Top-rated basement remodelers.

Get matched with top basement remodelers in Portsmouth, NH

Enter your zip and get matched with up to 3 pros

Matching on HomeAdvisor

Share some details icon
Share some details about your home project.
Match with local pros icon
Within moments, match with highly-rated local pros.
Compare quotes icon
Compare quotes and choose the best pro for the job.

Find Basement remodelers in Portsmouth

Avatar for MMP Construction Inc
MMP Construction Inc
4.6(
222
)
Basement - Remodel

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2004

Free estimates

Emergency services offered

"When we started our plan of remodeling, the first thing we did was the complete roof replacement including kitchen vent & duct pipe installation to the roof, and new installation of attic ventilation. MMP did not only completed it just as agreed but also very efficiently. The crews were friendly, professional, and careful. The jobs were carefully managed and implemented effectively. I was impressed by Matt, who is the manager, and he does an outstanding job in managing the crews and the progress of the situation, and the communication was clear and always to the point. We then moved to initiate a search for a contractor of two bathrooms remodeling after completing the roof and attic vent, MMP was one of the many candidates. Matt has had not only the best idea and proposals but also shown an impressive & professional sense of evaluating the project accurately, including the possible structural modification as well as a competitive estimate of the cost of the build. His proposal included a rebuild of a wall of the bathroom to expand another one adjacent to it. Matt accepted to use my schematic design image (made with a software tool) and a spreadsheet list of the fixtures that I created - as many as fifty items including TOTO, Grohe, American Standard, Panasonic, and IKEA - to start the job (later changed some of them due to local plumbing code compliance) After beginning the bathroom remodel project, Matt shared what jobs will be done with us timely and efficiently via text so that we feel comfortable enough in knowing what is going on while living in the house of dust & noise from remodeling. The crews, Zen and Mark, were very courteous, extensively experienced, reliable, and friendly with excellent communication, sometimes with songs of 80s rock music. They ask me when more precise specifications are needed and notified me when they feel advance notifications are required. When a change is necessary due to inspection, they informed me and clarified what and why. I have never felt uncomfortable in living together with the remodel job which has lasted over four months. The completed two bathrooms were stunning, just as I imagined. Matt, Zen, and Mark have proved their strong & thoughtful expertise and lived up with my request patiently until completion. Great job. A home remodeling project cannot be successful without having a trusted partner, and my experience with MMP has led me to be glad to share my confidence that MMP has a credential to become your reliable partner to manage a construction project together."
Additional Photos
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+154

Recommended by89%of homeowners
Avatar for NH Projects LLC
NH Projects LLC
5.0(
20
)
Basement - Remodel

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2021

Free estimates

Customers say: Quick response

"Lenny and Nick went above my expectations! I told them what I wanted, Nick sketched out a plan, and it was perfect! My basement is absolutely beautiful! They were reliable, prompt, and told me everything that was going on! I would highly recommend this company for any remodel! Bravo guys!"
Our Work
Our Work
Our Work
Our Work
Our Work

+8

Response time5 hrs
Response rate87%
Recommended by84%of homeowners
Avatar for IDEAL SOLUTIONS LLC
IDEAL SOLUTIONS LLC
4.8(
13
)
Basement - Remodel

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."
17 neighbors recently requested a quote
Recommended by66%of homeowners
Avatar for Horsman Builders
Horsman Builders
4.3(
23
)
Basement - Remodel

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 time7 hrs
Response rate100%
2 neighbors recently requested a quote
Avatar for Benchmark Home Improvements
Benchmark Home Improvements
4.8(
143
)
Basement - Remodel

Serving Portsmouth, NH and surrounding areas

Approved

In business since 1997

Free estimates

Credit card accepted

"We are so happy that we hired Benchmark to remodel our kitchen! Lee and Ian were professional and knowledgeable, from beginning to end. We were very impressed with their attention to detail. They made our 1980's dingy, dark kitchen look amazing with beautiful white cabinets and granite countertops. We love it! I highly recommend Benchmark and will recommend them to my family and friends. Thank you, Lee and Ian! Sallie and Don M."
BBB torch award for 2018!
BBB torch award for 2018!
BBB torch award for 2018!
BBB torch award for 2018!
BBB torch award for 2018!

+18

Response time2 days
5 neighbors recently requested a quote
Recommended by100%of homeowners
Avatar for The Hurlburt Group, LLC
The Hurlburt Group, LLC
4.4(
35
)
Basement - Remodel

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2007

Free estimates

Small jobs welcome

"This was our 3rd project with the company. 1st was finishing the basement, which included a bathroom with a shower. 2nd - half bath remodel with an accent stone wall. And the most recent- master bath remodel which included adding a soaking tub and converting a linen closet into a shower. Dave, the owner, was very patient with me when I kept changing my mind regarding the design and materials till the very last moment when everything was already demolished. When we could not find the linen tower i envisioned , Dave custom built it! As a result, we have a beautiful spa bathroom with gray stone and wood accents. For all 3 projects we worked with Steve who does a great job! We are very pleased with the quality of work, work ethics and communication. We will definitely be using Dave again for our next project. Highly recommend!"
basement subfloor
garage door
new beam header
garage door
closet

+77

Response time3 days
Response rate88%
11 neighbors recently requested a quote
Avatar for DCL Construction
DCL Construction
5.0(
9
)
Basement - Remodel

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
2 neighbors recently requested a quote
Recommended by66%of homeowners
JDL Building & Remodeling of New England, LLC
4.9(
12
)
Basement - Remodel

Serving Portsmouth, NH and surrounding areas

Approved

In business since 2001

Free estimates

Warranties offered

\nWe are a full service General Contracting Company who can manage your project from conception to completion. This includes design, permitting and construction. Athough we specialize in providing turn-key services, we can also be contracted to perform any trade service or scope or work. \n \nJason Lajeunesse, owner of JDL Building & Remodeling of New England, LLC, is a second generation building contactor with over 10 years of general contracting and trade experience. This experience and our strong Estimating and Project Planning Skills allow us to deliver our projects on budget and schedule. \n \n

North Andover MA Basement Finish Project
Detached 2 Car garage with walkup
North Andover MA Basement Finish Project
Detached 2 Car garage with walkup
North Andover MA Basement Finish Project

+5

Recommended by100%of homeowners
...
Showing 1-10 of 203
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.