A wet skylight is often not a leaking skylight. Separating a genuine seal failure from condensation and from a curb flashing problem decides what actually needs doing.
The useful first question is when the water appears rather than where. Condensation peaks on cold, still, dry nights; a curb flashing fault tracks rain and wind direction; a failed glazing unit ignores both and simply gets worse. Establishing which pattern fits takes a few days of observation and costs nothing.
Two of the three causes need no roof work at all. Ruling them out first is what prevents an unnecessary repair to a skylight that was never leaking.
A wet skylight is one of the few roof complaints where the most likely answer needs no roof work at all. Ruling the other two out first is what stops an unnecessary repair.
A skylight is the coldest surface in a warm, humid room. Water forming on the inside of the glass and running down the reveal appears in cold weather, is worst in kitchens and bathrooms, and stops when the room is ventilated. No roof work will change it.
The unit itself has failed — misting between panes, water at the glazing bar. This is a window fault rather than a roof fault, and it is solved by the unit, not by the roof around it.
The skylight sits on a raised curb, and that curb is flashed into the roof like a small chimney: apron at the bottom, steps up the sides, head flashing at the top. Water entering here appears at the corners of the reveal and is worst in driven rain from one particular direction.
Condensation is worst on cold still nights with no rain at all. A curb flashing leak tracks rainfall and wind direction. A failed unit leaks regardless of both. Establishing which pattern fits takes observation, not a ladder.
Exposed roofs drive rain at skylight curbs from the side rather than from above. A curb that sheds vertical rain perfectly well can still let water past its head flashing in a strong wind.
Reference point: the Meadowlands edge of the Passaic river towns.
The commercial and light-industrial buildings here carry big low-slope roofs where the failure mode is ponding and seam separation, not the shingle and flashing problems that dominate the dense residential boroughs upriver.
Exposure matters more here than in the sheltered street walls of Passaic: open sites take wind uplift at the roof edge that a hemmed-in city block never sees.
Low density by the standards of this area -- under three thousand per square mile -- with a mix of older borough housing and a large share of land given over to commercial and stadium-district use.
All areas coveredUseful to know before accepting any quote, because a scope that ignores these is a scope that will have to change later.
New Jersey adopts a single Uniform Construction Code and municipalities may not set lesser or greater technical requirements. A repair specified correctly in Passaic is specified correctly in Clifton.
Replacing more than a quarter of a roof surface within any twelve-month period triggers a full construction permit. Splitting one job into two smaller ones inside that window does not avoid it.
Northern New Jersey sits in the design zone where an ice barrier is required, running from the eave edge to at least twenty-four inches inside the interior wall line. On older roofs it is frequently absent, which shows up as recurring winter leaks at the eaves.
In Passaic the Uniform Construction Code is enforced by the city's Division of Code Enforcement, which is where permits for qualifying roof work are issued.
The same job in the areas next door, and the other leak types we handle in this one.
Answers are general guidance about how these roofs behave, not a survey of any particular building.
Probably not. Condensation forms on the coldest surface in a warm humid room, which a skylight usually is. It is worst on cold still nights and improves with ventilation. A genuine leak tracks rainfall and wind direction instead.
Roofs here are larger and more exposed, so the edges matter more than the middle. After any wind event the eaves, rakes and ridge are worth checking even if nothing has shown inside yet.
Only if more than a quarter of the roof surface is replaced within a twelve-month period — that is the threshold under the New Jersey Uniform Construction Code. Most targeted leak repairs sit well under it, but the scope decides, not the label on the job.
Describe what you are seeing and when it started — that is usually enough to narrow the cause before anyone climbs anything.