PVC or Aluminium Windows? The Definitive Guide 2026

PVC or aluminium: the short answer

After over 25 years installing PVC and aluminium windows on the Costa Brava and Girona, my answer is clear: for most homes, PVC offers better value for money. It insulates more, costs less and requires no maintenance.

But 'most' doesn't mean 'always'. Aluminium has real advantages in certain projects: large-scale facades, commercial buildings, minimalist aesthetics with ultra-slim profiles. There is no universally better material — there is a more suitable material for each project.

In this article I give you all the technical data so you can make an informed decision. And at the end, I share something very few people consider and which, in my experience, is more important than the material: who fabricates and who installs your window. I explain it in detail in this article on manufacturer, fabricator and installer.

Thermal insulation: PVC wins by a mile

Thermal insulation is measured by the Uf value (profile transmittance, in W/m²K): the lower, the better. Here PVC has an undeniable physical advantage: PVC is a poor heat conductor by nature, while aluminium is one of the best thermal conductors in existence.

For aluminium to insulate reasonably, it needs a thermal break (TB) — a polyamide barrier that interrupts heat conduction through the metal. Even so, the best aluminium profiles with TB cannot match the values of a good PVC profile.

In real numbers: A mid-range PVC profile like Kömmerling 76 AD has a Uf of 1.2 W/m²K. A mid-range aluminium with TB sits around 2.5–3.0 W/m²K. And a high-end PVC like Kömmerling 76 MD PassivHaus goes down to 1.0 W/m²K.

What does this mean on your energy bill? In a home with 8–10 windows on the Costa Brava, the difference between PVC and aluminium with TB can mean savings of €200–400/year on heating and air conditioning. Over 10 years, that is €2,000–4,000.

Sound insulation: PVC also wins, but glazing rules

Sound insulation depends 70–80% on the glazing and only 20–30% on the profile. That said, PVC has the edge here too: as a denser material with sealed air chambers, it dampens vibrations better than aluminium.

With the same insulating glass, a PVC window typically gains 2–4 dB of sound reduction over aluminium with TB. It may seem little, but in acoustics every 3 dB halves the perceived noise. For more detail on glazing, see our article on the best glass for your window.

Professional tip: If silence is your priority, invest first in good acoustic glass (laminated with acoustic PVB) and then choose PVC as the profile.

Prices: PVC more affordable, aluminium pricier

PVC is more affordable than aluminium of equivalent performance. The average difference is 20–35% in favour of PVC.

Indicative prices for a standard window (100×120 cm, tilt-and-turn) installed in Girona, VAT included:

• Basic PVC (Cortizo COR-70): from €280
• Mid-range PVC (Kömmerling 76 AD): from €350
• High-end PVC (Kömmerling 76 MD / Veka Softline 82): from €420
• Mid-to-high PVC installed (with premium glass and hardware): from €600
• Mid-range aluminium with TB (Cortizo COR-70 RPT): from €450
• Premium aluminium (Schüco AWS): from €650

Remember these prices include professional fabrication and installation. You may find cheaper quotes, but first ask who fabricates the window. More info in our article on manufacturer, fabricator and installer.

For a quote with exact measurements, use our online price calculator.

Durability and maintenance

Both materials are very durable, but behave differently over time:

PVC — 40–50 year lifespan

• Zero maintenance: Cleaning with soap and water is all it needs.
• Corrosion-proof: PVC is inert to moisture, salt and acids. On the Costa Brava, with its salty air, this is a huge advantage.
• Colour stability: With technologies like Kömmerling Full Cover, colour guarantee reaches 15 years.

Aluminium — 30–40 year lifespan

• Sensitive coating: Powder coating can degrade under intense sun (chalking). On the Costa Brava we see aluminium profiles with degraded coating after 15–20 years.
• Possible corrosion: In salty environments, aluminium can suffer galvanic corrosion if the coating is damaged.
• Greater structural rigidity: An advantage for very large windows requiring less reinforcement.

Verdict: PVC requires less maintenance and ages better in a Mediterranean climate.

Aesthetics and finishes: increasingly equal

Historically, aluminium won on aesthetics with its slimmer profiles. But PVC has closed the gap enormously:

PVC — aesthetic evolution

• Increasingly slim profiles: Modern 76 mm systems feature frames with concealed glazing beads.
• 76+ colours available: The NaturKolor76 range from Kömmerling includes wood effects, metallics, solids and textured finishes.
• 3-side Full Cover: Kömmerling is the only manufacturer to laminate all 3 visible sides of the profile. More info here.

Aluminium — premium aesthetics

• Ultra-slim profiles: Aluminium's main aesthetic advantage. Systems like Schüco offer minimal frame sections with maximum glass.
• Unlimited RAL coating: Any RAL colour is possible with powder coating.
• Minimalist look: For modern facades with clean lines, aluminium remains the benchmark.

When to choose PVC

PVC is the best choice when:

• You prioritise thermal and sound insulation — PVC insulates more than aluminium across all price ranges.
• You want the best value for money — at equivalent performance, PVC costs 20–35% less.
• You want zero maintenance — PVC needs no painting or treatment.
• You live in a coastal area — total resistance to moisture and salt. On the Costa Brava this is our main recommendation.
• You seek energy efficiency — the only PassivHaus-certified systems at an affordable price are PVC.

Check our ranking of the 6 best PVC window manufacturers to compare brands.

When to choose aluminium

Aluminium is the best choice when:

• You need ultra-slim profiles — on facades where minimalist aesthetics are the priority.
• Very large windows — for glazed panels over 3 metres, aluminium rigidity is a structural advantage.
• Commercial or industrial projects — aluminium better withstands impacts and heavy public use.
• Matching existing aluminium — if your home already has aluminium on the main facade.

Can you mix PVC and aluminium in the same home?

Yes, and it is more common than you might think. In many of our projects we combine both materials:

• Main facade with large aluminium glazing + rest of the home in PVC.
• Living areas in PVC (lounge, kitchen) for sound insulation + commercial areas in aluminium.
• Wood-effect PVC inside + coated aluminium outside for facades with colour regulations.

The key is placing each material where it adds the most value.

My professional opinion after 25 years

I have been installing windows of all materials for over 25 years. And what this experience has taught me most is that the material matters less than people think.

What matters more? Who fabricates the window and who installs it. I explain it in depth in this article on manufacturer, fabricator and installer.

My advice: Choose PVC unless you have a specific reason to choose aluminium. Within PVC, pick a leading brand (Kömmerling, Veka) and, above all, ask who fabricates and installs your window.

Conclusion

PVC is the better option for most homes thanks to its superior insulation, lower price and zero maintenance.

Whatever your choice, the most important thing is working with a good fabricator and professional installer. At Instal Tancaments we can advise you on your project on the Costa Brava and Girona.

FAQs: PVC or aluminium

Which insulates better, PVC or aluminium?

PVC insulates better both thermally and acoustically. A mid-range PVC profile (Uf ~1.2 W/m²K) insulates twice as well as aluminium with TB (Uf ~2.5–3.0 W/m²K).

Which is cheaper, PVC or aluminium?

PVC is 20–35% more affordable than aluminium at equivalent performance. A mid-range PVC window starts at €350 installed; the equivalent aluminium with TB from €450. A mid-to-high PVC window installed starts at around €600.

Does PVC turn yellow in the sun?

No. Modern PVC profiles from brands like Kömmerling or Veka include UV stabilisers that prevent yellowing. Colour guarantee reaches up to 15 years.

Is aluminium stronger than PVC?

Aluminium is more rigid, which is an advantage for very large windows. But PVC with galvanised steel reinforcements is strong enough for 95% of residential windows.

Can PVC windows look like wood?

Yes. Brands like Kömmerling offer up to 76 colours including wood effects with Full Cover technology that laminates all 3 visible sides.

Can I mix PVC and aluminium in my home?

Yes. It is a common solution: aluminium on facades needing ultra-slim profiles and PVC in the rest of the home.