PVC or aluminium for your nZEB home? Complete technical guide 2026: real Uw, total cost, durability and usage scenarios. Clear answer for each situation.
What is an nZEB Home and Why Does Window Choice Matter
nZEB (Nearly Zero Energy Building) is the mandatory standard for all new constructions in Romania since 2021. Primary energy consumption ≤ 100 kWh/m²/year. Windows represent 15-25% of the envelope and account for 25-40% of total heat losses.
Real Differences: PVC vs Aluminium
PVC (Salamander bluEvolution 92): λ = 0.17 W/(mK) | Uf = 0.95 W/(m²K) | Uw with triple + Warm Edge: 0.72 W/(m²K)
Aluminium (Alumil S77 Supreme): 34 mm polyamide thermal break | Uf = 1.3 W/(m²K) | Uw: 1.0-1.2 W/(m²K)
Full Comparison Table
| Feature | PVC Salamander bluEvolution 92 | Aluminium Alumil S77 Supreme |
|---|---|---|
| Uw with triple glazing | 0.72 W/(m²K) | 1.0-1.2 W/(m²K) |
| Profile Uf | 0.95 W/(m²K) | 1.3 W/(m²K) |
| Acoustic Rw (dB) | 42-47 | 38-42 |
| Visual profile width | 70-82 mm | 30-45 mm |
| Large glazed areas | Limited | Excellent |
| nZEB recommendation | Ideal | Acceptable |
| Passive house | Ideal | Limited |
| Relative cost | Lower | +20-35% |
What Really Matters for nZEB Windows
Uw = (Ag × Ug + Af × Uf + lg × Ψg) / (Ag + Af)
Priority order: 1) Triple glazing + argon (Ug=0.5) 2) Warm Edge spacer (Ψg=0.03) 3) Profile type 4) Low-E coating 5) Installation quality
When PVC and When Aluminium
- Apartment renovation: PVC bluEvolution 82/92 — Uw = 0.72, 20-30% cheaper than aluminium
- Premium villa: Mix PVC (bedrooms) + Aluminium (large living area)
- Passive house PHI: PVC bluEvolution 92 + Blaugelb preframes — only option under Uw 0.8
- Commercial, facades: Aluminium Alumil S77/SF85
- Large sliding doors >3m: Aluminium Alumil Smartia M19800
FAQ
Which is more energy efficient? PVC — Uw = 0.72 vs 1.0-1.2 for aluminium.
What Uw for nZEB? Romanian standards: Uw ≤ 1.0 W/(m²K) Zone II (Bucharest). Passive house: ≤ 0.8.
Does modern aluminium still condense? No — with 34mm thermal break + Warm Edge + correct installation.
Is triple glazing worth it? Always for nZEB — saves 50% heat loss vs double. Payback 5-8 years.
Conclusion
| Scenario | Recommended | Reason |
|---|---|---|
| Apartment renovation | PVC bluEvolution 82 | Best Uw, cost-efficient |
| New standard home | PVC bluEvolution 92 | nZEB with safety margin |
| Passive house PHI | PVC + Blaugelb | Only option under Uw 0.8 |
| Villa with large living | Mix PVC + Aluminium | Right material in right place |
| Offices, facades | Aluminium Alumil S77 | Structure + aesthetics |
Related: Complete nZEB System | nZEB Windows Guide Romania | Salamander Prices 2026
Neofort BIZ supplies Salamander (PVC) and Alumil (aluminium) in Bucharest and Ilfov. Request free consultation.
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