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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
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Basement Waterproofing FAQs, answered by experts

A sump pump can remove excess moisture from under a house if standing water is present. Other ways to protect your crawl space from moisture include installing a vapor barrier, using a dehumidifier, installing insulation, and using a fan to dry the space. Finally, keeping your gutters clear of debris and positioning your downspouts away from the home’s foundation can prevent moisture from getting into the crawl space in the first place.

Crawl spaces are the more desirable option overall because they provide additional space for storage and utilities, but they are more expensive to install and maintain. Slab foundations are considered a better option in warmer climates where the depth of the frost line isn’t an issue because they’re more affordable, but crawl spaces are better in areas where the frost line is deep or where flooding can be an issue.

Home improvement grants are available for various groups, including individuals with very low-income housing, elderly people, older adults, and veterans. These grants can cover a range of needs, from accessibility modifications to addressing critical issues that may affect a resident's health or safety.

Yes, slab leaks are fairly common, especially in older homes and places that are prone to earthquakes which can move home foundations.

You don’t always need to install a dehumidifier in your encapsulated crawl space, but it might be a good idea in certain instances. If you notice obvious signs of condensation, mold, or musty smells permeating from your crawl space, a dehumidifier can help. It’s ideal for homes in humid areas.

In a worst case scenario, structural damage like rust on metal beams, rotting wood, and swelling on doors and windows can signal moisture problems that would benefit from a dehumidifier.

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.