Roof Repairs UK helps you compare free, no-obligation quotes from local roofers for skylight leak repairs, including flashing repairs and making good around the roof window.
Describe where the leak is showing + add your postcode to get free quotes.
Common Signs of a Skylight Leak
Look out for:
- Drips from the top corners or along the window frame
- Damp patches or bubbling paint around the reveal
- Water staining on the ceiling below the skylight
- Damp insulation in the loft near the roof window
- Leaks that worsen in wind-driven rain
- Condensation that seems excessive around the window
Tip: Condensation can mimic a leak. However, staining after rainfall usually points to water ingress from outside.
Why Skylights Leak (Most Common Causes)
| Cause | What happens | Typical fix |
|---|---|---|
| Failed flashing around the skylight | Water tracks behind the flashing kit | Repair/replace flashing, re-seat tiles |
| Blocked drainage above the skylight | Water backs up and finds a path inside | Clear debris, check underlay and drainage |
| Slipped/broken tiles or slates nearby | Water enters beside the frame | Replace/re-fix tiles, check underlay edge |
| Incorrect installation detail | Poor overlaps or missing elements | Correct detailing, refit kit properly |
| Underlay issues | Water tracks along underlay into opening | Repair underlay around opening |
| Sealant-only “repairs” | Temporary fix fails in weather | Proper flashing-based repair |
Skylight Leak Repair Cost Guide (UK)
Costs depend on roof type (tile/slate), height/access, and whether a flashing kit needs replacing.
| Repair type | Typical cost range | Notes |
|---|---|---|
| Minor re-seal / local check (limited scope) | £150–£350 | Only suitable when detailing is sound |
| Re-seat tiles and repair flashing (localised) | £250–£900 | Common fix for leaks around frame |
| Replace skylight flashing kit (tile/slate roof) | £350–£1,200 | Depends on access and roof pitch |
| Repair surrounding tiles/underlay (localised) | £250–£1,000 | If water tracks under coverings |
| Internal making good (patch plaster/paint) | £120–£600 | Often after the roof leak is fixed |
| Scaffolding (if required) | £450–£1,800+ | Often needed for safe access |
Tip: A proper quote should separate roof work from internal making good. That way, you can prioritise the watertight fix first. There are some that offer a specific Velux repairs service or roofers that also specialise in sun tunnels repairs.
What Roofers Check Around a Skylight
A good roofer won’t just “seal the edges”. Instead, they’ll check:
- the flashing kit (top, sides, bottom apron)
- tile/slate alignment and cuts around the window
- the condition of battens and underlay at the opening
- drainage above the skylight (valleys, moss, debris)
- any signs of movement or gaps at the junctions
Quick Troubleshooting: Leak or Condensation?
Skylights can create condensation issues in bathrooms and loft rooms. Here’s a quick guide:
| Symptom | More likely | What to do |
|---|---|---|
| Water appears after showers, not rain | Condensation | Improve ventilation, use extractor, check trickle vents |
| Droplets on the glass itself | Condensation | Wipe and monitor, improve airflow |
| Staining appears after rainfall | Leak | Arrange a roofer inspection |
| Damp patches at the top corners | Leak/flashing | Get flashing and tiles checked |
| Water tracks down the plasterboard | Leak from above | Check drainage and flashing above |
How to Get Quotes for a Skylight Leak Repair
Step 1: Describe the leak pattern
For example: “leaks only in wind-driven rain”, “drips from top corner”, or “stain after heavy rain”.
Step 2: Add your postcode
Local roofers can respond with availability and quotes.
Step 3: Compare quotes and choose
Compare scope, access, and whether they will repair/replace the flashing kit properly.
Get Free Skylight Leak Repair Quotes
FAQs – Leaks Around Skylights
Is a skylight leak usually caused by the window itself?
Often no. The skylight unit may be fine, but the flashing kit or surrounding tiles/slates may be letting water in.
Can you fix a skylight leak with sealant?
Sealant might slow a leak temporarily. However, the long-term fix usually involves repairing or replacing flashing and re-seating surrounding tiles.
Do you need to replace the skylight to fix the leak?
Not always. If the skylight is in good condition, roofers often repair the flashing and surrounding roof covering instead.
Why does it only leak in heavy rain or wind?
Wind-driven rain can force water into small gaps at flashing overlaps and tile joints. That’s why leaks can appear only in storms.
Should I fix internal damage before the roof repair?
No. Fix the roof leak first. Otherwise, damp patches and staining can return.