Aluminium, timber or steel: which frame for your roof lantern?

For a roof lantern on a house, thermally broken aluminium is in most cases the most practical choice: light, strong, low maintenance and available in any RAL colour. Timber has a warm look but needs maintenance. Steel gives the slimmest lines, but it is heavy and expensive. DagLichtDesign makes its roof lanterns from aluminium. Below you can read why, and when a different material may still suit you.

Aluminium roof lantern: light, strong and stable

Aluminium is light yet stiff enough to carry large glass panels. It does not rust: in air it forms a thin oxide layer that protects the metal. With a coating in a RAL colour it keeps its colour for a long time and only needs cleaning.

The drawback of aluminium is that it conducts heat well. A frame made in one piece would be a thermal bridge. That is why DagLichtDesign works with a thermally broken frame: an insulating strip between the inner and outer sections. This keeps the inside warm and prevents condensation on the profile.

• Low maintenance, cleaning only
• Any RAL colour, dual colour too
• Thermally broken against thermal bridging
• Light enough for an existing flat roof, if the structure allows

Timber roof lantern: warm, but with maintenance

A timber roof lantern suits a classic house, a garden room or an interior with a lot of wood. Timber insulates well in itself and feels warm inside.

The other side is maintenance. A timber frame on a flat roof gets full sun, rain and sometimes standing water on the bottom rail. Expect regular painting and check the joints and underside every year. If maintenance slips, moisture gets into the timber, and you often only see it when it is too late. For a conservatory or garden room with timber frames, you can also choose aluminium in a matching RAL colour.

Steel roof lantern: slim and industrial

A steel roof lantern has the narrowest profiles and suits the industrial look of steel internal doors and pivot doors. Steel is very strong, so a little material spans a lot.

Steel is, however, about three times as heavy as aluminium, conducts heat and needs good protection against rust. Thermally broken steel systems exist, but they are expensive and specialised. If you want the look of steel, an aluminium frame in RAL 9005 jet black or matt black gives a similar graphic effect, with less weight and maintenance.

The three materials side by side

In short, it comes down to this:

The frame is only a small part of the surface. Whether your roof lantern stays warm depends mainly on the glass, HR++ double glazing or triple glazing, and on a well-insulated upstand.

• Aluminium: light, low maintenance, any colour
• Timber: warm and well insulating, regular painting
• Steel: the slimmest, but heavy, expensive and prone to rust
• With all three, the glass does most of the insulating

Why DagLichtDesign makes aluminium

In its own factory in Barneveld, every roof lantern is made to measure with a thermally broken aluminium frame. Aluminium makes large panels possible, such as a mono-pitch roof lantern up to 5 metres wide without a glazing bar. It also allows short lead times: from 2 weeks after approval, with the lean-to in 1, 2 and 3 metres always in stock.

For contractors, aluminium means a product that is light enough to handle and needs no painting after handover. More on this at roof lanterns for contractors.

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