Almost every leaking skylight fails in one of four places. That is the useful thing to know before you call anyone, because the four have very different causes, very different fixes and very different prices. Requests for skylight repair Newmarket homeowners make in September and October follow the same pattern year after year: the first long, steady rain of the season finds the weak detail, a stain appears on the ceiling, and the problem gets a name only once somebody lifts the shingles.
This guide works through each of the four leak points in turn, explains what the repair involves and what it costs in 2026, covers the fifth complaint that is not a leak at all, and sets out the point at which repairing stops being the sensible choice.
Why Skylight Repair Newmarket Enquiries Arrive In Waves
Summer rain is short and sharp. A marginal flashing detail often survives a twenty minute thunderstorm because the volume passes before water can back up anywhere. Autumn rain is long, steady and frequently driven sideways by wind, and that is a completely different test. Six hours of it will find any joint that depends on sealant rather than on layered metal, which is why skylight repair Newmarket calls cluster in the weeks after the weather turns.
Leaf fall compounds it. Newmarket has mature trees through its older neighbourhoods, and leaves blown against the upslope side of a skylight hold water exactly where it should be running away. On a low pitched roof this can be enough on its own to push water past a head flashing that would otherwise cope.
Timing the repair matters as much as diagnosing it. Booking skylight repair Newmarket work in early autumn means the shingles are still warm and pliable enough to be lifted and reseated without cracking, and flashing cements still reach a full cure at daytime temperatures in the low teens and above. A repair done now is a permanent repair. The same work attempted in a narrow window between storms rarely is.
Leak Point One: The Head Flashing And The Missing Saddle
Of all the skylight repair Newmarket jobs we attend, this is the most common failure by a wide margin. Water running down the roof above the skylight has to be diverted around the unit, and the head flashing is what does it. The piece must be lapped under the shingle course above so that water passes over the metal and back onto the roof. Where an installer instead laid the head piece on top of the shingles and ran a bead of roof cement across it, the detail works for a few seasons and then stops.
The second version of this problem appears on roofs with a long run above the unit. The volume of water arriving at the head is simply too great for a flat piece of metal to divide cleanly, and a saddle, sometimes called a cricket, is needed to split the flow and send it around each side. Many older installations never had one.
The repair is to strip back the shingle courses above the unit, remove the old head assembly, fit the correct manufacturer piece with the proper laps, and where required build a saddle. It is genuine roofing work rather than a patch, and it lasts.
Leak Point Two: Step Flashing That Was Never Woven In
The second point on any skylight repair Newmarket diagnosis is the side of the unit, where water has to be handed down the roof from course to course. That is what step flashing does: one piece per shingle course, each lapping the piece below it and tucking under the shingle beside it. Done properly it is invisible and effectively permanent.
The failure mode is an installation that used a single continuous L shaped strip along the side, face nailed and sealed. Every fastener through that strip is a hole in the water path, and the sealant over them has a service life measured in a handful of years. Once it shrinks and cracks, water tracks in along the nails. On a skylight repair Newmarket inspection this is usually visible as soon as the first shingle is lifted.
Correcting it means removing the strip, fitting proper step pieces course by course, and reseating the shingles. It takes longer than the head repair because more of the roof has to be opened, and it is the fix most often quoted as though it were a simple recaulk. It is not.
Leak Point Three: The Perimeter Gasket And Frame Corners
The third skylight repair Newmarket leak point is on the unit rather than the roof. Between the glazing and the frame there is a gasket, and around the frame corners there are factory joints. Both harden with age and ultraviolet exposure. On units past twenty years old the gasket can shrink away from a corner enough to admit water even though every piece of flashing on the roof is correct.
Where the manufacturer still supplies a replacement gasket for the model, fitting one is a worthwhile repair. Where the model has been discontinued and no gasket is available, there is no honest repair, and any contractor offering to solve it with sealant is selling you a season. This is one of the clearest cases where the right answer is replacement rather than continued skylight repair Newmarket spending.
Check the glazing at the same time. If there is haze or moisture trapped between the panes, the insulated glass seal has failed and the unit is finished regardless of gasket condition, because on residential skylights the glass and frame are supplied as one sealed factory assembly.
Leak Point Four: The Roof Deck Around The Opening
The fourth skylight repair Newmarket leak point is the one homeowners never see and contractors sometimes ignore. Once water has been getting in for a season or two, the plywood or board sheathing around the opening softens. Soft sheathing will not hold a fastener properly, and a new flashing kit fixed into it will loosen within a year or two, which is how a skylight comes to be repaired three times.
Deck condition is checked by pressing the sheathing all round once the unit is out, and by looking for dark staining and delamination. Anything compromised is cut back to sound material and replaced. It adds a few hundred dollars and it is the difference between a repair that holds and one that does not.
This is also the point at which the framing gets a look. A slightly sagging header or a previous repair that added blocking in an unhelpful place will show up here. Minor corrections are made in place; anything genuinely structural stops the work until it is properly designed.
Skylight Repair Newmarket Costs By Leak Point
The ranges below reflect typical 2026 residential pricing in the Greater Toronto Area for work on a pitched asphalt shingle roof, and they assume the unit itself is sound.
| Leak point | Repair | Typical 2026 cost |
|---|---|---|
| Head flashing | Replace head piece with correct laps | $450 to $950 |
| Head flashing, long run above | Build a saddle or cricket | $650 to $1,400 |
| Step or side flashing | Remove strip, fit step pieces per course | $700 to $1,600 |
| Perimeter gasket | Replace where the manufacturer supplies one | $350 to $800 |
| Roof deck around the opening | Cut out and replace soft sheathing | $300 to $900 |
| Diagnostic inspection with staged water test | Isolate the entry point | $150 to $350 |
Interior work is separate. Drywall patching, taping and painting in the shaft typically runs $350 to $1,100 depending on depth and how much staining there is. Treat any quote for skylight repair Newmarket work that ignores the interior entirely with mild suspicion, because if water reached the ceiling, something inside needs attention.
The Fifth Complaint, Which Is Not A Leak
A large share of the calls that come in through October describe a leak that is not one. It is condensation, and it behaves differently in ways you can observe yourself before anyone climbs a ladder.
Condensation appears on cool mornings, often with no rain at all, and dampens the shaft evenly down all four sides. A genuine leak appears during or just after rain, and concentrates at one corner or along the head. Condensation gets worse after showers, cooking and drying laundry indoors. A leak gets worse with wind from one particular direction.
The cause is warm, humid indoor air reaching a cold surface, and the cure is not on the roof. It is continuous insulation against the shaft walls, a properly air sealed joint between the shaft framing and the ceiling drywall, and an exhaust fan that actually discharges outdoors rather than into the attic. A fan dumping moist air under the roof deck will fog and wet a skylight no matter how well the flashing was done, and we check for it on every skylight repair Newmarket inspection.
How To Describe The Problem When You Call
A clear description gets you a better skylight repair Newmarket diagnosis and often a cheaper visit. The table below translates what you can observe into what it usually means.
| What you observe | Most likely cause | Typical fix |
|---|---|---|
| Water at the top corners during heavy rain | Head flashing or missing saddle | Rebuild the head detail |
| Water down one side only, wind driven | Step flashing fitted as a sealed strip | Fit proper step pieces |
| Slow drips with no obvious pattern | Perimeter gasket or frame corner | Replace gasket, or replace the unit |
| Staining that returns after a previous repair | Soft roof deck around the opening | Replace sheathing and re-flash |
| Even dampness on all four shaft sides, cool mornings | Condensation | Air seal and insulate the shaft |
| Permanent haze between the panes | Failed insulated glass seal | Replace the unit |
Photographs help enormously. A picture of the stain pattern on the shaft, taken in daylight, tells an experienced estimator more than a five minute phone description.
Newmarket Homes And The Skylights In Them
The town’s housing spans a broad range of ages, and the pattern of skylight repair Newmarket requests follows it closely. Older brick homes in the central neighbourhoods often have skylights added later during a renovation, and retrofit installations are more variable in quality than factory specified ones, so flashing faults are common on these.
Subdivisions built through the 1980s carry a good number of original acrylic dome units on site built timber curbs. Acrylic goes yellow and brittle with ultraviolet exposure, and those curbs were rarely flashed to modern standards, so these are more often replacement candidates than repair candidates. Homes from the 1990s and 2000s in the newer communities at the edges of town typically have glass units on steeply pitched roofs, now reaching the age at which the insulated glass seal governs. Where the glazing is still clear on those, a targeted flashing repair is usually excellent value.
Because the stock is so varied, a phone quote is guesswork. You can read more about how we work locally on our skylight installation and repair in Newmarket page, and our skylight repairs service page sets out what a standard diagnostic visit covers.
Where Repair Stops Making Sense
There is a point at which further skylight repair Newmarket spending is poor value, and it is worth being clear about it before you commit.
| Condition | Recommendation | Why |
|---|---|---|
| Glazing clear, frame sound, flashing wrong | Repair | Years of service remain in the unit |
| Moisture sealed between the panes | Replace | The seal cannot be restored |
| Gasket unavailable for a discontinued model | Replace | No durable repair exists |
| Yellowed or crazed acrylic dome | Replace | The plastic is degraded throughout |
| Third repair on the same unit | Replace | Frame or deck is likely compromised |
| Repair cost above half a replacement | Replace | Resets both warranties |
For reference, a single unit replacement on a shingle roof typically runs from $1,600 to $4,800 installed depending on whether it is fixed, venting or solar powered. Once a proposed repair approaches half of that, replacement is usually the better decision, because you get a new product warranty and a new workmanship warranty rather than another few seasons on an old assembly.
What A Proper Repair Visit Includes, And What Prevents The Next One
A serious skylight repair Newmarket appointment starts inside, not on the roof. The technician looks at the stain pattern, checks the shaft for air leakage and looks for internal moisture in the glazing, then checks the attic where accessible for wet insulation, stained sheathing and any exhaust duct discharging into the roof space. Only then does the roof inspection happen, with shingle courses lifted at the head to see how the flashing was assembled and the deck pressed for softness.
A staged water test comes next, applied from the bottom of the unit upward so the entry point is isolated rather than guessed. The repair itself rebuilds flashing in layers from the bottom up, with sealant used only as a secondary defence. The detail is re-tested afterwards, and you should receive photographs of what was found and what was done. Most repairs finish within a single visit of three to six hours.
Prevention is short and cheap. Have leaf litter cleared from above the skylight each autumn, keep gutters and downpipes flowing, run the bathroom fan for twenty minutes after a shower rather than five, and confirm that the fan vents outdoors. Book an inspection rather than waiting for a stain. Toronto Skylight Installers inspects across the Greater Toronto Area and will tell you plainly when nothing needs doing.
Where do skylights leak most often?
What does skylight repair Newmarket service cost?
My skylight only drips on cold mornings. Is that a leak?
Can sealant fix a leaking skylight?
How quickly should I book skylight repair Newmarket work?
When is replacing better value than repairing?
Book Skylight Repair Newmarket Homeowners Can Trust
If a stain has appeared on the ceiling, a corner is damp after rain or the glass has gone permanently hazy, a proper diagnostic visit identifies which of the four leak points is responsible before any work is quoted. Toronto Skylight Installers handles skylight repair Newmarket projects with an interior assessment, an attic check, a roof inspection and a staged water test, and provides photographs of what was found and what was done.
Call us today at (416) 365-7557 or request a free consultation before the wettest part of the season arrives.
Proudly serving Newmarket and communities across the Greater Toronto Area.