Skylight Leak Repair

Skylight leaking? You're not alone—skylights are one of the most common leak sources we see. The good news: most skylight leaks are fixable without replacing the entire unit.

Common Causes of Skylight Leaks

Flashing Failure

The most common cause (70%+ of cases):

• Flashing seals the skylight to the roof
• Expansion/contraction loosens connections
• Improper original installation
• Age-related sealant deterioration

Flashing repair is much cheaper than skylight replacement.

Condensation (Not Actually a Leak)

Sometimes what looks like a leak is moisture:

• Warm moist air contacts cold skylight glass
• Water forms and drips down
• More common with single-pane skylights
• Worse in bathrooms and kitchens

Solutions include better ventilation or upgrading to double-pane.

Seal Deterioration

Rubber seals around the glass age:

• UV exposure degrades rubber
• Seals crack and shrink
• Water penetrates around glass edge
• Usually repairable without full replacement

Cracked Glass or Dome

Physical damage to the skylight itself:

• Hail or debris impact
• Stress cracks from temperature swings
• Age-related plastic yellowing and cracking
• May require lens/glass replacement or full unit replacement

Improper Installation

Original installation errors:

• Wrong flashing type for roof material
• Inadequate sealant application
• Poor integration with roofing
• Deck curb issues

Diagnosing Your Leak

Before calling for repair, note:

• Where water appears: Edge, center, frame?
• When it happens: During rain? After rain? On humid days?
• Weather conditions: Wind-driven rain? Heavy storms only?

This information helps identify the cause.

Repair Options

Flashing Repair/Replacement

Most common fix:

• Remove roofing around skylight
• Install new step and head flashing
• Integrate with roofing properly
• Cost: $300-$800 typically

Seal Replacement

For deteriorated seals:

• Remove old sealant completely
• Apply new high-quality sealant
• May include gasket replacement
• Cost: $150-$400 typically

Lens/Glass Replacement

When the glazing is damaged:

• Replace dome or glass unit only
• Reuse existing frame and flashing
• Cost: $200-$600 for materials plus labor

Full Skylight Replacement

Sometimes replacement makes sense:

• Multiple failures simultaneously
• Skylight over 20 years old
• Frame corrosion or damage
• Upgrading to better efficiency

See our skylight installation cost guide.

DIY vs. Professional Repair

Some repairs seem simple but require expertise:

• Flashing work requires roofing knowledge
• Improper repair can cause more damage
• Working on roofs is dangerous
• Professional work is warrantied

Contact us for professional skylight leak diagnosis and repair.