Top-rated basement waterproofing pros.

Best basement waterproofing pros near Grantham, NH

Enter your zip and get matched with up to 5 pros

Top-Rated Basement waterproofing pros in Grantham - 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 Grantham, 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
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 Grantham, 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
171 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 Grantham, 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

10 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 Grantham, 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 Grantham, 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 Grantham, 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 34
Basement Waterproofing FAQs, answered by experts

Proper basement ventilation is very effective at reducing humidity. Without enough ventilation, your basement is prone to mold and moisture damage. Your basement should have as much natural ventilation via windows and doors as possible, and if your budget allows, you should also consider installing an ERV system to keep basement humidity levels at bay.

In most cases, a crawl space will not dry out on its own unless the moisture comes from an uncommon flood and isn’t expected to be a recurring issue. For most homeowners, moisture problems in the crawl space will only continue to get worse over time, so addressing the underlying problem with gutter systems or a foundation drainage system and setting up a preventative solution like a dehumidifier is necessary.

Unfortunately, mold can grow pretty much anywhere, on any kind of surface. However, you’re most likely to see it in damp areas like basements or bathrooms, as well as anywhere there has been a water leak. Consult a local mold specialist to determine if certain areas of your home are prone to mold based on climate and other factors.

Flooded basement cleanup can take anywhere from a few days to several weeks, depending on the extent of water damage, the type of water involved, and the need for repairs or mold remediation. Severe cases with structural damage or extensive mold may require longer timelines. Quick action and professional help can speed up the process and reduce overall damage.

Yes, crawl spaces can attract bugs, especially since moisture tends to build up in the space, and moisture attracts pests. A good way to prevent pest infestation in your crawl space is to install a vapor barrier—called crawl space encapsulation—on the interior to seal the space, along with a French drain or some other kind of foundation drainage system outside to keep runoff out of your crawl space. You can also seal foundation cracks and repair damages to cut off access to pests.

The Grantham, NH homeowners’ guide to basement waterproofing services

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