Flat and low-pitch roofs over extensions, garages and modern homes need a different kind of skylight. Water moves slowly on a near-flat surface, and in heavy rain it can sit in a shallow sheet across the roof. A standard pitched-roof skylight simply cannot cope, so flat roof skylights in Wellington sit on a raised kerb that lifts the glazing well clear of the roof surface.
Getting this right in Wellington means planning for ponding, wind-driven rain and the way the membrane or roofing meets the kerb. We install domes, pitched glazed units and roof lanterns on flat and low-pitch roofs, and we integrate each kerb with the waterproofing so the joint is as strong as the rest of the roof. Our skylight overview covers how these differ from pitched roof units.
We install acrylic domes, glass lanterns and walk-on rooflights on flat roofs, bringing generous natural light into extensions, kitchens, offices and commercial spaces, using quality materials, proven methods and careful planning.
Flat roof skylights need raised upstands and correct membrane integration to avoid leaks. We build kerbs and detail waterproofing carefully for lasting, trouble-free performance, with clear communication and honest advice.
Modern flat roof skylights include thermally broken frames and double glazing, helping reduce heat loss and condensation while delivering plenty of daylight to interior spaces, by an experienced local team.
The right choice depends on the look you want, how much light the space needs and how the roof drains.
A curved acrylic or polycarbonate dome sheds water naturally and suits garages, workshops and utility areas. Double-skin domes reduce heat loss and condensation compared with older single-skin versions.
Flat glass must slope to shed water, so it sits on a kerb or frame built with a small fall. Lying perfectly flat, glass collects dirt and water, which streaks and can find a way past the seals.
A lantern is a glazed, pitched structure that sits on the flat roof like a small glass roof. It adds height and a lot of daylight to a kitchen or living extension, and needs a sturdy kerb and careful detailing.
Some units are made for flat roofs with an integrated upstand, which simplifies the joint with the membrane. They suit modern homes where a minimal look from inside and outside is wanted.
Many domes and flat glazed units come in an opening version, usually electric with a rain sensor since they sit out of reach. They let steam and heat escape from kitchens and bathrooms under a flat roof.
Where a flat-roofed hallway or bathroom needs light but not a view, a tubular skylight on a low-pitch base is a compact option. The small opening keeps the cut into the membrane or roofing to a minimum.
The kerb, or upstand, is a framed box around the opening that raises the skylight above the finished roof surface. It needs enough height that ponding water and rain blown across the roof cannot reach the top, and it must be built from treated timber or a factory-made upstand, insulated to reduce condensation inside the shaft.
Roof falls around the kerb matter just as much. On the upslope side, water can collect against the kerb unless the roof is shaped to move it around. On larger kerbs we form a small cricket, a raised section that splits the water flow to either side, so it never sits against the upstand.
On butynol, TPO and torch-on roofs, the membrane is turned up the face of the kerb and finished under a capping, with corners reinforced because that is where membranes are most likely to split. Adhesives and primers must be compatible with the membrane, and the joint is designed to meet Building Code clause E2 External Moisture. Our membrane roofing page explains these systems in more detail.
Adding a skylight to an existing membrane roof means cutting into the waterproofing, so we assess the membrane's condition first. If it is near the end of its life, it may make sense to plan the skylight alongside flat roofing repairs or replacement, so the new kerb is integrated with sound waterproofing.
Low-pitch long-run metal roofs, common on extensions and some 1960s and 70s homes, also call for kerb-mounted units. The sheet above the kerb is stop-ended and a wide back flashing carries water around the upstand to the sheets below. Because water moves slowly at low pitch, the flashing has to be generous, and we follow the NZ Metal Roof and Wall Cladding Code of Practice for the detail.
Flat roof skylights are demanding because water does not run off them as quickly as it does from pitched roofs, so every detail must be right. Our installers build raised kerbs, integrate membranes carefully and fit domes, lanterns or walk-on rooflights that suit your building. We consider thermal performance, condensation and drainage from the start, choosing thermally broken frames and double glazing where appropriate. Whether you are lighting a home extension, kitchen, office or commercial space, we manage the roof, framing and waterproofing together so responsibility sits with one team. The finished skylight floods your space with daylight and stays watertight through Wellington's heaviest rain. Get in touch today.
Flat roof skylights are closely tied to the waterproofing around them, so these pages on membranes, flat roofing and larger roof lights are worth a look.
Call our team if you need advice for your property or roofing project.
04 888 0115Yes. The skylight sits on a raised kerb, and the butynol is turned up the kerb and finished under a capping. Corners are reinforced and adhesives are chosen to suit the membrane. We check the existing butynol's condition first, because cutting into an old, brittle membrane can cause more problems than it solves.
Usually because the roof falls do not direct water around the kerb, or the roof has deflected slightly over time. Water then sits against the upstand, which stresses the membrane joint. Adding a cricket on the upslope side, or correcting the falls, moves the water away. Clearing debris from outlets also helps.
It can be, with the right specification. A lantern needs a strong kerb, secure fixing into the roof structure and glazing suited to the wind zone. On very exposed sites we may recommend a lower-profile lantern or a pitched glazed unit instead, which presents less to the wind.
No. Treat any skylight as non-trafficable unless it has been specifically designed and rated as walk-on glazing. Falls through skylights are a recognised hazard, and WorkSafe guidance on working at height applies whenever people are on the roof. Where a flat roof is accessed regularly, we can discuss guarding or safety mesh around the opening.
Single-skin domes and uninsulated kerbs are the usual causes, because their cold surfaces sit directly above warm rooms. A double-skin dome or double-glazed unit, an insulated kerb and good ventilation in the room below all reduce it. Our skylight condensation fixes page explains the options.
Experience a top-notch roofing services wherever you are in Wellington. Get in touch with our team and will come back with you a free, no-obligation estimate for any roofing service.
