Are aluminium windows worth the extra cost? For a house with ordinary-sized windows, usually not: uPVC gives better insulation for less money. Aluminium earns its price on large glazed areas, slim frames, heavy sliding doors and any RAL colour. Both materials meet thermal requirements, and you can compare the price of both versions of the same project straight away in our configurator.
We sell made-to-measure uPVC and aluminium windows online and deliver regularly to Belgium, Germany, the Netherlands, France, Austria and Czechia, and to other EU countries once transport is agreed. We do not fit them: you pay for the product and choose your own installer. So we have no reason to push the more expensive material. If a cheaper system is enough, we will say so.
uPVC vs aluminium: comparison table
| Criterion | uPVC | Aluminium (Aluprof) | |---|---|---| | Thermal insulation | Kömmerling 88 MD Uw from 0.73, Salamander bluEvolution 82 Uw from 0.75 | MB-79N Uw from 0.95, MB-104 at passive house level | | Profile depth | 76–88 mm | MB-79N, MB-86, MB-104 (the number is the depth in mm) | | Glazed area | windows and doors in typical sizes | floor-to-ceiling glazing, corners without a post, heavy lift and slide doors | | Frame width | wider profiles | slimmer profiles for the same window size | | Colours | white at base price, foil outside or on both sides | any RAL colour, always the same on both sides | | Price for the same size | lower | higher | | Maintenance | wipe the seals, lubricate the hardware once a year, no painting | powder coating, hardware once a year as well | | Unheated spaces | not applicable | MB-45 without thermal break for interior partitions and unheated conservatories |
The Uw figures are “from” values for a reference window. Your window will have its own value, depending on size and layout.
When to choose uPVC
- When your windows are of typical sizes and insulation for the money matters most.
- When you want white windows, or a woodgrain, anthracite or grey foil outside with white inside.
- When you are renovating and want to fit the new window over the old frame without breaking out the plaster. A renovation frame is available in some systems, and the configurator shows which.
With uPVC, keep the colour in mind for the whole order: colour outside and white inside, or the same colour on both sides, one for all windows. We do not make two different colours on the two sides of a window.
Are aluminium windows worth the extra cost in your case?
- When you plan floor-to-ceiling glazing or a corner without a post.
- When the lift and slide doors are to be very large and heavy. MB-86 in its ST, SI and AERO versions is made for such glazing.
- When the frame should be as slim as possible and the colour any shade from the RAL chart.
- When the house is to be passive and large windows must hold heat: then MB-104.
MB-45 is a profile without a thermal break. It suits interior partitions, shopfronts and unheated conservatories, but not a heated house.
There is also a middle option
Kömmerling 76 MD AluClip and 88 MD AluClip are uPVC windows with an aluminium cover on the outside. Inside you have uPVC, from the street you see aluminium. This option combines uPVC insulation with an aluminium look on the facade. We cover the differences between the materials in more depth in uPVC or aluminium in figures, and large panes in our article on fixed, corner, lift and slide and tilt and slide glazing.
What to watch out for
Coloured tilt and slide (PSK) doors have a smaller maximum width than white ones. If the opening is wide and you want coloured uPVC, check the size in the configurator before settling on the material. A door sash can be at most 2300 mm high in both materials, so a taller opening gets a transom.
We have worked with windows since 1997, have more than 5,000 orders behind us and have shipped windows abroad since the late 1990s. When a customer sends a list and ticks two systems, say uPVC and aluminium, we price both and check sizes and opening sides in each. Then the price difference is worked out on your windows, not on a catalogue example.
Grant schemes have their own conditions and often require fitting by a contractor. Check the official website of the scheme or ask an adviser before you decide.
Price both materials on your own windows
Put your windows together in the configurator once in uPVC and once in aluminium, and compare the prices. The systems are described on our uPVC windows and aluminium windows pages. We prepare a quote with delivery within 3 working days. Before production you get a drawing to approve, and the GALI warranty on profiles, hardware and sealed units runs for 2 years.