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Best basement waterproofing pros near Sullivan, NH

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Top-Rated Basement waterproofing pros in Sullivan - Updated Nov 2026

Avatar for Northern Basement Systems
Northern Basement Systems
4.6(
21
)
Foundation, Basement or Crawlspace - Waterproofing / EncapsulationBasement Drainage Channels - InstallBasement Drainage Channels - Repair

Serving Sullivan, NH and surrounding areas

Approved

In business since 2010

Free estimates

Warranties offered

"Paul Swann evaluated our foundation problem and referred us to an engineer who provided a detailed repair plan. Unfortunately, the nature and scope of the proposed repair plan was outside the parameters of what Northern Basement System's themselves could provide. We appreciated their honesty and have been looking for a contractor to take on the project."
Additional Photos
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+25

Response time1 day
5 neighbors recently requested a quote
Recommended by88%of homeowners
Avatar for LeBlanc Basement Waterpoofing, LLC
LeBlanc Basement Waterpoofing, LLC
5.0(
3
)
Foundation, Basement or Crawlspace - Waterproofing / Encapsulation

Serving Sullivan, NH and surrounding areas

Approved

In business since 2007

Free estimates

Emergency services offered

"I was impressed with his knowledge and professionalism. He installed a French drain system with a vapor barrier on the walls. He prepped the area to protect our belongings, made sure everything was cleaned up after the end of each day, and provided exceptional service and quality. I would highly recommend him!"
Ion sump pump
Airtight solid sump cover
Ashburnham, MA.
Ashburnham, MA.
Ashburnham, MA.

+28

Response time1 day
8 neighbors recently requested a quote
Recommended by100%of homeowners
Avatar for Groundworks
Groundworks
4.6(
26
)
Foundation, Basement or Crawlspace - Waterproofing / EncapsulationBasement Drainage Channels - InstallBasement Drainage Channels - Repair

Serving Sullivan, NH and surrounding areas

Approved (Corporate)

In business since 1996

Free estimates

Warranties offered

"Joe,James and Bobby did an excellent job replacing the sump pump And drains. My husband and I were so impressed with their abilities and how hard working they were. I would highly recommend Ground works Manchester to anyone who needs the same work done. Thanks to all the gentlemen for their professionalism and work ethic"
Foundation
Foundation
Foundation
Basement
Basement

+16

Response time12 hrs
193 neighbors recently requested a quote
Recommended by56%of homeowners
Avatar for Freedom Framing and More, LLC
Freedom Framing and More, LLC
4.3(
14
)
Foundation, Basement or Crawlspace - Waterproofing / Encapsulation

Serving Sullivan, NH and surrounding areas

Approved

In business since 2014

Free estimates

Warranties offered

"I had a great experience with Freedom Framing! Matthew was very easy to work with and did a great job for a great price! Matthew is not only a great carpenter he is a very good project manager, ensuring the supporting contractors needed to complete the work arrived on time and performed top quality work. I would strongly recommend him for any construction work needed. I will be calling Matthew for the next project on my list! Excellent job Matthew! Thank you very much!"
Before
During
Wrapping up
Finished
Prep

+34

Response time2 days
Response rate95%
Recommended by84%of homeowners
Avatar for Basement Solutions LLC
Basement Solutions LLC
New to Angi
Foundation, Basement or Crawlspace - Waterproofing / EncapsulationBasement Drainage Channels - InstallBasement Drainage Channels - Repair

Serving Sullivan, NH and surrounding areas

Approved

In business since 2025

Free estimates

Warranties offered

We pride our company on reliability, integrity and quality work. We are experts in our trade. We look forward to earning your business! We specialize in concrete crack repair and injections, basement waterproofing, sump pump installations, basement and egress window installations, crawlspace repair, moisture control, foundation repair and so much more.\nCall us today for a free estimate.

Egress
Egress
Egress
Sump Pump
Perimeter System

+4

12 neighbors recently requested a quote
Showing 1-10 of 47
Basement Waterproofing FAQs, answered by experts

A crawl space is an area under the house that provides access to plumbing, electrical, heating ducts, and other HVAC units. Its purpose is to create a buffer between the ground and the living area, helping with ventilation, moisture control, and access for maintenance or repairs. Crawl spaces are most often seen in houses in North America which are built on concrete foundations versus other parts of the world where buildings are constructed differently.

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.

Water damage to concrete is often gradual and can take months, if not years, for a concrete structure to be fully destroyed. The process often starts with cracks on the surface, followed by sinking slabs and eventually crumbling cement. Therefore, it is important to repair minor damages early to prevent the situation from worsening.

While it’s possible to seal a foundation yourself, it’s not recommended, as it’s a tricky and labor-intensive job. Foundation sealing is best left to the pros to save yourself time, remove the risk of doing it wrong, and keeping yourself safe. Call a foundation repair professional near you to see what the job will cost.

The Sullivan, NH homeowners’ guide to basement waterproofing services

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