Which insulates better, uPVC or aluminium windows?

With the same triple glazing, a good uPVC profile usually insulates slightly better than an aluminium one. The best thermally broken aluminium systems come very close, though.

Are aluminium windows more expensive than uPVC?

For the same size, aluminium usually costs more than uPVC. The gap depends on the dimensions, the system and the options, so only a quote after measuring gives a reliable figure.

Can I mix uPVC and aluminium windows in one house?

Yes. Many houses combine uPVC windows with a large aluminium sliding door, in the same colour on the outside.

uPVC vs aluminium windows: which to choose?

uPVC vs aluminium windows: which is better for your home?

For most houses in Luxembourg, uPVC gives the best insulation for the budget and needs almost no maintenance. Aluminium makes sense for large glazed openings, very slim frames and contemporary architecture. Both perform very well with triple glazing, as long as the profile system is good and the installation is done with care.

By Marcio Barros · Updated 31 October 2026 · 6 min read

uPVC vs aluminium at a glance

	uPVC	Aluminium
Thermal insulation	Very good	Very good with a thermal break
Frames	Wider	Slimmer, more glass
Large sizes	Limited	Very large openings possible
Colours	Colour foils, woodgrain finish	Any RAL colour
Maintenance	Almost none	Almost none
Cost for the same size	Lower	Higher

Which is more energy efficient?

uPVC is a natural insulator, and its frames are divided into several chambers. Aluminium conducts heat, so it needs a thermal break: an insulating barrier in the core of the profile. With a good system and triple glazing, both materials can reach the values required for Klimabonus, the Luxembourg grant for energy renovation.

Which is better for noise?

Noise comes through mainly via the glazing and the seals, not the frame. If your home is near a busy road or a railway line, the choice of acoustic glazing matters far more than the frame material. See our guide to soundproof windows.

uPVC vs aluminium windows: the cost difference

For the same size, an aluminium window usually costs more than a uPVC one: the material, the thermal break and the powder coating add steps. We do not publish prices, because every window is made to measure. Our window prices guide explains what drives the cost.

Style and light

uPVC suits almost any house, in white, anthracite grey or a woodgrain finish.
Aluminium gives slimmer lines and more glass. It is popular for contemporary homes and large glazed openings.

Our advice

Existing house, standard-size windows: triple glazed uPVC, anthracite outside if you like a modern look.
Large openings, contemporary architecture: aluminium, at least for the large openings.
A mix of both: uPVC windows and an aluminium sliding door, in the same colour on the façade.

See our uPVC windows and aluminium windows, or ask for advice during the free measurement visit.

ExploreuPVC and PVC windows in Luxembourg