You’re not just adding a window to your roof. You’re creating usable square footage in a space that’s currently wasted.
Most attics in older Roslyn homes weren’t designed for anything but storage. Low ceilings, no light, cramped layouts. A dormer changes that by raising the roofline and adding windows, which means you get headroom, natural light, and actual living space. That could be a bedroom, a home office, a playroom—whatever your family needs right now.
And you’re doing it without the expense of moving, the hassle of a full addition, or the months of construction that come with building out. Dormer installation typically runs between $80 and $200 per square foot depending on the type and scope, which is often far less than what you’d spend on a ground-level extension or the closing costs of selling and buying in this market.
You stay in the neighborhood you love. Your kids stay in their schools. And you finally get the space you’ve been putting off.
We’ve been handling large-scale renovations across Long Island since the early 1970s. Dormers, extensions, full kitchen and bathroom remodels—we’ve built them in nearly every style of home Roslyn has to offer.
What sets us apart isn’t just experience. It’s how we treat the process. You’ll talk to Ray or his son directly, not a sales team. When you call, someone answers—even at 3 a.m. if a pipe freezes or something goes wrong. We keep job sites clean, crews professional, and communication constant.
Roslyn homeowners deal with older housing stock, tight lots, and high expectations. We get that. We’ve worked in this area long enough to know what matters here: quality work, clear timelines, and zero runaround.
First, we come out and look at your attic. Not every roof can support every type of dormer, so we assess the structure, the pitch, and what you’re trying to accomplish. Then we talk through your options—gable dormer, shed dormer, or a full Cape Cod-style addition—and what each one costs and delivers.
Once you’re clear on the plan, we handle permits if needed. Most municipalities in Nassau County treat dormers as alterations, which usually means approval in 10 to 15 business days. Then we schedule the work.
During construction, we open up the roof, frame the dormer, install windows, insulate, and finish the interior. Depending on size and complexity, most projects take between four and twelve weeks. We clean up every day, keep you updated throughout, and make sure the new space integrates with the rest of your home—not just structurally, but visually.
When we’re done, you’ve got a finished room. Not an unfinished attic with potential. A room you can use the day we hand over the keys.
Ready to get started?
A dormer isn’t just carpentry. It’s roofing, framing, insulation, electrical, drywall, flooring, and finish work. We handle all of it.
That includes removing the existing roof section, building the dormer structure, installing new windows that match your home’s style, weatherproofing and flashing, insulating to current code, and finishing the interior so it’s move-in ready. If you want the space to function as a bedroom, we’ll add closets and ensure egress requirements are met. If it’s an office, we’ll run the outlets and lighting where you need them.
In Roslyn, where most homes were built in the 1950s and early 1960s, we often find surprises once we open things up—old wiring, undersized framing, or structural issues that need addressing. We budget for that. It’s why we recommend setting aside 15 to 20 percent as a contingency, especially on older homes. But we don’t surprise you with it halfway through. If we find something, we talk to you before we move forward.
And because we’re a general contractor, if the project touches your roof and you’ve been meaning to replace shingles or add siding, we can handle that too—all in one job, one timeline, one point of contact.
Dormer costs in Roslyn typically range from $80 to $200 per square foot, depending on the type and complexity. A shed dormer, which runs along the length of the roof, usually falls between $75 and $120 per square foot. A gable dormer, which projects out from the roof, runs closer to $110 to $150 per square foot.
The total price depends on size, how much interior finishing you want, whether we’re adding a bathroom or closet, and what we find once we open up the structure. Older homes sometimes need additional framing or updated electrical, which can add to the scope.
We give you a detailed estimate upfront and recommend budgeting an extra 15 to 20 percent for contingencies. That way, if we run into something unexpected, the project doesn’t stall while you scramble for funding.
Yes. Adding livable square footage almost always increases home value, especially in a market like Roslyn where inventory is tight and buyers are looking for move-in-ready homes with flexible layouts.
A dormer adds both functional space and curb appeal. It makes your home look larger from the street and gives buyers more options—extra bedroom, home office, playroom. In a neighborhood where the median home value is over $620,000, that kind of flexibility matters.
You’re also making your home more competitive if you ever decide to sell. Buyers in this area want space, light, and character. A well-designed dormer delivers all three without the cost or disruption of a full second-story addition.
Most dormer projects take between four and twelve weeks, depending on size, scope, and weather. That includes permitting, construction, and interior finishing.
Permitting usually takes 10 to 15 business days in Nassau County. Once we start construction, the framing and exterior work might take two to four weeks. Interior finishing—drywall, flooring, paint, trim—adds another few weeks depending on what you want done.
Winter weather can slow things down, especially on Long Island where frozen conditions affect roofing work. If we’re working during colder months, we plan around that and keep you updated on any delays. But once we’re on site, we work efficiently and keep the job moving so you’re not living in a construction zone longer than necessary.
In most cases, yes. Roslyn and the surrounding Nassau County area require permits for structural changes like dormers, even though they’re typically classified as alterations rather than new construction.
The good news is that permitting for dormers usually moves faster than permits for full additions or new builds. Most municipalities approve dormer plans within 10 to 15 business days as long as the design meets code and doesn’t violate setback or height restrictions.
We handle the permit process for you. That means pulling the paperwork, submitting plans, coordinating inspections, and making sure everything is up to code before, during, and after construction. You don’t have to deal with the town or chase down approvals.
A shed dormer runs horizontally along the roof and has a single sloped plane. It’s the most cost-effective option and gives you the most interior space because it extends across a larger section of the roofline. If you’re trying to turn your entire attic into usable square footage, a shed dormer usually makes the most sense.
A gable dormer projects out from the roof with a peaked front, like a small house sitting on top of your roofline. It adds less interior space than a shed dormer, but it creates more architectural interest and can boost curb appeal. Gable dormers work well if you only need to add one room—like a bedroom or office—and want the exterior to have more character.
Both options add light and headroom. The choice comes down to how much space you need, what your budget allows, and what fits the style of your home. We walk you through both during the estimate so you can see exactly what you’re getting.
Absolutely. That’s one of the most common reasons homeowners in Roslyn add a dormer—they need another bedroom or a dedicated bathroom upstairs, and the attic is the only place left to build.
Adding a bedroom means we’ll frame out closet space and make sure the room meets egress requirements, which usually involves a window large enough to serve as an emergency exit. If you’re adding a bathroom, we’ll run plumbing and ventilation, which can add complexity depending on where your existing lines are, but it’s all manageable.
The dormer gives you the height and layout flexibility to make these rooms functional, not cramped. And because we’re handling the whole project—framing, mechanical, finishing—you’re not coordinating between multiple contractors or waiting on different schedules. It’s one job, start to finish.
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