Leaking Skylight? Here’s When You Can Repair It Instead of Replacing It in London, Ontario
A skylight can brighten up your home, boost curb appeal, and even improve ventilation. But when it starts to leak, fog up, or cause water stains on your ceiling, it’s natural to worry about the cost of replacing it. The good news is, in many cases, you may only need a professional resealing or minor repair — saving you hundreds of dollars.
At B&B Roofing & Exteriors, we’ve been helping homeowners in London and St. Thomas make smart, cost-effective decisions for their homes. Here’s how to know whether your skylight can be repaired or if it’s time for a replacement.
Common Signs of a Skylight Problem
Not all leaks mean your skylight is finished. Watch for these signs:
Water spots around the skylight frame after heavy rain
Condensation or fogging between glass panes
Drafts or cool air leaks
Cracked or peeling sealant
Debris buildup causing water pooling
In many cases, these issues are due to worn sealant, minor flashing problems, or clogged exterior drainage — all of which can be fixed without a complete skylight replacement.
Can a Skylight Be Resealed?
Yes — if the glass is intact and there’s no severe frame damage, most modern skylights can be resealed. A professional will clean away the old, cracked sealant and apply a fresh, weather-resistant barrier. This helps prevent water from sneaking in around the edges.
Resealing is especially useful after a tough Ontario winter, when freeze-thaw cycles can loosen sealants and caulking.
When to reseal a skylight:
No visible cracks in glass
Water appears only during certain weather
Sealant visibly cracked or missing
The frame is still structurally sound
When Should You Replace Your Skylight?
Sometimes, a full replacement is the smarter long-term move. Replacement makes sense when:
Glass is cracked or fogging between panes
Frame is rusted, rotten, or warped
Leaks persist even after resealing attempts
You want a more energy-efficient model
Upgrading to a modern product like Velux skylights can also improve insulation, reduce UV damage inside your home, and add resale value.
👉 Learn more about Velux skylights here: Exterior Window & Door Replacement Services
How Much Does Skylight Resealing Cost in London, ON?
Resealing a standard skylight typically costs between $250 and $500 in the London area, depending on:
The size of the skylight
Roof pitch and accessibility
Amount of old sealant removal required
Number of skylights being serviced
A new skylight installation, on the other hand, can run between $1,200 and $2,500+ including removal, disposal, and installation.
DIY vs. Professional Skylight Repair
While small resealing jobs might look manageable, we don’t recommend it unless you have roofing experience. Working on a roof is dangerous without the right equipment, and improperly applied sealant can make leaks worse.
Professional benefits:
Safe, proper ladder and harness use
Correct sealant and flashing materials
Workmanship warranty
Quick detection of hidden frame issues
Seasonal Skylight Maintenance Tips
To avoid future leaks and costly repairs:
Clean debris from around the skylight every spring and fall
Inspect caulking and sealant twice a year
Check for condensation during cold weather
Call for a reseal or assessment before Ontario’s harsh winter sets in
Call B&B Roofing & Exteriors for a Skylight Assessment
If you’re dealing with a leaking or fogged skylight, give B&B Roofing & Exteriors a call. We’ll inspect your skylight, let you know if a reseal will fix it, and provide fair, honest pricing for repairs or replacements.
Contact us today for a free skylight assessment in London, St. Thomas, and surrounding areas.
