Average Skylight Installation Cost in 2026 (UK)

Most UK skylight installations in 2026 cost £900–£2,500 per window, fully fitted. A small manual VELUX centre-pivot starts from around £650 installed, flat-roof skylights typically run £1,000–£3,000, and roof lanterns £2,000–£5,000+. Once scaffolding or structural alterations are involved, complex jobs can pass £4,000.

Those figures are drawn from 2026 trade cost guides — MyJobQuote’s skylight guide (updated June 2026) and BookaBuilderUK’s 2026 price data — plus retailer pricing, checked July 2026. For a range configured to your project, try the instant cost calculator.

Installed cost by skylight type

If you’re weighing up a fixed skylight against an opening roof window, the window itself is usually the smaller share of the gap — opening and electric versions cost more to buy, not much more to fit.

What you’re actually paying for

A “fitted skylight” quote bundles several line items. Knowing them makes quotes comparable:

Labour breaks down to roughly £200–£350 a day for the roof work itself, more for structural carpentry if the opening cuts through rafters. A straightforward install is a one-day job for a two-person team; see the timescales in the FAQ below.

The scaffolding question

Scaffolding is the swing factor nobody budgets for. Ground-floor rear extensions can sometimes be worked from towers or ladders; anything above that, or over a conservatory, usually means £400–£1,200 of access costs before a tile is lifted. Ask every installer whether their quote includes access — it’s the most common source of “surprise” overruns.

What moves the price

• New opening vs replacement. Cutting a new hole means structural work, interior finishing and building regs sign-off. A like-for-like swap into an existing opening runs £500–£800.
• Size. Bigger units cost more to buy and need more roof alteration. Doubling the glass area roughly doubles the supply price.
• Roof type. Pitched tile roofs are the standard case. Flat roofs need upstands; slate and conservation-grade materials cost more to work with.
• Spec. Electric or solar opening adds £300–£800; triple glazing adds £150–£400.
• Where you live. London and the South East sit at the top of every range above.

A custom or non-standard skylight sits outside these ranges entirely — glazing made to order can cost several times the price of a standard unit.

Permissions and regulations

Most skylights are permitted development — no planning application needed — provided they don’t project more than 150mm proud of the roof plane. Listed buildings and conservation areas are the exceptions; our skylight planning permission guide covers the details.

Building regulations are a separate matter and do apply to new openings, covering the structural alteration and thermal performance. Use an installer registered with a competent person scheme (FENSA or CERTASS for windows) and they self-certify — no separate building control fee.

How to keep the cost down

1. Get at least three itemised quotes. Ranges this wide mean quotes vary hugely for identical work. Insist on supply, labour, access and finishing as separate lines.
2. Pick standard sizes. Made-to-measure glazing is the fastest way to double a budget.
3. Batch the work. Two windows fitted on the same visit share the scaffolding and call-out cost — the second unit is always cheaper than the first.
4. Manual over electric where you can reach. The £300–£800 premium for powered opening buys convenience, not light.
5. Don’t buy purely on price. A poorly flashed skylight leaks, and re-doing flashing costs more than doing it right once. Check references and guarantee terms — whether the window itself is worth the spend matters less than who fits it.

Prices are typical quoted figures including VAT from the sources above; trade quotes sometimes exclude it — always confirm.