Which kind of skylight do you need?
Tubular skylights use a small dome on the roof and a mirror-lined tube to bounce light down to a round diffuser in the ceiling. They suit hallways, bathrooms, laundries and walk-in robes, and they're the quickest to fit. More on our solar (tubular) skylights page.
Fixed skylights are a sealed glazed panel with a boxed light shaft built down through the roof space. They give much more light and a view of the sky, so they suit living areas and kitchens.
Opening skylights work the same way but open, by hand, motor or a solar-powered unit, to let out hot air and steam. They earn their keep over kitchens and bathrooms.
Roof windows sit in a raked or attic ceiling with no roof space above, so there's no shaft. See roof windows.
What installation involves
The installer marks the spot from inside, checks the roof space for rafters, wiring and ducts, then cuts the opening. On a tiled roof that means lifting and trimming tiles; on metal, cutting the sheet and supporting the cut edges.
The flashing is what keeps it dry. It's the metal or moulded collar that steers water around the skylight, and it has to match your roof profile. Velux, for one, says its flashings are designed to shed water without relying on sealants, which break down. Flashing smeared with silicone instead of fitted properly is the usual suspect when a skylight leaks.
Inside, a fixed skylight needs a shaft framed, lined, plastered and painted between roof and ceiling. That finishing is a big share of the price, and some quotes quietly leave it out.
Getting light without the heat
Go smaller than you think. Your Home, the federal government's guide to sustainable housing, says a skylight can let in more than 3 times the light of a vertical window the same size, and roof glazing takes in almost twice the heat of an unshaded west-facing window. It suggests about 3 to 5% of the floor area for a conventional skylight, or 1 to 2% for a tubular one.
Double glazing, tinted or low-E glass (a coating that reflects heat) and a blind all help. Ask the installer for the product's energy rating and which glazing they'd choose for your roof's direction.
Questions for the installer
- Which flashing kit suits my roof, and is it made for this skylight?
- Is the light shaft, plastering and painting included?
- What's in the roof space where you'll cut, and will anything need moving?
- Which glazing are you using, and how will it cope with summer sun?
- Who warrants the unit, and who covers a leak from the installation?
- Will an electrician be needed for a motor or to move wiring?
Your part, and the installer's part
You can
- Choose the spot from inside, thinking about where the sun falls through the day
- Shine a torch through the manhole to see what's above the ceiling, without climbing in if you're unsure
- Compare unit-only prices with installed prices before you pick a product
- Keep the manufacturer's paperwork for the warranty
Leave to a roofer
- Cutting the roof and fitting the flashing
- Framing, lining and plastering the shaft
- Moving rafters, wiring or ducts
- Any roof that might be asbestos cement, which needs assessing first
What we'd do
For a dark hallway, bathroom or laundry, we'd go tubular: cheaper, quicker and not much heat. For a living area where you want sky and plenty of light, we'd pay for a double-glazed fixed or opening unit and make sure the quote covers a finished shaft. Either way, we'd choose the installer on how they flash it, not on the brand of the unit. DIY tubular kits are sold, but fitting one means cutting into your roof, so we'd leave it to a roofer.
Want a roofer to take a look?
Tell us the job and your postcode. We match it with a Find My Roofer certified roofer who specialises in that kind of work, and they call you to quote. Your number goes to them alone.