Skylight, Curb and Penetration Flashing in Rockford, IL
Skylight, curb, pipe boot and pitch pocket flashing repair in Rockford, IL, built for drifting snow, ice and the leaks that start at roof openings.
Skylight, Curb and Penetration Flashing
Skylight, Curb and Penetration Flashing
Rockford, IL
Snow drifts against every skylight and curb on a Rockford, IL roof, and a drift does not melt evenly. The side facing the sun thaws and sends water down the curb, the shaded side stays frozen, and by evening the whole thing refreezes against the flashing. With winter snowfall piling up and freezing weather on about 134 days a year, the seal at a roof opening gets pulled, wetted and frozen again over and over before it ever sees a summer. That is why many commercial leaks start at penetrations and not in the open field of the membrane. A pipe boot, a hatch, a skylight dome, an exhaust curb and a conduit all break the roof, and every one of them has a flashing detail that has to survive that cycle.
If a roof is leaking and the field looks fine, start at the openings.
Check where the snow piles up and the water follows
Water finds the lowest and most protected spot, and openings are full of both. Snow collects on the uphill side of a curb and holds meltwater against the flashing for days. A pipe boot cracks from sun in July and ice in January, and the crack lets water run straight down the pipe. A skylight frame that sat tight in August opens a hairline gap in a cold snap, and the next thaw drives water through it. We look at every opening on a roof: boots, stacks, hatches, conduits, equipment curbs, smoke vents and domes. We check the base flashing, the counterflashing, the sealants, the fasteners and the condition of the membrane around each, because water often enters at the corner of a flashing where two pieces meet. Our commercial roof leak repair work follows the same logic when the damage is already inside.
Do not trust a dab of sealant at a corner. Sealant is a bandage, not a flashing.
Find the failure at the curb, the dome or the boot
Each opening fails in its own way. A pipe boot goes brittle and splits at the collar. A pitch pocket, which is a metal pan filled with sealant around a penetration, shrinks away from the pipe over a winter or two and leaves a gap that no refill fixes for long. A curb flashing pulls loose at the corners when the substrate underneath moves. Counterflashing opens where it was never lapped properly. A skylight loses its gasket or glazing seal. A plastic dome yellows, crazes and cracks. Each of these has a proper fix, and the proper fix is rarely more sealant. A failed detail usually traces back to the causes behind any flashing failure repair, and the heavier units that sit on equipment curbs and supports add their own load to the same joints.
- Boots: replace with a new boot or a welded or flashed collar
- Pitch pockets: convert to a prefabricated boot or a flashed enclosure
- Curbs: reflash with new base and counterflashing, and raise the curb if drifts reach it
- Domes and glazing: replace when crazed, and add a guard while the opening is exposed
Decide whether to re-flash, raise the curb or replace the unit
The fix depends on the age of the unit and the roof around it. If the skylight or curb is sound and only the flashing has failed, we re-flash. If the curb is too low to stay above snow drifts and ponding water, we raise it and flash the new height. If the skylight is old, with a fogged or crazed dome, a leaking frame or a deteriorating gasket, replacing the whole unit usually costs less than repairing it a third time. A replacement skylight also counts as glazing under the energy code the City of Rockford applies, so ask the building department what the permit will require before you order. Safety matters too. A dome that cannot hold a person's weight is a fall-through hazard for every maintenance worker who steps near it, so a guard or screen is worth adding any time the opening is exposed.
Do not replace a skylight just because it is old. Test it, and replace it when testing says to.
Question the quote that treats every opening alike
A fair proposal counts the openings, names each type and prices each repair. A bad one says re-flash all penetrations for a single number. Ask how many boots, curbs, hatches and skylights are on the roof, which ones are being replaced and which are being repaired, and what material goes on each. Ask whether the membrane around the opening is being cut back to sound material or just patched. Ask whether a roof with a lot of openings has any wet insulation around them, because water at a curb usually runs under the membrane and soaks the board beside it. A hospital roof is the kind of place that can hold a crowd of exhaust penetrations. In the Rockton Avenue corridor, where Mercyhealth's $505 million Javon Bea Hospital-Riverside opened in 2019, hospital roofing work has to be coordinated with facilities staff.
Get the count in writing. A proposal that cannot count the openings has not been up on the roof.
Separate a leak from condensation before you pay for either
A skylight that drips in January on a dry day is often sweating, not leaking. Cold glass and metal frames pull moisture out of warm, humid interior air, and the water runs down the curb and into the ceiling tile below. That calls for a thermal break, insulation inside the curb or better building ventilation, not new flashing. We tell the two apart with a hose test, a thermal camera and a close look at when the water appears. If it shows up in the middle of winter with no rain, suspect the air. If it shows up with rain or thaw, suspect the flashing. Insulation inside and around curbs is part of the wider roof insulation and cover board assembly.
Paying for a flashing repair on a condensation problem is money gone and a leak still there.
Fix the openings before the first freeze
Openings are the best small projects to finish in fall. Sealants, adhesives and welds cure better above freezing, and a repaired opening goes into winter holding. Schedule the work for dry days and plan the interior side too, because work above a skylight or in an atrium needs protection below. A campus the size of Rock Valley College's 217 acres on the North Mulford corridor is the kind of portfolio where a single list of roof openings, reviewed every fall, is cheaper than responding to calls one at a time. If the building is open while the work happens, the crew plans around tenants the way it does on any occupied building reroofing job. A maintenance route along Rockford’s south-side 11th Street corridor can benefit from annual skylight and curb inventories.
Questions Owners Ask
Is my skylight leaking or just sweating?
Dripping in cold weather with no rain usually means condensation. Water that appears during or after rain points to a failed seal or flashing. A thermal camera and a hose test separate the two.
Can a pitch pocket be saved or should it go?
Refilling it helps for a season. Replacing it with a prefabricated boot or a flashed collar lasts, because sealant in a pan shrinks and cracks every winter.
What should I do about a yellowed, crazed skylight dome?
Replace it. Crazing means the plastic is losing strength, and a hail strike or a worker's weight can break it. Add a guard while the dome is off.
Can the curb be raised if snow keeps drifting over it?
Yes, in many cases. A taller curb with new flashing keeps drifts and meltwater from reaching the joint. We check the unit and the structure before raising it.
Will new skylights trigger code work?
Often they do, since glazing falls under the energy code and the permit may ask for compliant products. Ask the City of Rockford building department before you order.
How do you protect the space below a skylight during replacement?
We cover and tent the area, set up debris catches, work around your hours and close the opening with a temporary cover each night. Tell us what sits below.
