Top-rated basement waterproofing pros.

Best basement waterproofing pros near Sunapee, NH

Enter your zip and get matched with up to 5 pros

Top-Rated Basement waterproofing pros in Sunapee - 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 Sunapee, 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
3 neighbors recently requested a quote
Recommended by88%of homeowners
Avatar for Groundworks
Groundworks
4.6(
26
)
Foundation, Basement or Crawlspace - Waterproofing / EncapsulationBasement Drainage Channels - InstallBasement Drainage Channels - Repair

Serving Sunapee, 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
173 neighbors recently requested a quote
Recommended by56%of homeowners
Avatar for Quantum Contracting, LLC
Quantum Contracting, LLC
4.3(
38
)
Basement Drainage Channels - Install

Serving Sunapee, NH and surrounding areas

Approved

In business since 2015

Free estimates

Credit card accepted

"Quantum Contracting is great! Tyler and Austin are very professional and hard workers. Very efficient and my porch looks fantastic. I would hire them again in a flash and they are very honest and fair and really know what they are doing."
Small Garden
Complete Landscape Renovation
Grade Work
Brick Pathway
Small Retaining Wall

+23

Response time2 days
Response rate89%
11 neighbors recently requested a quote
Avatar for Freedom Framing and More, LLC
Freedom Framing and More, LLC
4.3(
14
)
Foundation, Basement or Crawlspace - Waterproofing / Encapsulation

Serving Sunapee, 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 Sunapee, 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

11 neighbors recently requested a quote
Avatar for Green Mountain Basement Solutions LLC
Green Mountain Basement Solutions LLC
4.0(
30
)
Basement Drainage Channels - InstallBasement Drainage Channels - RepairFoundation, Basement or Crawlspace - Waterproofing / Encapsulation

Serving Sunapee, NH and surrounding areas

In business since 2007

Free estimates

Emergency services offered

"The work itself, the actual basement waterproofing appears to be working but our flood season hasn't come yet so, I'm reserving judgement. But, the way the work was done was a problem and the initial way that they got with the problem wasn't satisfactory. Eventually, months after work I did get some resolution but is wasn't a smooth transaction. We moved some of the finished portions of the basement to do their work and the way that that was handled was very sloppy and rushed, and very expensive to repair. And then, when the initial point of having somebody come and look at all my questions, it was not the owner, it was his foreman and it was not dealt within a professional manner. After 2 contacts, tried to explain what the problems were and has offered that they have an annual service to make sure that everything is working and there's a fee for that, though he offered 2 years of that with no cost, so that was a nice gesture. He tried to make up for the problems but like I said, there were problems."
Recommended by75%of homeowners
Showing 1-10 of 42
Basement Waterproofing FAQs, answered by experts

A crawl space encapsulation isn’t always necessary, but it’s a wise choice, especially if you live in an area that sees a lot of precipitation. Sealing a crawl space not only reduces damage caused by moisture, mold, and pests, but it also increases your home’s value. It can also save you money by reducing energy bills and avoiding costly repairs for structural or foundation damage.

Whether to waterproof your basement from the interior or exterior depends on several factors, including your budget.

Exterior waterproofing is generally considered the superior method because it stops water at the source, preventing it from seeping into and damaging your basement walls. This approach offers the most protection, making it ideal if you use your basement for storage.

By contrast, interior waterproofing is often less expensive and requires less labor because the area is more accessible.

For maximum protection against water leakage and moisture, applying waterproofing measures to both the inside and outside is the best solution. However, if you must choose only one, stopping water from the outside is the most effective approach to preserve your foundation and prevent damage.

Physically, the most challenging part of finishing a basement is installing egress windows or doors when the space is below ground level. Mentally, the hardest part may be envisioning the project and planning around load-bearing and mechanical obstacles.

Regular inspections, proper drainage management, and ensuring soil stability help prevent future settlement issues.

The process might take a few days to a week, depending on the method chosen, area size, and weather conditions. Some solutions, like simple interior sealants, may require less time.

The Sunapee, NH homeowners’ guide to basement waterproofing services

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