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Best basement waterproofing pros near Union Gap, WA

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Top-Rated Basement waterproofing pros in Union Gap - Updated Nov 2026

Avatar for TerraFirma
TerraFirma
4.1(
100
)
Foundation, Basement or Crawlspace - Waterproofing / EncapsulationBasement Drainage Channels - InstallBasement Drainage Channels - Repair

Serving Union Gap, WA and surrounding areas

Approved

In business since 2005

Free estimates

Warranties offered

"I was please with the estimator, Boston's knowledge and willingness to walk me through the process and unfamiliar territory of basement waterproofing. He was very knowledgeable and answers so many questions, at the time of the walk through as well as in the days after when I had questions after receiving other bids and trying to compare them. In the end, it was just my low budget that kept me from going with Terra Firma. I thought their system was excellent, and would have worked well with my basement, but I had to opt for a less expensive design."
A System Design Specialist helping a homeowner
Encapsulating a crawl space
Fleet of vehicles in our Portland, Oregon locatio
Loading up our truck for a piering job
Loading up a truck for a waterproofing job

+33

Response time10 mins
Response rate100%
115 neighbors recently requested a quote
Avatar for MTU Services LLC
MTU Services LLC
5.0(
5
)
Foundation, Basement or Crawlspace - Waterproofing / EncapsulationBasement Drainage Channels - InstallBasement Drainage Channels - Repair

Serving Union Gap, WA and surrounding areas

Approved

In business since 2021

Free estimates

Emergency services offered

"We’ve had a lot of crews in our home for various projects over the years, and I have to say this was one of the most courteous. They worked hard, navigating through our kitchen to access the basement and I really appreciated their efforts. Thank you MTU, we now have safe walls in our cellar and fresh beams to keep the house standing ;)"
Elevator pit waterproofing and sealing
Piers under an existing home
Piers under an existing homes middle wall
Solutions/Answers
Response time1 day
Response rate100%
4 neighbors recently requested a quote
Avatar for Campbell & Company
Campbell & Company
4.6(
166
)
Basement Drainage Channels - InstallBasement Drainage Channels - Repair

Serving Union Gap, WA and surrounding areas

Approved (Corporate)

In business since 1983

Free estimates

Credit card accepted

HEATING, COOLING, ELECTRICAL, SOLAR, PLUMBING, AND\nDRAIN SERVICES IN THE TRI-CITIES & YAKIMA, WA\nSpeedy Response - Expertise and Experience - Efficient Troubleshooting - Quality Workmanship - Transparent Pricing - Excellent Customer Service\n\nAre you facing an HVAC breakdown, a plumbing emergency, electrical issues, or considering a solar energy upgrade? Look no further! We are your trusted experts in HVAC, plumbing, electrical repairs, generator needs and solar energy solutions, and we're here to solve your problems swiftly and efficiently.

31 neighbors recently requested a quote
Recommended by87%of homeowners
Avatar for Mr. Rooter Plumbing
Mr. Rooter Plumbing
4.6(
5
)
Basement Drainage Channels - InstallBasement Drainage Channels - Repair

Serving Union Gap, WA and surrounding areas

Approved

In business since 1997

Free estimates

Emergency services offered

Thank you for considering hiring us for your project! At Mr. Rooter Plumbing we pride ourselves on quality work, integrity and competitive pricing. We believe in giving our absolute best, no matter how big or small your project. \nWe are experts in our trade, and we will keep you educated and informed throughout the completion of your project. We treat your property like it's our own, with the utmost respect, just like we would our own family! \nAs the owner, my aim is to earn a 5-star review on the completion of your project. So, please let me know if at any time we are not living up to earning your perfect 5-star review. \nWe look forward to earning your business, so please ask us for references!

Plumbing
Response time8 hrs
Response rate100%
8 neighbors recently requested a quote
Avatar for TerraFirma Foundation Systems
TerraFirma Foundation Systems
4.4(
238
)
Basement Drainage Channels - InstallBasement Drainage Channels - RepairFoundation, Basement or Crawlspace - Waterproofing / Encapsulation

Serving Union Gap, WA and surrounding areas

In business since 2005

Free estimates

Emergency services offered

"I used TerraFirma to install a sump pump in my leaking basement. The team that worked on installation were great to work with. I was very pleased with the quality of work, the communication throughout the process, and their respect for my home."
Additional Photos
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+11

Response time7 hrs
Response rate100%
Recommended by89%of homeowners
Avatar for Stenersen Excavating, Inc.
Stenersen Excavating, Inc.
5.0(
2
)
Basement Drainage Channels - Install

Serving Union Gap, WA and surrounding areas

In business since 2023

Free estimates

Credit card accepted

Stenersen Excavating, Inc. is owned by Kenneth Stenersen. At Stenersen Excavating, we proudly continue the legacy of Kenneth’s father who spent over 40 years in the excavating business. Growing up surrounded by machines from a young age, we have developed a profound understanding of the industry. Our expertise and experience allow us to provide exceptional excavating services tailored to your needs. Integrity is our top priority, and we adhere to strict guidelines to protect our team and clients. At Stenersen Excavating, we value open communication and transparency, building lasting relationships with our clients. Trust us to deliver outstanding results, backed by a lifetime of experience and a passion of the excavating business.

Drainfield
Drainlines
Drainline
Backfill
Tank Replacement

+4

Response time5 hrs
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Basement Waterproofing FAQs, answered by experts

If you notice standing water under the deck after rainstorms, you may need a drainage system to efficiently move this water. You do not want standing water to rest against your foundation or against support posts for the deck, as this could cause significant structural problems over time. Make sure the area has proper grading, too.

You should always hire a structural engineer or a professional and licensed foundation repair company for crawl space repair. These professionals will often be able to treat the symptoms of the issue as well as the underlying problem so that you don’t have ongoing damage. They’ll also often take preventative measures to stop the issue from recurring in the future.

Ideal humidity conditions generally range from 30% to 50%, with 45% considered optimal humidity for most homes. If your humidity levels drop below that range, you can turn your dehumidifier off. Additionally, suppose the temperature where the dehumidifier is installed falls below 60 degrees Fahrenheit. In that case, it's best to turn it off and unplug it since cooler temperatures can cause the unit's coils to freeze.

The best basement waterproofing method depends on the specific issue causing the water intrusion. For minor problems, simple solutions like installing a properly functioning gutter system to direct runoff away and grading the soil to slope away from your foundation can be effective.

If you have more significant water problems, the solution will need to be more robust:

  • For standing water on the basement floor, a floor drain or a sump pump system may be the best solution.

  • For water pooling around the foundation, installing an exterior French drain can intercept water before it reaches the basement walls.

Other effective waterproofing methods, which can be used depending on your home's specific needs, climate, and soil type, include sealing the interior walls, landscape alteration, installing interior drainage systems, and using a dehumidification system to control moisture levels.

The primary reason homes have crawl spaces is so the foundation can reach down below the frost line to avoid dangerous soil movement and structural damage when the ground freezes. They’re more popular in colder climates where the ground freezes down to a few feet, and slabs are most popular in warmer areas where there is no frost line. Crawl spaces also provide a space for utility lines to run where they’re at less of a risk of freezing.

The Union Gap, WA homeowners’ guide to basement waterproofing services

From average costs to expert advice, get all the answers you need to get your job done.