no matter how great it is. Why bother thinking about the stuff like “Can I waterproof my basement on my own?” when you can stick to our local assistance. We are always nearby to offer our services.

Our specialists will inspect your home to see what the issue is linked to. After this, you will receive an estimate to figure the approximate price out. We will be glad to help!

FAQ

Usually yes — when the system matches how water actually enters. A dry, usable basement is far easier to store belongings in or finish later.
Absolutely. You can order such services if you need them and we will be pleased to promote the best assistance possible. We’ll explain scope and cost before work starts.
We naturally can. First of all, we will inspect your basement and home to make sure what exactly we will have to do. If you are going to need exterior waterproofing, we will be eager to help with this.

Cost depends on perimeter, access, and soil/water conditions. Our interior water-control systems typically fall between $5,000 and $13,500 for most residential basements — we’ll confirm after inspection.

While it’s possible to attempt this yourself, trusting experienced professionals is the smarter choice. A professional below-grade water-control plan aims for durable, long-lasting results — addressing basement leaks at the source and reducing moisture intrusion, foundation seepage, and water damage.