Skylight Installation and Replacement in Derry, NH
A lot of Derry roofs went up in the same twenty-year stretch, which means a lot of skylights up there are the same age too. If your kitchen or upstairs bath has a cloudy acrylic bubble that fogs up from the inside every winter, it was probably installed around the same time as three of your neighbors’ units, and it’s probably done for the same reasons theirs is.
Skylight Installation and Replacement in Derry
There are two different jobs on this page and they call for two different conversations. The first is a straight swap: an existing skylight has failed and you want a modern unit in that same opening, almost always timed with a roof replacement because the roof is already open and the flashing is already coming apart. The second is a new cut-in: no skylight exists yet, and you want one, usually to bring light into a dark north-facing bedroom, a stairwell, or an add-on that never got a window where it needed one.
Both are legitimate projects and both are worth doing right, but they are not the same decision. A replacement is largely a known quantity – we know the opening size, we know the roof structure around it, and the labor is mostly removal and reinstallation. A new cut-in means opening framing that has never been touched, checking rafter spacing, and making sure the shaft down to the ceiling is actually feasible before anyone picks a skylight model. We’ll tell you straight which one you’re looking at once we’re on the roof.
Deck-mounted
units fasten straight to the roof deck and use a matched step-flashing kit. This is what goes on most pitched roofs now. It sits low, looks clean and handles snow well.
Curb-mounted
units sit on a raised wood frame built on the roof. They are the right call on low-slope sections, generally below about 3 in 12, and a lot of older installs already have them.
Fixed
units let in light and nothing else. Fine over a high cathedral ceiling you will never reach.
Manual or electric venting
units open to let heat and steam out. They earn their keep in kitchens and bathrooms.
Solar-powered venting
units run off a small panel, need no wiring to the house, and close on their own when the rain sensor gets wet.
What Derry roofs and homes are working with
Derry, along with Londonderry, Windham, and Salem NH, built out heavily from the late 1970s through the 1990s, and a huge share of that housing stock is now hitting first-replacement age on everything at once – roofs, windows, and skylights included. If your subdivision went up in one of those waves, there’s a decent chance the acrylic dome unit over your kitchen or bath is original to the house, and acrylic domes from that era rarely make it past twenty-five years without yellowing, crazing, or leaking at the seal.
What varies from house to house across this territory is roof pitch and how much of the attic is finished space. Colonials and capes with a simple gable roof are usually the easiest cut-ins – straight rafter bays, no valleys to work around. Contemporary and raised-ranch designs with cathedral ceilings in the great room are a different animal, because there’s often no attic buffer at all between the roof deck and the finished ceiling below, which changes both the install and the ventilation math. Tree cover matters here too – a lot of Derry lots back up to woods, and heavy shade over a north-facing slope means more moss, more moisture sitting on the shingles around an old curb, and a faster path to a soft deck under the flashing.
How we assess it
We don’t quote a skylight over the phone. Derek or one of the crew gets on the roof and looks at the flashing detail first – step flashing, head flashing, and the counterflashing where it ties into the curb, because that’s where nearly every skylight leak actually starts. We check the shingle course around the opening for cracking or granule loss, pull back a corner if we need to, and look at the deck itself for soft spots or staining that would tell us water has already been getting in.
From inside, we look at the underside of the opening for water staining on the drywall or the shaft, and we check whether the attic or roof cavity around it is vented the way it should be. A skylight installed without adequate ridge or soffit airflow around it is one of the more common reasons units fog and rot early, even when the unit itself is fine. We tell you what we see before we talk about what to do about it, not after.
What the job involves
Replacement
We strip the shingles around the unit, pull the old skylight and flashing, repair the deck at the opening if it needs it, and set the new unit. Ice and water shield wraps up the sides and across the top, the step-flashing kit goes on, and we shingle back in. If the new unit matches the rough opening, the interior usually stays as it is. On a full roof replacement in Derry, all of this fits inside the reroof. The shingles are already off, the deck is exposed, and the new underlayment and flashing tie in as one system.
New cut-in
We lay out the opening from inside and out, cut the deck, and frame headers between the rafters. Ventilation gets rerouted so the bays above and below the opening still breathe. Then the unit, ice and water shield, flashing and shingles. Inside, a new opening means a light shaft through the attic, drywall and paint. That interior work is part of the conversation at the estimate, and we settle who handles what before anything is scheduled.
For a replacement, the work is removal of the old unit, inspection and repair of the decking and flashing underneath, and installation of the new skylight with fresh step flashing, ice and water shield around the curb, and a proper seal at the head and sides. If the reroof is happening at the same time, this is folded straight into that job – the roof is already stripped down to deck in that area, so there’s no double labor tearing into finished shingles twice.
For a new cut-in, we’re framing a new opening in the rafters, sizing it to the unit, and running a light shaft down to the ceiling below. That means coordination with drywall and paint work inside the house, which is part of the conversation when we scope the job but isn’t something we’re promising to handle end to end – we’ll talk through who does what before anything gets cut.
Unit choice matters more than people expect. Curb-mounted skylights sit on a raised wood curb built on the roof deck and are the standard for most reroof-timed replacements. Deck-mounted units sit lower, flush to the roofline, and tend to show up more on newer construction or lower-slope sections. Fixed units are simplest and cheapest. Venting units open manually or electrically for airflow. Solar-powered venting units run off a small panel built into the frame and don’t need household wiring, which is often the easiest upgrade path when you’re already replacing a fixed unit anyway.
What it costs
A straight replacement, unit for unit, during a reroof generally runs {PRICE_LOW} to {PRICE_HIGH}. Doing that same swap on its own, outside a reroof, costs more, because you’re paying for a standalone tear-off and re-flash of just that section rather than sharing labor with the rest of the roof. That’s the single biggest cost lever on this page – if your roof is due anyway, timing the skylight to the reroof is the cheaper path almost every time.
A new cut-in costs more than a replacement because you’re paying for framing work, a light shaft, and interior finish coordination on top of the roofing and unit itself. What moves the number within either category: unit size and whether it’s fixed, venting, or solar-powered venting, curb-mounted versus deck-mounted, roof pitch and how hard the roof is to access, and whether we find soft or rotted decking once the old unit comes off – that’s a repair we’ll flag and price separately, not something we fold in silently.
How long it takes
A replacement timed with a reroof adds very little to the overall schedule, usually well under a day once the crew is already working that section of roof. A standalone replacement on an otherwise sound roof is typically a single day. A new cut-in takes longer because of the framing and shaft work – plan on a day or two for the roofing side alone, with interior finish work following on its own timeline once the opening is closed in and weathertight.
Get an estimate
If you’re not sure whether your unit needs replacing or your dark upstairs room is actually a good candidate for a cut-in, get someone on the roof before you decide anything. Call {PHONE} and we’ll set up a time to look at it and give you a straight answer on what it is and what your options are.
Can you replace my skylight without redoing the whole roof?
Yes. A standalone replacement is common when the roof itself still has years left but the skylight unit has failed. It costs more than a swap timed with a full reroof since it's a separate tear-off and re-flash of just that section, but it's a normal job on its own.
Is it cheaper to replace a skylight during a reroof?
Almost always. When the roof is already stripped down to the deck around the skylight, there's no duplicate labor tearing into finished shingles a second time. If your roof is nearing replacement age anyway, timing the two together is the more economical route.
What's the difference between curb-mounted and deck-mounted skylights?
A curb-mounted skylight sits on a raised wood curb built up on the roof deck, which is the standard setup for most reroof-timed replacements. A deck-mounted unit sits flush to the roofline with a lower profile, more common on newer construction.
Do you handle the drywall and light shaft for a new skylight?
The interior finish work is part of the conversation when we scope a new cut-in, but it isn't something we're promising to handle start to finish. We'll talk through who's doing the interior work before the job starts.
Does Couture's work in Derry, NH, or just Massachusetts?
How do I know if I need a solar-powered venting skylight instead of a fixed unit?
Ready to talk it through?
Reach out and let us know if this is a straightforward replacement or a new skylight you’re considering for a Derry home. Share the room, roof pitch if you know it, and how the current skylight has been performing. We’ll arrange a visit to check the roof and attic space, then walk through what makes sense for your house.