How can I tell if it's a leak or just condensation?

Condensation usually shows up as moisture on the inside of the glass in cold weather and tends to appear and disappear with temperature swings. A true leak is more often tied to rain or snowmelt and leaves staining that keeps spreading.

Can a leaking skylight be repaired without replacing the whole unit?

Often yes. Many leaks come down to worn flashing or sealant around the frame, which can be repaired without removing the skylight itself. A full replacement is usually only needed if the glass unit or frame has failed.

How urgent is a skylight leak?

Treat it like any active roof leak. Water tracking down through the ceiling around a skylight can damage drywall and insulation the longer it's left, so it's worth having it looked at promptly rather than waiting.

Does fixing a skylight leak affect my roof warranty?

It can, if the work disturbs shingles or membrane covered under a roofing warranty. Ask the contractor how the repair interacts with any existing roof warranty before work starts.

Skylight leak repair near you

A skylight is one of the most common spots for a roof to leak, because it's a cut through the roofing material that has to be flashed and sealed correctly to stay watertight. Over time, the rubber gasket or sealant around the frame breaks down, flashing can corrode or pull away, and on older skylights the insulated glass unit itself can fail.

Not every stain around a skylight is a roof leak. Condensation forms on the inside of the glass or frame in cold weather and can drip in a way that looks identical to a water leak from outside. A contractor who does skylight leak repair will check both possibilities before opening anything up, since the fix for condensation (usually ventilation or an interior air leak) is completely different from the fix for a failed flashing seal.

Depending on what they find, the repair might be as simple as re-caulking and replacing step flashing, or it might mean the skylight unit itself needs to come out and be reset or replaced. Because the skylight ties directly into the surrounding shingles or roofing membrane, this work needs to be done by someone who understands both the skylight and the roofing system around it.

What it costs

Cost depends on whether the fix is resealing and flashing repair or a full skylight unit swap, plus the size of the skylight, how steep and high the roof is, and how the surrounding roofing material needs to be reintegrated once the work is done.

Top 3 by our score

Ranked from our published scoring of public Google reviews for skylight contractor.

1. The Roof Technician Toronto - Roof Repairs - Flat Roofing - Skylights
5.0★ · 149 reviews

93
2. Prime Roof Repairs Company Toronto
5.0★ · 210 reviews

95
3. High Skillz Roofing Inc. | North York
5.0★ · 208 reviews

94

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FAQ

How can I tell if it's a leak or just condensation?: Condensation usually shows up as moisture on the inside of the glass in cold weather and tends to appear and disappear with temperature swings. A true leak is more often tied to rain or snowmelt and leaves staining that keeps spreading.
Can a leaking skylight be repaired without replacing the whole unit?: Often yes. Many leaks come down to worn flashing or sealant around the frame, which can be repaired without removing the skylight itself. A full replacement is usually only needed if the glass unit or frame has failed.
How urgent is a skylight leak?: Treat it like any active roof leak. Water tracking down through the ceiling around a skylight can damage drywall and insulation the longer it's left, so it's worth having it looked at promptly rather than waiting.
Does fixing a skylight leak affect my roof warranty?: It can, if the work disturbs shingles or membrane covered under a roofing warranty. Ask the contractor how the repair interacts with any existing roof warranty before work starts.

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