Top-rated basement waterproofing pros.

Get matched with top basement waterproofing pros in Cornish, NH

Enter your zip and get matched with up to 5 pros

Find Basement waterproofing pros in Cornish

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

Serving Cornish, NH and surrounding areas

Approved

In business since 2010

Free estimates

Warranties offered

"Northern basements was able to fit us in quickly, pulled our crooked cement wall back in-place and sealed the wall to prevent future leaks.  The work was timely, communication was friendly and detailed, and price was as to be expected for the large amount of work that needed to be done.  We are very pleased with the whole process as well as the results.
"
Additional Photos
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+25

Response time1 day
8 neighbors recently requested a quote
Recommended by88%of homeowners
Avatar for Groundworks
Groundworks
4.6(
26
)
Foundation, Basement or Crawlspace - Waterproofing / EncapsulationBasement Drainage Channels - RepairBasement Drainage Channels - Install

Serving Cornish, 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
234 neighbors recently requested a quote
Recommended by56%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 Cornish, 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

5 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 Cornish, 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
Avatar for Twin State Basement Services - Home  Facebook
Twin State Basement Services - Home Facebook
3.7(
7
)
Foundation, Basement or Crawlspace - Waterproofing / Encapsulation

Serving Cornish, NH and surrounding areas

In business since 2018

Free estimates

Credit card accepted

"I hired Twin State Basement Services to install perimeter drains in my basement after experiencing a water problem caused by hydraulic pressure under the floor. From the time I placed the phone call to the completion of the job it was clear to me that I was in excellent hands. I promptly received a call back within 24 hrs of it being placed. In all phases of the job from the size up and quote to the the completion of the job their work was beyond reproach. Refik and his crew were timely, efficient, courteous and professional. What impressed me the most was Refik's attention to detail and his personal commitment to "doing the job right". Nobody likes to have a water problem in their home but doing business with Twin State Basement Services made it much more palatable. This company was a great find for me. Highly recommend."
Response time3 days
Recommended by100%of homeowners
J & L Exteriors
4.9(
7
)
Basement Drainage Channels - InstallBasement Drainage Channels - RepairFoundation, Basement or Crawlspace - Waterproofing / Encapsulation

Serving Cornish, NH and surrounding areas

In business since 2009

Free estimates

"Overall it went pretty well.  They stared early and stayed late to make up time lost for rain.  They were very concientious about picking up every day.  John and his entire crew were very friendly and respectful. 

At first I wasn't very pleased with the number of visible seams in the flashing on the roof facing the driveway.  The roof is very "wavy" due to the settling of our ancient house and apparently the seams were unavoidable.  Everything has settled more and it is fine.  What is most important is that John talked to us about it and wanted to do anything he could to make sure we were happy with the job.

We would hire him again for work.  He seems to love what he does and he wants to make sure his customers are happy and it shows."
Recommended by100%of homeowners
Showing 1-10 of 33
Basement Waterproofing questions, answered by experts

The most flood-resistant materials you can count on in a flood scenario are concrete, closed-cell insulation, foam insulation (also known as expandable foam), pressure-treated wood, marine-grade plywood, and ceramic tile. When a material is flood-resistant, it can withstand direct contact with floodwater for at least 72 hours without being significantly damaged.

Mold and other fungi love moisture, so the best way to prevent mold growth after water damage is to remove as much moisture as possible. First, find the source of the water or moisture, such as a leak or clogged gutters, and correct the problem. Next, remove standing water, vacuum up puddles with a shop vacuum, and run blower fans and dehumidifiers for 24 to 72 hours. Once you've removed all traces of moisture, disinfect the area using either vinegar or bleach to kill any remaining mold spores.

A vapor barrier can last over 20 years, but they are vulnerable to pests, flooding, and other natural disasters. If your home weathers a storm or is treated for any pest infestation, make sure to have a drywall pro come check the integrity of your vapor barrier. It’s also important to have a pro install a vapor barrier since improper installation can lead to tears or leaks in the barrier that shorten its lifespan.

Yes, you can add a bathroom to an unfinished basement, but you’ll want to take proper precautions if doing so. As with any bathroom addition, you’ll need to make sure that it’s approved by local building authorities first. With unfinished basements, you especially need to keep an eye on proper ventilation practices.

Crawl space foundation problems can stem from a few different issues, but the most common are moisture and water problems and soil instability. Moisture and water issues are often a result of poor drainage, which can lead to water intrusion and soil expansion and contraction, leaving your foundation under added stress. A few things can cause soil instability, including poor drainage, karst landscapes and resulting sinkholes, and poorly compacted soil during construction.

The Cornish, NH homeowners’ guide to basement waterproofing services

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