If your sun tunnel is leaking around the roof, the flashing is usually the cause. Flashing creates the weatherproof seal between the sun tunnel dome and your roof covering. When it fails, rainwater can enter your home, causing damp, mould and ceiling damage. Fortunately, flashing repairs are quick, affordable and highly effective.
Why Sun Tunnel Flashing Fails
Flashing problems develop for several reasons, especially in variable UK weather. The most common issues include:
- Cracked or brittle sealant
- Poor original installation
- Lifted tiles or slates around the tunnel
- Wind and storm damage
- UV ageing of rubber gaskets
- Roof movement and settlement
When problems appear at the flashing, leaks usually follow shortly after, therefore early repair is important.
Signs You Need Flashing Repair
Look for the following warning signs:
- Damp patches around the sun tunnel
- Water marks on ceilings
- Drips during heavy rain
- Lifted or loose roof tiles around the dome
- Visible cracks in the flashing material
- Light shining through gaps in the loft
If you notice these symptoms, acting quickly will prevent expensive roof damage.
Flashing Repair vs Replacement
Sometimes a repair works well, but in other situations replacing the flashing kit ensures a long-term fix. The table below shows common scenarios.
| Situation | Best Option | Price Range |
|---|---|---|
| Sealant cracked or missing | Repair | £150 – £300 |
| Minor tile or slate movement | Repair | £150 – £350 |
| Flashing kit damaged or perished | Replacement | £350 – £650 |
| Recurring flashing leaks | Replacement | £450 – £900 |
Flat Roof vs Pitched Roof Flashing Repairs
Flat and pitched roofs use different flashing systems, therefore pricing and difficulty vary.
| Roof Type | Typical Flashing Used | Difficulty | Cost Range |
|---|---|---|---|
| Flat roof | EPDM or felt flashing kits | Medium | £300 – £900 |
| Pitched | Tile or slate flashing kits | Easy | £150 – £450 |
Flashing Repair by Brand
Each manufacturer designs flashing specifically for their sun tunnel systems. Below is a quick reference guide.
Velux Flashing Repair
Velux systems often use rigid tile or slate flashing kits. Repairs usually involve resealing or replacing the kit to prevent leaks.
Solatube Flashing Repair
Solatube flashing uses premium seals designed for long tunnels. Repairs focus on sealing roof membranes or upgrading to a new flashing kit.
Fakro Flashing Repair
Fakro repairs frequently involve adjusting tile alignment and resealing the flashing frame.
LiteLite Flashing Repair
LiteLite replacement kits are affordable. Upgrading old LiteLite flashing significantly improves weather protection.
What Happens During Sun Tunnel Flashing Repair
A typical repair includes:
- Roof inspection to identify flashing damage
- Removal of lifted or damaged tiles/slates
- Cleaning and resealing the flashing joint
- Replacing sealant, gaskets or fixings
- Testing with water to confirm the repair
In most cases, flashing repairs take less than two hours.
Typical Flashing Repair Costs
Price depends on roof type and flashing quality, however the following guide helps with budgeting:
- Minor sealant repair: £150 – £300
- Tile or slate adjustment: £150 – £350
- Complete flashing kit replacement: £350 – £650
- Flat roof membrane repair: £300 – £900
Requesting multiple quotes will give you the best idea of local pricing.
Preventing Flashing Problems
You can reduce flashing issues in the future by:
- Scheduling regular roof inspections
- Ensuring tiles stay secured around the dome
- Using matching brand flashing kits
- Adding additional membrane protection on flat roofs
Good flashing keeps your home dry and your sun tunnel working properly.
Get Free Sun Tunnel Flashing Repair Quotes
Describe your flashing problem and receive up to four free quotes from experienced local specialists. Every installer in our network has valid insurance and experience with sun tunnel leak diagnosis and flashing repair.
Fast, affordable flashing repairs — protect your roof before the next storm.
Frequently Asked Questions
Can flashing be repaired without replacing the whole sun tunnel?
Yes. Most flashing repairs involve resealing or replacing the flashing kit without touching the tunnel itself.
How do I know if flashing is the cause of a leak?
A specialist will check water trails, roof tile movement and gaps around the dome. In many cases, the leak starts at the flashing, not the dome.
Can flashing repairs fix condensation?
Sometimes. Good insulation and flashing together reduce condensation side-effects and moisture problems.
Are flat roof flashing repairs more expensive?
Often yes, because flat roof systems need specific membrane sealing.
How long does flashing repair take?
Most flashing repairs take under two hours.