Home additions that look like they were always part of the house.

Most additions on the North Shore take one of a few shapes. A rear or side addition puts a family room, a bigger kitchen or a mudroom on the ground floor. A primary suite adds a bedroom, bath and closet, either on the ground for one-floor living or over an existing first floor. A second story turns a Cape or a ranch into a full two-story house without giving up the yard. A bump-out finds a few feet for a kitchen or bath without new rooflines. Garage wings with rooms above round out the list.

Recent ones close to home: a second level and a whole-house renovation in West Peabody, a rear addition and a second-floor primary suite in Beverly, and a 12×12 addition in Peabody, built from the foundation to the tie-in. A mudroom and garage addition with living space above is underway in Essex.

If the new space is meant for a parent or an adult child, with its own kitchen and entrance, it may be an accessory dwelling unit under Massachusetts law, which changes the rules. See ADUs and in-law suites, and our comparison of an ADU vs. an addition.

Before anything is drawn we pull the zoning for your lot: the district, the setbacks from each property line, height limits, and whatever the town uses to cap size, whether that's lot coverage, open space or floor area ratio. Many older North Shore houses already sit closer to a line than today's bylaw allows. That doesn't rule out an addition, but it can mean a finding for a pre-existing nonconforming structure under M.G.L. c.40A s.6, or a variance from the zoning board of appeals.

Zoning relief means public notice, a hearing and an appeal period before a building permit can issue, so it belongs at the front of the schedule, not the middle. Overlays matter too. In a local historic district, the historic district commission has to issue a certificate before a building permit for exterior changes. Work within 100 feet of a wetland goes to the conservation commission. A floodplain changes how, and how high, you build. Rules differ town to town, so we check with your town's building, zoning and conservation staff before we design around an assumption.

An addition is only as good as what it sits on. Many North Shore lots have granite ledge close to the surface, and some are wet clay that holds water against a foundation. Ledge may need to be removed or the footings pinned to the rock, and a structural engineer should make that call. Clay calls for drainage and sometimes wider footings. The footings for an attached addition go below the frost depth the building code sets, so the new part of the house moves with the old part, not against it.

Second stories are a different test. The existing walls, footings and foundation now carry another full floor and a roof. We open up enough to see what is there, and the engineer sizes beams, posts and any foundation work. Fieldstone and brick foundations are common under antique houses and get judged on their own terms.

The difference between an addition that belongs and one that looks bolted on is mostly in the roof and the skin. We start from the existing roof pitches, eave heights and overhangs, and design the new roof to meet them cleanly, with valleys and flashing that shed water and don't hold snow where ice dams form. Where rooflines can't line up, a lower connector often reads better than forcing them.

On the outside we match what is there: the clapboard exposure, the width of the corner boards, the profile of the window casings and sills, white cedar shingles that will weather to match. Inside, the seams are floor heights that don't quite line up, old plaster meeting new drywall, and heat and wiring that have to be extended. We plan those transitions on the drawings so they are decided before demolition, not on the day.

Massachusetts towns are on one of three energy codes: Base, Stretch or Specialized. In Stretch and Specialized towns, an addition of more than 1,000 sq ft of conditioned space, or one that more than doubles the house's existing conditioned area, means the combined house has to meet a HERS rating target for additions, and a HERS rating includes a blower-door test. Multiple additions to the same house count together, and only conditioned space counts. Smaller additions follow the code's prescriptive insulation, window and mechanical requirements.

Per the state's list as of June 2026, Peabody, Marblehead and Hamilton are Stretch towns; Salem, Swampscott, Beverly, Newburyport and Andover are Specialized; Danvers, Lynnfield, Middleton and Essex are on the Base code. Towns change tiers, so we confirm yours. More in our guide to the stretch code and additions.

On septic, bedrooms set the design flow: Title 5 counts 110 gallons per day per bedroom. A new bedroom raises the design flow, and Title 5 requires a system inspection before an expansion like that. Any system not built to the 1995 code is considered nonconforming, and the board of health decides what the system needs to carry the new count. Find out before you design the fourth bedroom. See Title 5 and adding bedrooms.

An addition can usually be built while you live in the house. The new space goes up outside the existing walls first. We cut the opening into the house as late as we can, behind dust walls, and plan around the kitchen, baths and bedrooms you need, so the disruption inside is as short as we can make it.

You get a private online portal with the schedule, daily job-site photos, selections and financials, plus a "today at your home" card, and decisions are kept in email so nothing depends on anyone's memory. Bill manages the project and Howie leads the field. When something comes up, like rot behind old siding or a joist someone notched decades ago, you get photos and options before anything is decided, and any change is a written change order.