Home Additions & Extensions in NYC
Home additions and extensions across Long Island, Staten Island, and northern New Jersey, delivered by a Newark-based design-build firm with 10+ years on residential additions. Dormers, second-story additions, bump-outs, in-law suites, and sun rooms — designed, permitted, framed, and finished by one team.
[License #] · 2-year workmanship warranty · 5.0 ★ Google · Licensed, Insured & Bonded · 10+ years.
Schedule a free consultation — in person or by video. Call (862) 430-3655.
Where home additions actually happen
Most residential additions in the NYC metro happen on Long Island and in northern New Jersey — that’s where the single-family housing stock with the lot space, zoning, and existing footprint to support an addition lives. Manhattan, Brooklyn, and Queens additions are rare; the housing there is mostly multi-family or attached, so what looks like an “addition” is usually a roof-deck buildout, a terrace enclosure, or a rear townhouse extension. We do all three, but the bulk of the addition portfolio is suburban — Nassau, Suffolk, Bergen, Essex, Union, Hudson, Morris.
Addition services we offer
Dormers
Shed dormers, gable dormers, and eyebrow dormers — usually built to convert unfinished attic space into a bedroom, master suite, or home office. Dormers add habitable square footage without expanding the home’s footprint, which often means a faster zoning path. Most dormer builds run 3 to 5 months.
Second-story additions
Full or partial. We open the existing roof, frame the new floor system on top of the existing first-floor walls (sometimes requiring foundation reinforcement), build the new walls and roof, and tie the existing stairwell into the new level. Substantial scope, requires temporary relocation while the roof is off. 6 to 9 months.
Bump-outs
Single-story extensions, typically off a kitchen, family room, or master bedroom. The smallest addition type — sometimes only 8 to 12 feet of new footprint — but it can make the difference between a usable kitchen and a cramped one. 3 to 5 months.
In-law suites and accessory dwelling units
A bedroom, bathroom, kitchenette, and separate living area, often with a private entrance. Permitted as a separate use under most NJ and Long Island zoning ordinances. We coordinate with the township on use restrictions, parking requirements, and meter separations.
Sun rooms and three-season rooms
Insulated sun rooms with operable windows, ceiling fans, and integrated heating/cooling for year-round use. Three-season rooms with screened openings for warmer months. Built on existing decks or as new slabs, depending on lot and code.
Garage additions and conversions
New attached garages, detached garages, and conversion of existing garages into habitable space. Conversions usually require zoning review and HVAC integration.
Townhouse rear extensions (Brooklyn / Manhattan)
Where they apply: rear-yard extensions on brownstones and townhouses, typically to expand a kitchen or add a sunroom. Subject to landmarks review in some districts and full DOB filing.
How an addition runs
Additions take longer than interior remodels because the design and permitting phases are heavier. The build sequence is also weather-dependent.
- Free consultation. We walk the property, photograph the existing house from every angle, talk through what you want, and confirm whether the addition is feasible given lot setbacks, zoning, and roof line.
- Design and permitting. Architectural drawings, structural engineering, township submission, zoning review (and variance application if required). 8 to 16 weeks across most NJ and Long Island municipalities. We file and follow up; you don’t sit through the township meetings unless your lot needs a variance hearing.
- Build. Foundation, framing, roofing, exterior, MEP rough-in, insulation, drywall, finishes. Trusted licensed plumbers — long-term partners we’ve worked with for years — handle plumbing rough-in for the new bathrooms or kitchens. In-house tile and stone setters handle finished surfaces.
- Walk-through and warranty. Punch list, deep clean, 2-year workmanship warranty, manufacturer warranty pass-through.
Service areas
Additions are most common in our suburban service zones:
- Long Island home remodeling (Nassau, parts of Suffolk)
- Staten Island home remodeling
- Yonkers home remodeling
- Newark NJ home remodeling
- Elizabeth NJ home remodeling
We also do additions in Bergen, Hudson, Essex, Union, and Morris counties — Edison, Paterson, Morristown, and similar. The five-borough density doesn’t support typical addition work as often, but we’ll do rear extensions and roof-deck builds where they’re permitted.
Featured addition projects
- Second-story addition with master suite, Long Island. Existing one-story ranch raised to two-story; new master bedroom, master bath, two secondary bedrooms, and a laundry on the new level. Roof off for 6 weeks. Total build 7.5 months.
- Shed dormer with bedroom and bath, Long Island. Unfinished attic converted to a teenage bedroom and a full bath. Existing roof opened on the rear elevation; siding and shingle profile matched to the original. 4 months.
- Family-room bump-out, NJ. 14-foot extension off the back of a colonial; new family room with a vaulted ceiling, a stone fireplace, and a slider to a new deck. Foundation poured in week 3, occupied in month 4.
Why homeowners choose LM Pro for additions
- Architects and engineers we’ve worked with for years. Design-phase coordination is fast because the team already speaks the same language.
- Township permitting handled. We’ve filed in most NJ municipalities and Long Island townships our service area covers.
- Trusted licensed plumbers — long-term partners we’ve worked with for years. New bathrooms and kitchens in additions get the same plumbing standards as a primary-bath remodel.
- Tie-in detailing. Siding, shingles, trim profiles, hardwood species, paint sheen — matched, not approximated.
- One project lead through design and build. The person who took the consultation is the person you text in month seven.
- Insured and bonded. Bond covers NJ HIC compliance specifically; NY work runs under separate coverage.
Frequently asked questions
How long does a home addition take?
Most home additions run 4 to 9 months on the build, plus 8 to 16 weeks of permitting and design work before any framing starts. A bump-out family room is the fastest at 3 to 5 months. A full second-story addition or a substantial dormer build is closer to 7 to 9 months. Permits, engineering review, and weather drive most of the variance.
What types of additions do you build?
Dormers (shed, gable, eyebrow), second-story additions (full or partial), single-story bump-outs (kitchen, family room, mudroom), in-law suites, sun rooms, and integrated garage additions. We don't do prefabricated additions or modular box add-ons — every addition we build is stick-framed on site to match the existing house's structure and finishes.
Where do you do home additions geographically?
Most of our addition work is on Long Island (Nassau and parts of Suffolk), Staten Island, and northern New Jersey — Bergen, Essex, Hudson, Union, and Morris counties. Manhattan, Brooklyn, and Queens additions are rare because the housing stock is mostly multi-family or attached — additions there typically mean a roof-deck, terrace enclosure, or rear extension on a townhouse, all of which we do but they're not the bulk of the addition portfolio.
Do you handle the architectural drawings and engineering?
Yes. We work with structural engineers and licensed architects we've used on multiple projects. They produce the construction drawings, run the structural calculations, and stamp the plans for filing. The architect and engineer fees are line items on the proposal, not hidden in our number — you see exactly what you're paying for the design phase.
What permits are required for a home addition?
On Long Island and in NJ, you'll need a building permit from the local township or village, a zoning approval if the addition extends the home's footprint, and inspections at framing, rough-in (plumbing, electrical, HVAC), and final completion. Some townships require a survey, a variance hearing, or a wetlands review depending on the lot. We file every permit and manage every inspection. Permitting timelines run 6 to 14 weeks across most NJ and Long Island municipalities.
Can you tie a new addition into the existing roof, siding, and interior?
Yes — and matching the existing finish is the design detail that separates a good addition from one that looks bolted-on. We match siding profiles and stains, roof pitch and shingle color, interior trim profiles, hardwood species and stain, and paint sheen. Where the original material is discontinued, we identify the closest match and frame the transition naturally.
Do additions usually require us to move out?
It depends on the scope. A bump-out off a kitchen or family room can usually be built while you live in the home, with dust barriers between the new construction and the existing space. A full second-story addition opens the existing roof to weather — most homeowners find a temporary place to stay for the 4 to 8 weeks the roof is off. We sequence the build to minimize that window.
Will an addition increase my property taxes?
Yes. Adding habitable square footage to your home will trigger a re-assessment by the local tax assessor — that's universal across NJ and NY. We can give you a rough estimate of the assessed-value increase based on comparable additions in your township, but the final number comes from the assessor's office. Plan for it as a real line in the post-build budget.
Reviews
5.0 ★ on Google. 5.0 ★ on Yelp. Addition reviews on the reviews page tend to focus on permit handling, schedule discipline through long timelines, and finish-matching at the tie-in seams.
Ready to start your addition?
Call (862) 430-3655 or schedule a free consultation. For additions, an in-person visit is best — we need to see the existing house, the lot, and the roof line before the design phase begins.