Reflashing, resealing and replacing skylights whose curbs and seals have aged, plus new skylight openings on older roofs.
Fastest: call (833) 751-2102. Or send this and we call you back.
Skylights leak at the frame, curb and flashing, or the glazing seal has failed, much more often than through the glass. Newton Roofing connects Newton and Middlesex County callers with an independent roofer who finds the real source, reflashes or replaces the unit, and installs new skylights on pitched roofs.
A skylight is a hole cut in the roof and then filled with a window, so the whole job rests on the ring of flashing around it. The glass is rarely the weak point. The weak points are the corners of the frame, the lower edge where water collects, the seal between the glass and the frame, and the counter-flashing at the sides where shingles meet the curb.
Winter makes it harder. In a snowy stretch, drifted snow can sit against a skylight for days, and the water from that pile does not run off quickly. It soaks the curb, creeps under the flashing and finds old caulk. Some skylights also cause stains that are not leaks at all, because cold glass collects condensation, which drips off the frame and looks like water from outside.
If you can see a stain or drip around a skylight, call (833) 751-2102. Say whether it appears in rain, after snow melts or on cold mornings with no precipitation at all. The line puts you through to an independent roofer who serves your town; the roofer inspects the unit and does the work.
Never stand or lean on a skylight, and do not walk a snowy roof to find one that is buried; glazing can break under a person's weight and the fall is serious. Keep a pan under a drip, switch off any light fixture the water touches and call an electrician if wiring is wet.
Skylight work is priced by what has failed and how big the unit is. A reflash and a full replacement are very different jobs. No local price is published for either, so this page carries no dollar figures.
| Job | Typical range | What it includes |
|---|---|---|
| Resealing or reflashing an existing skylight | Quoted on site | Depends on roof pitch, material and how many sides need work |
| Replacing a skylight with a new unit and flashing kit | Priced by unit size and type | Includes removing the old frame and shingling in the new one |
| Adding a new skylight where there is none | Priced by size, framing and the roof opening | May involve a cut in a rafter and a new light shaft |
| Repairing wet drywall and insulation in the shaft | Added after the leak is stopped | Often done by a separate trade |
These notes describe what moves a quote. The roofer confirms scope and a written price on site, before any work starts.
These sit directly on the roof deck with a flashing kit made for the unit, and they are common on shingle roofs. Because they sit low on the roof, snow can drift against them. A kit that does not match the roofing material or the unit is a leading cause of a skylight that was installed once and has leaked since.
A raised wooden curb is built on the roof and the skylight sits on top, a common detail on low-slope and flat roofs. Water has to be carried around the curb, so the roofer must flash it like a small chimney, and the curb itself should be checked for rot.
Fixed units do not open, venting units do and tubular units are small domes that carry light through a tube. Each has different seals and different failure points. Replacing a venting unit also means checking the opening hardware or any powered mechanism.
Most skylight installation and leak repair calls are scheduled the same day when a technician is free, and you approve the price before any work starts.
Condensation shows up on cold, dry days as moisture on the glass and frame, often dripping from the lower edge. A leak shows up during or after rain or melting snow and leaves a stain that grows. A roofer separates the two by timing and by looking at the flashing and glazing.
Skylights are colder than the rest of the ceiling, so humid indoor air condenses on them first. Bathrooms and kitchens add moisture, and a skylight in a bathroom is a good example. The remedy for condensation is more often a ventilation change than a roofing repair.
Fog trapped between the panes is a separate matter: the sealed glass unit has failed and no amount of sealant on the outside will clear it.
A snowdrift against a skylight holds water against the curb and flashing for much longer than rain does, and meltwater can run uphill under flashing that is too low. Ice that forms along the lower edge adds to it. Skylights placed low on a roof, near the eaves, are at most risk.
A skylight sitting just above the eave is also in the path of any ice dam that forms below it. Where the leak seems to come from the glass edge, check whether the roof below is also icing up, which the ice dam prevention page explains.
If snow keeps sliding or piling at the skylight, a roofer may suggest a change in flashing or a small diverter above it. Do not rake or shovel snow off a skylight yourself.
Repair makes sense if the glass and frame are sound and only the flashing or sealant failed. Replace the unit if the glazing is fogged, the frame is rotted or the skylight has leaked repeatedly. A roofer replacing the unit should also replace the surrounding flashing at the same time.
A new skylight inside old flashing is a false economy. The curb and the cuts around the opening are part of the install, and a kit made for that unit and roofing material is the point of doing it. Ask the roofer which brand and model are proposed in writing, so you can read the manufacturer's own installation notes before the work.
If you are re-roofing, skylights are usually handled in the same project, since the roofing and flashing meet there. The roof replacement page describes what happens in a tear-off.
The roofer asks when the water appears and looks at the glass and frame. Moisture on cold mornings points to condensation, while drips after rain or snow melt point to flashing or the frame.
On the roof, the roofer checks the flashing on all four sides, the seal around the glass and the condition of nearby shingles. From inside, the light shaft is checked for stains and the framing for dampness.
If the skylight itself is in good shape, the surrounding shingles and flashing are lifted, rebuilt in the right order and sealed. This often cures a leak without replacing the unit.
If the frame is rotted, the glass is fogged or the unit has simply aged out, the skylight is replaced with a new one and a matching flashing kit rather than patched around the old frame.
Wet drywall and insulation in the light shaft should be checked and dried. The roofer tells you what was found, what was fixed and which parts need a drywall or paint trade afterward.
Cape-style and ranch houses are the typical mid-century stock in Needham and Dedham, and where an upstairs room is finished under the roof slope, a skylight is one way to bring light into it. Roofs of that age are often on a second or third set of shingles, so a skylight that was installed on an earlier roof may have flashing from a different era than the shingles around it.
On older Newton houses with additions, dormers and several roof planes, a skylight can end up near a valley or a wall line, which doubles the flashing in a small area. That is the sort of spot where a roofer opens up the shingles around the unit and rebuilds them, not just reseals.
Where a house sits in a local historic district, such as Newton Upper Falls, parts of Weston, Lexington or Brookline, adding a skylight changes the way a roof looks from the street. Ask the local commission before you choose a position or a type.
Not sure if you're covered? Check your ZIP code.
Repairing the metal that seals wall-to-roof joints, dormers, valleys and pipe penetrations on older Newton-area houses.
Leak tracing and repair for Newton roofs, from chimney and valley leaks to meltwater that backs up at the eaves.
Full tear-offs and re-roofs for Newton houses, with the building permit and the ice barrier handled as part of the scope.
Ice removal, leak repair and the attic fixes that stop ridges of ice forming at Newton eaves.
It is unusual. The glass is a sealed unit, and water tends to get in at the frame, the curb or the flashing. If moisture sits between the two panes, the factory seal has failed. That unit usually needs replacement, not caulk. A cracked pane is a different problem and needs replacing.
It can. Water that runs down the light shaft soaks drywall and insulation, and if the leak is long-running it can reach framing. That is why a roofer should look at the shaft and the sheathing as well as the glass. Stop the leak first and dry the shaft before repair.
The published guidance this site uses says a full roof replacement needs a Newton building permit and does not say how a new roof opening is treated. Because a skylight can involve cutting a rafter, ask the Building Department before the work and have the roofer confirm in the quote.
It has a much smaller opening and a simpler dome, but it still has a flashing collar and still depends on its seal. A tube that passes through an insulated attic can also collect condensation. Ask the roofer what the failure points are on the model proposed for your roof.
Usually the old flashing was kept, or the new shingles were not woven into the skylight kit correctly. If the leak began after a re-roof, tell the roofer who did it and call another roofer to look at the unit if needed. Photographs of the area before and after help.
Yes, usually as a curb-mounted unit on a built-up curb flashed into the membrane. The roofer who handles the membrane should do the flashing so the two roofing details are built to work together. See the flat roof and EPDM page for how those roofs are built.