Basement Finishing in Durham, NH

In a town where housing is tight the way it is around a university, an unfinished basement is square footage nobody is using. A finished one is a bedroom to rent, a home office, or room for a kid back from school for the summer, and it happens without adding an inch to the footprint of the house.

What it costs to finish a basement in Durham

Square footage drives most of it, along with whether plumbing for a bathroom is part of the scope and how much wiring and HVAC work has to start from nothing. A small single-room job can wrap in about a month; a full basement with a bathroom can run closer to six. Unlike a lot of contractors, we do not split the job between subs, one crew sees it from the first stud to the final walkthrough, and we handle the town permit ourselves.

Before anything gets framed

Before a single stud goes up, we want to know whether the space has ever taken on water. If it has, that gets solved first, full stop, since drywall over a wall that could still let water in only buys you a few years before the same problem reappears behind a much more expensive finish. A basement with a clean history skips straight to the framing conversation.

Where a bedroom is part of the plan, a code-compliant egress window comes with it. We confirm the exact requirement with your town before framing starts rather than guess.

What goes into the build

Framed walls sit off the foundation instead of nailed flat against it, with pressure-treated bottom plates and insulation that will not hold water against the wall if a small leak ever happens. It is built to survive being a basement, not just to look finished on day one.

Designing for a tenant who is not the owner

When the person who will live in the finished space is not the person paying for it, we build to a different standard than a typical owner-occupied job: durable flooring that tolerates furniture moves between tenants, paint and finishes that hold up to normal wear rather than delicate wear, and layouts that work for a range of occupants rather than one specific household’s taste.

What adding a legal bedroom actually requires

• A code-compliant egress window, sized and placed to meet the current requirement, confirmed with your town before we frame
• Adequate ceiling height throughout the room, not just at the center
• Heat source, most towns require it to count as a habitable room
• Smoke and carbon monoxide detection per current code

We confirm the specifics with your town rather than build to a generic standard that might not match Durham’s actual requirements.

Building for turnover, not just for now

A basement finished for a family that owns the house and a basement finished as a rental unit get built differently, even with the same square footage and the same budget. In a rental, flooring and paint need to survive a new tenant every year or two without a full redo each time, which is why 603 leans toward luxury vinyl plank over carpet in these units specifically, and toward paint and trim that a property manager can touch up in an afternoon rather than a full repaint. None of that changes what is required for the space to be legal. It changes what still looks right after the fifth move-out.

Frequently asked questions

What a recent customer said

We had a wonderful experience working with 603 to have our basement finished. From the initial walk down with Chris to through the project execution phase. Ray and his crew were fantastic, communicative, hardworking, and great attention to detail.

Kristen Youcis, 5 stars, Google review

Review quoted verbatim, public Google review.