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Find Basement remodelers in Portsmouth

Avatar for NH Projects LLC
NH Projects LLC
5.0(
19
)

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2021

Free estimates

Customers say: Quick response

"Lenny and Nick are great to work with! We are finishing our basement and they just completed the bathroom to start and it came out fantastic! They have excellent contacts to help with the plumbing and electricity and made the whole process easy for us. We can't wait to keep working with them and completing our basement."
Our Work
Our Work
Our Work
Our Work
Our Work

+8

Response time5 hrs
2 neighbors recently requested a quote
Recommended by84%of homeowners
Avatar for The Hurlburt Group, LLC
The Hurlburt Group, LLC
4.7(
29
)

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2007

Free estimates

Small jobs welcome

"Basement Finish Project: Dave Hurlburt and his team were amazing. They were quick but thorough and provided great customer service. Dave was flexible and wanted to provide the best service possible. Not to mention they provided a very fair price for the project. I would recommend this crew for any project."
basement subfloor
garage door
new beam header
garage door
closet

+77

Response time3 days
Response rate88%
9 neighbors recently requested a quote
Avatar for MMP Construction Inc
MMP Construction Inc
4.7(
191
)

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2004

Free estimates

Emergency services offered

"We had a very small roof area need to be repaired. I sent request to multiple company to give a service quote. Few of them sent me replies and stated that they are too busy to come. Matt of MMP Consturction's contacted me promptly, scheduled an on-site visit and gave us a quote right away. The work was then scheduled and finished quickly. Matt did great job on reaching out, effective communication, and always arriving on-time. He also gave an evaluation on our roof condition. Also, Eric and Don did excellent job on finishing the project. They are all very polite, knowledgeable, and showed their professionalism. We would like to express our sincere appreciation to Matt and his crew. We are very grateful for having them arriving on-time before the winter storm to prevent potential damage of the house. From their react, we see a warm heart. No job is big or small, all jobs are equally important. Understanding the difficulties of others, for the people, been appreciated by the people. Thank you again for your high quality service. We definitively recommend MMP Construction Inc. to anyone for any related home project."
Additional Photos
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+154

1 neighbors recently requested a quote
Recommended by89%of homeowners
Avatar for IDEAL SOLUTIONS LLC
IDEAL SOLUTIONS LLC
4.8(
12
)

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2020

Free estimates

Credit card accepted

" I had an excellent experience with Ideal Solutions on my basement remodel. From start to finish, the team was professional, communicative, and detail-oriented. The quality of the work exceeded my expectations, and the finished basement turned out even better than I imagined. Everything was completed on time, and they made the entire process smooth and stress-free. I would absolutely recommend Ideal Solutions to anyone looking for basement remodeling or home improvement work."
2 neighbors recently requested a quote
Recommended by66%of homeowners
Avatar for DCL Construction
DCL Construction
5.0(
9
)

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2000

Free estimates

Emergency services offered

"We have been wanting to finish our basement for a very long time now but the prices we were given were too high! A friend of ours referred DCL to us and we thought we would give them a shot. The price was right so we started shortly after. They took care of all the paperwork and permits needed! Bob was there for the whole process discussing with us every step of the remodel! Very knowledgable and very well trained team! Our basement looks incredible and we enjoy spending time there! I would recommend DCL to anyone!!"
Completed jobs or on goin
Basement remodel
Basement remodel bathroom added
Basement remodel and bath room added
Basement remodel

+24

Response time6 hrs
7 neighbors recently requested a quote
Recommended by66%of homeowners
Hamill Home Improvements
4.8(
25
)

Serving Portsmouth, NH and surrounding areas

Approved

In business since 1987

Free estimates

Small jobs welcome

"Jim was a consummate professional from start to finish. He gave a very detailed quote, patiently answered all our questions, and started the project weeks before we ever thought we'd get a contractor to start. The work was fantastic. Our basement came out beautiful and Jim was a pleasure to work with. He did everything exactly as designed, communicated progress, and was very responsive if we needed anything. He was also very knowledgeable about the various options for finishes, flooring options, etc, and even had some contacts with local businesses that gave us good prices for some of the materials. I highly recommend Hamil Improvement for any remodeling project. Would definitely work with them again!"
Kitchen Remodel
Master Bedrood
New windows and door
Kitchen Remodel
Master bedroom

+133

Response time1 day
Recommended by88%of homeowners
Avatar for Boyd Building
Boyd Building
5.0(
17
)

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2001

Free estimates

Emergency services offered

"Boyd Building had done some work for us in the past so when we needed a major deck and porch rebuild and finish, we knew Shawn would be the only one to call. Shawn always goes above and beyond in planning and executing our projects. He once told me that he puts the same amount of quality and care into the work he does on a customer's home as he would on his own home and I truly believe him. His work is detailed and meticulous. The job he did remodeling our outside space is top quality. There is not one thing we had to question. We love everything! Beyond that he is reliable, honest, trustworthy, hardworking and a really nice guy. We can't possibly recommend Boyd Building any higher! 5 stars don't seem like enough! "
Stone veneer
Stone veneer
Stone veneer
Stone veneer
Stone veneer

+80

Response time2 hrs
4 neighbors recently requested a quote
Recommended by70%of homeowners
Avatar for Horsman Builders
Horsman Builders
5.0(
19
)

Serving Portsmouth, NH and surrounding areas

Approved

In business since 1986

Free estimates

Emergency services offered

"I would not hesitate for a second hiring Horsman Builders for any of my house projects or remodel, in fact that is what I will do from now on. I was nervous starting a project having to handle things on my own but Tim made me comfortable with a detailed estimate, answered all my questions, kept me informed about the work, the site was always clean and the result is awesome, my neighbor was commenting on how great it is just checking it out from a window. Fair price, excellent quality and great customer service. A+"
General Remodeling Project
General Remodeling Project
Additional Photos
Additional Photos
Additional Photos

+4

Response time6 hrs
2 neighbors recently requested a quote
Recommended by100%of homeowners
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FAQs for basement remodeling projects in Portsmouth, NH

Finishing a basement turns unused square footage into livable space and returns up to 70% of what you spend when you sell your home. Beyond that resale boost, you gain a playroom, home office, or guest suite you can start enjoying right away. That mix of daily comfort and solid return on investment (ROI) makes basement finishing one of the smartest upgrades you can tackle.

In some parts of the country—especially lots on swamps, high water tables, or other wetlands—local codes prohibit basements. Saturated soil puts constant pressure on foundation walls and lets water seep in faster than any sump pump can handle. 

If your property sits on waterlogged ground, building on a slab or crawl space is often safer, more affordable, and code-compliant.

Most basements wrap up in four to eight weeks. Framing takes three to five days, with electrical and plumbing rough-ins following over the next week. Add five days for drywall, two to three for flooring, and another week for paint, trim, and punch-list items. 

Delays can happen if materials run late or your contractor’s calendar is packed, so build in a little cushion when you plan.

Whether a finished basement counts toward your home’s official square footage depends on local rules. Many areas only include below-grade space if it has code-approved egress, fully finished walls, ceilings, and floors, plus consistent heating. 

Check with your local assessor or building department before you start; meeting those standards can affect taxes, appraisals, and resale value.

Building codes require a checklist: dedicated heat and electrical service, a code-approved stairway, and at least one egress window or exterior door. Walls, ceilings, and floors must be fully finished and meet insulation, ventilation, and fire-separation standards. If you add a bedroom, you’ll also need a closet, proper clearances, and safe exits. If you change the layout later, be ready to update the space so every new room still meets today’s code.

The Portsmouth, NH homeowners’ guide to basement remodelings

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