Top-rated basement waterproofing pros.

Best basement waterproofing pros near Sullivan, NH

Enter your zip and get matched with up to 5 pros

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
6 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

Access to commercial-grade products and equipment, ensuring thorough coverage and long-lasting protection.

The most expensive foundation repair method is to install helical piers. Helical piers are a type of steel pier used to support sinking foundations in areas with poor soil conditions or deep bedrock. This foundation repair method can cost up to $3,000 per pier, including labor, because of its material and labor-intensive installation process. Total foundation repair costs can easily reach over $20,000 using this method.

The most cost-effective foundation repair is using masonry patches and sealants to seal foundation cracks and offer some support to prevent further damage. These methods are used to fix minor foundation cracks quickly. However, they’re not suitable as a long-term solution, and they only offer minimal stability. On average, masonry patches and sealants cost $500, but a sealant like an epoxy crack injection can total over $2,000. If you’re handy and only looking for a temporary solution until you contact a local foundation repair contractor for a more permanent one, you can save hundreds by DIYing this repair.

The best type of basement ventilation system depends on your budget, the moisture in your basement’s air, and the types of windows you have down there. You should consider all of these factors when choosing a ventilation system. However, the most effective method for basement ventilation is an energy recovery ventilator (ERV) or a whole-house ventilation system, which preheats or precools incoming air from the outside while also managing water vapor.

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.

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.