Our catalogue has both uPVC and aluminium window systems, and aluminium comes in two kinds: thermally broken ("warm") and non-insulated ("cold"). Below is a comparison based on the published specs of Winklaus, VEKA, Deceuninck, Pimapen, Profilati and Asash systems: material, profile depth, glass, insulation and where each option fits. Price depends on the size and is calculated after a free on-site measurement.
| Feature | uPVC | Thermally broken aluminium | Cold aluminium |
|---|---|---|---|
| Frame material | uPVC profile with steel reinforcement | Aluminium with polyamide thermal bridges between the inner and outer parts | Aluminium without a thermal break |
| Profile depth in the catalogue | 58–80 mm | 55–95 mm; sliding systems 82 and 122 mm | 40–60 mm |
| Glass | Single 4 mm glass or 20–52 mm glass unit | up to 4-24-4 (AW55, AW65), up to 4-32-4 (AW73), up to 40 mm (RWT64), triple glazing — RWT95 | Single glass or a glass unit up to 4-12-4 (AW40) |
| Thermal and sound insulation | Good to very high: 3–7 chambers; VEKA soundproof window — Rw 36–40 dB | High; AW73 and RWT95 — for cold climates and near-passive-house projects | No thermal break — for mild climates, unheated and interior spaces |
| Large openings | VEKA portal system, VEKASLIDE sliding door | AKS 122 lift-and-slide — sashes up to 400 kg; AS82 sliding on 2 or 3 tracks | Shopfronts, partitions |
| Colour and finish | White, laminated (e.g. Sherwood G, Eiche Dunkel, Anthrazitgrau 7016), wood-look | Powder coating, anodising, wood effect | Powder coating, anodising |
| Best for | Flats, houses, offices — the main choice for homes | Villas, commercial buildings, large glazing, terrace doors, facades | Shopfronts, interior partitions, warehouses, ancillary rooms |
| In the catalogue | Winklaus 70, VEKA SoftLine 82, Deceuninck Nirvana, Pimapen S70 Maximus | Profilati AW65, Profilati AW73, Asash RWT64, Profilati AKS 122 | Profilati AW40, Asash RW60 |
The main difference is the frame material
A uPVC window is a multi-chamber plastic profile with steel reinforcement inside; the chambers are air cavities that hold heat. Aluminium windows come in two kinds: "warm", with polyamide thermal bridges separating the inner and outer parts of the profile (in Asash systems this is a PA 66 GF 25 insert), and "cold", without a thermal break. Cold aluminium does not keep heat in, so it is not used for living rooms.
When to choose uPVC
For flats and houses uPVC is the most common choice. The sweet spot is a 5-chamber, 70 mm profile (Winklaus 70, Pimapen S70 Maximus, Winsa Dorado, Evaks Leysan). For a noisy street, the VEKA window with Rw 36–40 dB sound reduction; for maximum energy efficiency, the 7-chamber Winklaus 75 or the 6-chamber Deceuninck Nirvana with glass units up to 52 mm.
When to choose aluminium
Thermally broken aluminium is chosen for large openings, terrace doors, commercial buildings and facades. The Profilati AKS 122 lift-and-slide system (122 mm) moves sashes of up to 400 kg with little effort, and the AS82 sliding system runs on 2 or 3 tracks and opens 2, 3 or 4 sashes. The 95 mm Asash RWT95 with triple glazing suits near-passive-house projects and withstands high wind loads. The profile comes in a wide range of anodised and powder-coated finishes.
Cold aluminium — only where heat does not matter
Profilati AW40 and 40C (40 mm) and Asash RW60 (60 mm) have no thermal break. They are used for shopfronts, interior partitions, warehouses and ancillary rooms in mild climates. A living room or a warm balcony needs uPVC or thermally broken aluminium.