Skylight Leaking in Miami? Why It Happens & the Re-Roofing Rule That Saves You Money

The short answer: A leaking skylight in South Florida is usually a flashing or seal failure, not a cracked dome — and the single biggest skylight mistake Miami homeowners make is re-roofing around an old skylight instead of replacing it while the roof is open. Canopy Roofing repairs and replaces skylights across Miami-Dade and Broward as part of roof repair and re-roofing work; skylight-related repairs start at $1,500, and replacing a skylight during a re-roof costs a fraction of doing it as its own project later.

Here’s our own quick explainer on skylights from the Canopy Roofing Report series:

Why Skylights Leak in South Florida

A skylight is a hole in your roof with a window in it. That’s not a criticism — done right, it’s a beautiful, durable assembly. But it means a skylight has to survive everything the roof survives, plus manage its own perimeter. In Miami that perimeter faces near-daily summer rain, UV that destroys sealants in a few years, salt air, and hurricane-season uplift. The failure points, in the order we actually find them:

• Flashing. The metal assembly where the skylight curb meets the roof covering. This is where most “skylight leaks” actually live — the skylight itself is fine, the transition is not. (The same cap-vs-flashing confusion we covered for chimneys applies here.)
• Perimeter seals. UV-baked sealant around the frame cracks and shrinks. Caulk smeared over old caulk is the signature of a handyman visit, and it buys months, not years.
• The curb. On older installs, the wooden curb itself rots once water finds it, and no amount of surface sealing fixes rotted wood.
• Condensation, not a leak at all. In our humidity, a single-pane or failed-seal skylight can drip from condensation alone. If the “leak” shows up on dry sunny days after cool nights, suspect condensation.
• The dome or glass. Genuinely cracked acrylic domes happen — usually from debris strikes or someone stepping where they shouldn’t — but it’s the least common cause on our repair calls.

Water from a skylight rarely drips straight down from it. It tracks along the framing and shows up as a ceiling stain several feet away — one more reason to read our guide to roof leak warning signs before assuming where a leak starts.

The Re-Roofing Rule: Never Roof Around an Old Skylight

This is the part of the video worth repeating, because it saves homeowners real money. When you replace your roof, every skylight on it should be replaced at the same time — even the ones that aren’t leaking yet. Here’s why:

The economics only work once. During a re-roof, the covering around the skylight is already off, the crew is already up there, and new flashing is already being fabricated. Replacing the unit at that moment adds a modest line item. Replacing it three years later means opening up a brand-new roof — its own crew, its own setup, its own flashing work, and a patch in a covering that no longer has a factory-uniform age.

The warranty math is worse. A 20-year-old skylight on a brand-new 25-year roof is the first thing that will fail, and when it does, the repair disturbs the new covering. Some manufacturers’ roof warranties get complicated when the leak source is a pre-existing skylight the roofer was told to leave in place.

Code has moved. Skylights in Miami-Dade and Broward sit in the High-Velocity Hurricane Zone and need current Notice of Acceptance (NOA) rated units — impact-rated glazing matters when the airborne debris starts flying. Pre-2002 units generally don’t meet today’s standard. A re-roof is the natural moment to bring them current.

Repair or Replace? How We Call It

Repair — starts at $1,500. Failed flashing on a sound unit, perimeter re-seal with the covering opened properly (not surface caulk), or localized covering repair around the curb. What moves the price: roof covering type (tile means more tile up and down — see Miami roof repair), pitch and access, and whether the curb framing is dry.

Replace the unit. Rotted curb, failed insulated glass (permanent fogging between panes), a discontinued dome profile, or any pre-NOA unit on a roof that has life left. Modern units are impact-rated, far better insulated — a real difference on a Miami AC bill — and available with fresh factory flashing kits.

Replace it with the roof. If your roof is within a few years of end of life, don’t spend repair money twice. The honest conversation is roof replacement with new skylights as part of the scope, and financing turns the whole package into a monthly number. Hablamos español — visita cambio de techo en Miami.

Where Canopy Roofing Works

Miami
Coral Gables
Pinecrest
Key Biscayne
Coconut Grove
Miami Beach
Miami Shores
Fort Lauderdale
Hollywood
Weston
Coral Springs
Plantation

Frequently Asked Questions

Why is my skylight leaking when it rains?

Most often the flashing where the skylight curb meets the roof covering has failed, or the perimeter sealant has UV-cracked — not the skylight glass or dome itself. In South Florida, condensation on single-pane or failed-seal units also mimics a leak. A roof-level inspection tells you which one you have.

How much does skylight leak repair cost in Miami?

Canopy Roofing repairs involving a skylight start at $1,500. The price moves with the roof covering (tile costs more to open and close than shingle), pitch and access, and whether the curb framing underneath is still dry. Full unit replacement is priced after inspection.

Should I replace my skylights when I replace my roof?

Yes, almost always. During a re-roof the covering is already open and new flashing is already being made, so the skylight adds a modest line item. Replacing it later means opening up a new roof. An old skylight is also the most likely first failure point on a new roof.

Do skylights in Miami need to be impact rated?

Miami-Dade and Broward are in Florida’s High-Velocity Hurricane Zone, and skylights installed here need units with a current Notice of Acceptance (NOA). Modern impact-rated glazing is designed for wind-borne debris; most pre-2002 units don’t meet today’s standard.

Can I just caulk a leaking skylight?

Surface caulk over old sealant buys months at best, and it often makes the eventual proper repair harder by hiding where the water enters. A lasting fix means opening the covering at the curb and redoing the flashing and seals as an assembly.

The Bottom Line

Skylights are the best and worst thing on a South Florida roof: natural light all year, and a perimeter that has to be detailed perfectly to survive our weather. When one leaks, it’s almost always the flashing or seals, and the fix is roofing work, not caulk. And whenever a roof replacement is on the table, the skylights go with it — that’s the one moment replacing them is cheap. Canopy Roofing handles skylights as part of repair and re-roofing across Miami-Dade and Broward. More South Florida roofing guides on the Canopy Roofing blog.