Roof windows and skylights for flat roofs: how to choose the right one

For flat roofs you choose dedicated roof windows and skylights, because the pitch is very low: in the collection the models work between 0° and 15°, with some versions for 0°-5° and others for 2°-15°. The choice depends on what you need: light only (fixed), light and air (opening), or also an access point onto the roof (hatch). Sizes range from 60 x 60 to 90 x 120 and 70 x 140 cm.

The types

• Skylights with a clear dome: among the models is the DRC-C P2 skylight. On the data sheets the type is shown as "with clear dome".
• Flat-glass skylights: such as the DRF DU6 skylight or the DRG P2. The opening models are operated by hand or by motor: check on the data sheet whether the one you need opens.
• Fixed windows: such as the DXF DU6 and the DXC-C P2. They let in light only.
• DEF window: the DEF DU6 is a flat-roof window with flat glass.
• Hatch: the DRL hatch is used to get out onto the roof, for example for maintenance.

How to choose by job

The features to look at

• Roof pitch: ranges such as 0°-5°, 0°-15° and 2°-15°. It is the first figure to check.
• Dimensions: 60 x 60, 90 x 120 and 70 x 140. They correspond to the opening to be made in the roof deck or to the upstand.
• Window type: flat or with a clear dome. The dome projects, flat glass is more streamlined.
• Double glazing: with toughened outer glass or burglar-resistant.
• Walk-on: none of the models is walk-on: you cannot step onto the glass.
• Solar power: not available on any model in the collection.
• Warranty: 10 years, according to the collection data.
• Material and colour: white PVC frame. Suitable where you need a window that resists humidity and requires little maintenance.

Common mistakes

• Walking on the glass. The windows are not walk-on: to get up you need the hatch or a dedicated access.
• Fitting it without a kerb or upstand. It must be fixed to the roof deck, and the roof membrane is turned up at the sides.
• Not checking the drainage. Water must not collect on the glass.
• Choosing a fixed window when you need air. Then there is no way to ventilate.
• Forgetting to clean it. Seals and glass need cleaning periodically.
• Not thinking about the minimum pitch. Each model has its own range (0°-5°, 0°-15° or 2°-15°): if your roof is almost completely flat, do not choose a model that starts from 2°.

Frequently asked questions

What is the difference between a dome and flat glass?

The clear dome projects and helps water run off; flat glass has a more streamlined look.

What size do I need?

It depends on the room and on the opening you can make in the roof deck. The collection has three sizes: 60 x 60, 70 x 140 and 90 x 120 cm.

Can you walk on the glass?

No: in the collection data no model is walk-on. To get onto the roof, use the hatch.

Can I open it with a motor?

The opening models are operated by hand or by motor, depending on the version.

Is it also suitable for a slightly pitched roof?

Up to 15°, depending on the model. Beyond that you need roof windows for pitched roofs.

See all the models in the flat-glass roof windows collection: for pitch, size and type of opening, ask the AMES technicians for a quote or for advice.