Here, you’ll find handy breakdowns for how much you can expect to pay to install the most common types of flat rooflights and skylights. We’ve collected a ton of quotes from all across the country to give you a benchmark to work from, and we’ve grouped some common sizes based on our own range of rooflights.
Because we don’t fit them ourselves (we just supply them, with UK-wide delivery) we’ve built this guide to be as impartial as possible to help you find the right fitter at the right price.
You’ll find in this guide:
- A breakdown of average labour costs
- Extra costs you might incur
- Some tips for getting quotes
- Frequently Asked Questions
If you’re looking for a comprehensive guide to what flat rooflight you should choose, check out our post Best Skylights for Flat Roof: Complete Buying Guide.
You can also check out our flat rooflight price calculator, where you can input the size of your window, glazing type, glazing finish, and self-cleaning options and instantly get a cost estimate.
UK rooflight installation price estimates for 2025
Use the table below to help you estimate the cost to fit your flat rooflight. We’ve grouped the common rooflight sizes we sell into small, medium and large just to keep things a bit simpler.
| Size of Bottom Pane (mm) | Average UK Labour Cost |
| Small (400x600mm – 800x1300mm) | £300 – £,500 |
| Medium (900x1200mm- 1200x1900mm) | £500 – £800 |
| Large (1000x2500mm – 2100x400mm) | £800 – £1,500 |
| Custom / irregular size | £800 – £2,500 |
Extra costs
As well as the labour costs you’ll incur, you might have to pay for a few extra bits too. You can expect your fitter to include these in their quote, but it’s always worth asking for a full breakdown before you agree to the work.
Flashing Kit & insulation: £100 – £250
(A flashing kit is a weatherproof seal between the window and roofing)
Scaffolding: £300 – £800
(Scaffolding might not be necessary, depending on height and access)
Interior Plastering & Finishing: £150 – £350
(Your fitter might not provide this service, so you may need to hire a plasterer)
Tips for getting a quote
Here are a few handy tips for when you’re ready to start shopping around for quotes.
1. Give Detailed Specs: Clearly communicate dimensions, rooflight type, and any special considerations to avoid any unwanted surprises when they come to fit your rooflight.
2. Request a Cost Breakdown: Ask for a detailed quote that separates material costs, labour, and any additional work such as scaffolding. This makes it much easier to compare quotes between fitters.
3. Check Reviews and Reputation: Ensure your installer is experienced, insured, and knowledgeable about local building regulations. Check online reviews, and ask if they’ve got any photos of installs they’ve done that are similar to yours. Ask friends and neighbours to take a look at the quotes to see if they seem reasonable.
4. Get Multiple Quotes: Compare quotes from different fitters to assess pricing, service quality, and customer reviews. A higher price doesn’t always guarantee better work!
Installing a flat rooflight FAQs
What factors affect the price of fitting a rooflight?
Here are a few common considerations to factor in when shopping for quotes:
For the materials:
Size of the frame
- Custom sizing
- Double or triple glazing options
- Glazing finish (blue, grey, opaque, clear, solar control)
- Self-cleaning options
- Your location (delivery charges may vary)
For the labour:
- Having built-in blinds installed
- Access (scaffolding requirements)
- Any necessary modifications to roofing structure (reinforcing beams or changing roofing materials)
- Planning permission (generally only an issue for listed buildings or conservation areas)
- Your location (labour rates will differ somewhat depending on where you live)
How long does it take to install a flat rooflight?
In our experience, installing a flat rooflight typically takes between one and two days. This includes preparing the roof opening, fitting the rooflight, and applying proper sealing and weatherproofing.
Factors such as roof accessibility, the size of the rooflight, and weather conditions can influence the time it will take. When you get a quote, your fitter will give you a fairly accurate estimate based on similar jobs they’ve done.
Do I need planning permission to install a flat rooflight?
In the UK, installing a flat rooflight typically falls under permitted development rights, so you won’t need planning permission. However, certain conditions should be met:
- Projection: The rooflight should not extend more than 150mm beyond the existing roof plane.
- Height: It must not surpass the highest point of the roof.
- Side-Facing Windows: If the rooflight is side-facing and within 10.5 meters of a side boundary, it should be obscure-glazed and non-opening.
Planning permission may be needed if your property is a listed building, located in a conservation area, national park, World Heritage Site, or if it’s a flat or maisonette. If you’re unsure, it’s best to consult your local planning authority.
Can I fit my own flat rooflight or skylight?
While it is possible to install a flat rooflight yourself if you’re experienced and confident in handling structural modifications, it’s generally best to hire a professional. Hiring a fitter ensures compliance with building regulations and means a safer, more reliable installation, ultimately saving time and hassle.
Choose Toughened Glass Systems for your flat rooflight
Our flat roof skylights flood your space with natural light and create a seamless connection with nature. Our most popular product, they’re great for contemporary or traditional houses, and open up your space to create a welcoming environment all year round.
Flat rooflight cost calculator
Now you know all about how much it’s likely to cost you in labour, use our cost calculator on our flat rooflight page to price up the materials! If you’re unsure about anything, you can always get in touch with our helpful and super experienced team.
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- Can You Install a Rooflight on a Flat Roof?
- Rooflight and Skylight Cost: A Complete Guide
- Flat Roof Extensions – A Complete UK Guide for 2025