Skylight Cost Calculator

Understanding skylight costs in Australia

What skylights cost in Australia in 2026

Skylight pricing splits cleanly into two markets. A tubular skylight, the reflective light tube that threads down between rafters and delivers a bright disc of daylight into a room, typically costs $650 to $1,200 supplied and installed for a standard 300mm to 400mm unit on a tiled single storey roof. A fixed glass skylight or roof window is a different proposition, generally $1,400 to $2,800 installed, and an openable venting roof window runs $2,200 to $4,000. Add an electric opener with a rain sensor, which closes the unit automatically when the first drops land, and you are looking at $3,000 to $5,500. Multiple units in one visit bring the per unit price down, often by 15 to 20 per cent on the second and subsequent skylights, because the access setup and site protection are already paid for.

Fixed, openable, or a light tube

The decision most people get wrong is buying a large glass skylight where a light tube would have done the job. If the goal is simply to get daylight into a dark bathroom, laundry, hallway or internal robe, a tube does that beautifully, costs half as much and requires no structural work at all because it fits between the existing rafters. Glass roof windows earn their price in living areas and kitchens where you want a view of the sky, a larger spread of light and, in the openable versions, real ventilation. An openable unit in a bathroom or above a stairwell is genuinely valuable, because hot air rises and a high level vent shifts steam and summer heat far more effectively than a wall window. The electric versions with rain sensors are a convenience purchase, but on a high ceiling or an unreachable stairwell they are the only practical way to have an openable unit at all.

Shaft length and why deep skylights disappoint

The distance from the roof plane to the ceiling plane is the variable people underestimate. On a raked or cathedral ceiling there is no shaft at all and the unit simply glazes the roof. In a standard house with a flat ceiling and a roof space above, the light has to travel down a shaft, and every metre of that journey costs brightness. Long shafts are worse still if they have to dogleg around a truss or a duct, because each bend absorbs light. A two storey shaft running from a top floor roof down to a ground floor ceiling can deliver considerably less light than the brochure suggests. If you are stuck with a deep run, keep the shaft as straight and vertical as possible, line it in the most reflective material available, and size up the unit rather than accepting a standard diameter.

Roof type, structure and the truss problem

The roof material sets the flashing method and therefore part of the labour. Tiles are the simplest case, since tiles lift out and a flashing kit sits into the batten line. Metal sheet roofing needs the sheet cut and a purpose made flashing dressed into the ribs, which is slightly dearer but very reliable when done properly. Slate is specialist work and prices accordingly. Flat and low pitch roofs are the difficult ones, because water does not run away, and any skylight on a membrane roof needs a raised upstand kerb and a properly terminated membrane detail. Structure is the other consideration. Most Australian homes built since the 1970s use prefabricated roof trusses, and truss chords are engineered members that cannot simply be cut. Anything wider than roughly 900mm generally means trimming a structural member, which needs an engineered detail and sometimes a certifier. A light tube avoids this entirely, which is a large part of its appeal.

Heat, glare and glazing specification

A skylight is a hole in your ceiling insulation, and it behaves like one. An uncoated single glazed unit facing west or north can admit enough solar heat through a summer afternoon to raise the room temperature noticeably and increase the air conditioning load, which quietly cancels out the lighting energy it saved. Specifying a low e coating, a double glazed unit or a tinted lens costs a few hundred dollars more and makes a substantial difference to both comfort and glare. In bedrooms, an internal blind is close to essential, because a skylight above a bed delivers full daylight from very early in a summer morning. Some tube systems include a dimmer or a closing diffuser for the same reason. Getting this specification right at purchase is far cheaper than retrofitting a blind into a finished shaft later.

Leaks, warranties and installer quality

Skylights have a reputation for leaking, and that reputation comes almost entirely from installation rather than product. A properly flashed skylight from a reputable manufacturer is as watertight as the rest of the roof and typically carries a ten year or longer product warranty. Problems come from units bedded in silicone rather than flashed, from flat roof installs with no upstand, from flashing that is not dressed correctly into the roof covering, and from general handyman installs where nobody owned the waterproofing. Insist the installer is a licensed roofer or an accredited installer for the brand, get the workmanship warranty in writing separately from the product warranty, and ask specifically how the flashing detail works with your roof material. That one question filters out a lot of operators.

Approvals, timing and getting a fair quote

Most single dwelling skylight installations do not need development approval, though heritage overlays and some strata schemes have a view about anything visible from the street or that alters the roof line, so check before you order. Building work still has to comply with the building code, particularly around structural alterations and waterproofing. On timing, a tube install is usually a half day and a glass unit one to two days, weather permitting, and no roofer will cut a hole in your roof with rain forecast. When comparing quotes, confirm the brand and model, the glazing specification, whether the shaft plastering and painting is included or excluded, and whether the price assumes a straight shaft. Those four items explain most of the difference between a cheap quote and a complete one.