Aluminium vs uPVC Windows: Which Is Better for Your Project?.

The debate.

Architects, builders, and homeowners frequently face the choice between aluminium and uPVC (unplasticised polyvinyl chloride) windows. Both have evolved significantly, but they serve different priorities.

Structural strength.

Aluminium wins. Aluminium's strength-to-weight ratio allows slimmer profiles that hold larger glass panels. A typical aluminium frame can support glass up to 200mm thick, while uPVC frames require bulkier profiles to achieve the same structural rating.

For large openings — floor-to-ceiling sliding doors, curtain walls, and panoramic windows — aluminium is the only viable option.

Thermal performance.

Tie — with caveats. Raw uPVC has lower thermal conductivity than raw aluminium, but modern thermally-broken aluminium systems (using PA66GF25 strips) close this gap entirely. PINDÉ's A120 system achieves Uw values below 1.0 W/m²K — matching or exceeding most uPVC systems.

The key is the thermal break: without it, aluminium loses. With a quality thermal break, aluminium matches uPVC while offering superior strength.

Aesthetics & design freedom.

Aluminium wins. Slim sightlines (as narrow as 50mm) maximise visible glass area. Aluminium accepts powder coating in any RAL colour, anodised finishes, and wood-grain effects. uPVC is limited to white, grey, black, and a few laminate options — with visible welding marks at corners.

For premium architectural projects, aluminium delivers the clean, precise aesthetic that uPVC cannot match.

Lifespan & sustainability.

Aluminium wins. Aluminium windows last 40–60 years with minimal maintenance. uPVC degrades under UV exposure, yellowing and becoming brittle after 20–30 years. Critically, aluminium is 100% recyclable without quality loss, while uPVC recycling is limited and energy-intensive.

Cost.

uPVC wins on upfront cost. uPVC windows are typically 20–40% cheaper to purchase. However, when factoring in lifespan (2× longer for aluminium), maintenance costs (lower for aluminium), and resale value impact, aluminium's total cost of ownership is often lower.

When to choose each.

Bottom line.

For premium residential, commercial, and architectural projects, aluminium with thermal break technology is the superior choice. uPVC remains competitive for budget residential projects where design flexibility is secondary.