A damaged or discoloured sun tunnel dome can reduce daylight and allow water into your home. Fortunately, replacing the dome is one of the quickest and most affordable sun tunnel repairs. A new dome restores light output, improves energy efficiency, and protects your roof from leaks.
Why Sun Tunnel Domes Need Replacing
Sun tunnel domes sit on your roof and face constant exposure to weather. Over time, sunlight, rain, wind, temperature changes and debris can weaken the material.
Common dome issues include:
- Yellowing or fogging
- Cracks or splits
- Loss of clarity
- Damaged seals
- Broken clips or fixings
When the dome deteriorates, you will often notice a drop in light levels, moisture around the diffuser, or even visible drips during heavy rain.
Benefits of Dome Replacement
Replacing the dome has several advantages compared with replacing the entire system:
- Faster installation
- Lower cost
- Improved clarity and daylight
- Better weather protection
- No major roof work
- No structural changes
In most cases, a dome replacement takes less than an hour.
Dome Material Comparison
Not all sun tunnel domes are the same. Modern systems use advanced polymers that perform far better than older acrylic models.
| Dome Material | Light Clarity | Weather Resistance | UV Protection | Cost |
|---|---|---|---|---|
| Polycarbonate (modern) | Very high | Excellent | Excellent | £££ |
| Acrylic (older style) | Moderate | Fair | Poor | ££ |
| Glass dome | Very high | Very good | Excellent | ££££ |
Polycarbonate domes provide the best balance of durability, clarity and cost.
Brand Dome Replacement Comparison
Different manufacturers offer different dome designs and seal systems. The table below shows common replacement options and typical price ranges.
| Brand | Typical Dome Type | Best Feature | Dome Cost Range |
|---|---|---|---|
| Velux | Polycarbonate | Excellent flashing seal | £80 – £200 |
| Solatube | High-clarity polymer | Maximum light transmission | £120 – £300 |
| Fakro | Polycarbonate | Good value, long warranty | £80 – £160 |
| LiteLite | Acrylic / Poly | Affordable replacement | £60 – £140 |
Tip: Upgrading from an old acrylic dome to a modern polycarbonate dome can increase light output by 20–30%.
Signs You Need a Dome Replacement
- The dome looks cloudy or yellow
- Light levels have dropped noticeably
- You see cracks or splits in the surface
- Water drips or leaks during rain
- Wind lifts or rattles the dome
- The roof seal looks loose or broken
If you notice any of these, you should arrange a dome inspection soon.
Flat Roof vs Pitched Roof Dome Replacement
| Roof Type | Typical Dome Style | Replacement Difficulty | Cost Range |
|---|---|---|---|
| Flat roof | Flat flashing & membrane | Moderate | £150 – £350 |
| Pitched | Tile/slate flashing kits | Easy | £80 – £200 |
Dome Replacement Process
A trained installer usually follows these steps:
- Remove the existing dome safely
- Check flashing and seals for damage
- Install a new dome with fresh fixings
- Replace weather strip or gasket
- Test with water to confirm the seal
You will see improved daylight as soon as the installer finishes.
Typical Dome Replacement Costs
Prices depend on brand and roof type, however the following guide will help you budget:
- Dome unit only: £60 – £300
- Full dome replacement service: £150 – £350
- Flat roof dome replacement: £200 – £450
To get precise pricing, request quotes from local specialists.
Get Free Sun Tunnel Dome Replacement Quotes
Tell us about your current sun tunnel and receive up to four free quotes from local installers. All contractors are vetted, insured and experienced in dome replacement for Velux, Solatube, Fakro and LiteLite systems.
Restore brightness and stop leaks — get your free dome replacement quotes today.
Frequently Asked Questions
Can I replace just the dome without changing the whole sun tunnel?
Yes. Dome replacement is the most common sun tunnel repair, and most systems allow easy dome swapping.
How long does a dome replacement take?
Most dome replacements take under an hour.
Will I need roof access?
Yes. Installers will fix the dome at roof level and confirm a weatherproof seal.
Do domes come in different sizes?
Yes. Different brands use different diameters, so using a matched dome helps ensure a proper seal.
Can I upgrade to a better dome?
Yes. Many homeowners upgrade to a clearer, more weather-resistant polycarbonate dome.