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Windows range · Aluminium

Aluminium windows: slim lines for large glazed surfaces

The choice for design and daylight. Thanks to slim, very rigid profiles, aluminium opens up large bays with maximum glass area. With a thermal break it delivers outstanding performance — the benchmark for contemporary extensions and architectural projects.

My free aluminium quote → Voir les prix indicatifs
Uf 1.4–1.8
with thermal break
50 years +
service life
XXL bays
large glazed surfaces
Aluminium windows: slim lines for large glazed surfaces
Ultra-slim profilesmaximum glass area
Unlimited RALevery colour
Technical specifications

What an aluminium window is really worth

The numbers that matter for quality aluminium joinery, fitted by our teams. Concrete benchmarks, not marketing.

  • Thermal insulation
    Uf 1.4–1.8 W/m²K

    Aluminium conducts heat: performance comes from the thermal break (an insulating strip between inside and outside). Paired with triple glazing, the whole unit (Uw) drops to the level of a high-performance build.

  • Profile slimness
    The slimmest

    Aluminium’s rigidity allows narrow frames and large opening sashes. The result: more glass area, more daylight and clean lines no other material can match.

  • Large dimensions
    XXL bays

    Sliders several metres wide, full-height windows, glazed roofs: aluminium carries surfaces PVC simply cannot. The material of architectural projects and glazed extensions.

  • Durability
    50 years +

    Aluminium does not rust, warp or fear UV. Powder coating protects the colour for the long haul. It is one of the most durable materials in exterior joinery.

  • Aesthetics
    Unlimited RAL

    The full RAL range, in matte, satin or textured finishes, and even two-tone (one colour inside, another outside). The contemporary look par excellence.

  • Maintenance
    Virtually none

    No painting or treatment. A wipe with soapy water is enough. Powder coating keeps its appearance for decades with no intervention.

* Indicative values for standard-range profiles with a thermal break. Exact performance depends on the model, glazing and dimensions — confirmed at the survey.

In full transparency

Aluminium: strengths & limits

No material is perfect for every project. Here, honestly, is where aluminium excels and where you should look elsewhere.

Where it shines

  • The slimmest profilesMaximum glass area and daylight, with contemporary lines.
  • Ideal for large baysCarries the very large glazed surfaces PVC cannot.
  • Exceptional durabilityUnaffected by rust, UV and warping for decades.
  • Every colour possibleFull RAL range, matte or textured finishes, and two-tone.

What to keep in mind

  • Pricier than PVCOften 30 to 40% above PVC for comparable performance.
  • Insulation depends on the thermal breakWithout a quality insulating strip, aluminium insulates poorly: the range matters.
  • Dark colours sensitive to the sunAnthracite and black heat up: we adapt the coating on south-facing aspects.
  • Manufacturing footprintAluminium is energy-intensive to produce — offset by its longevity and recyclability.
For which project

Is aluminium right for you?

It comes into its own whenever you want daylight, large openings and a contemporary style. A few cases where it shines:

  • Extension or large bay

    Extension or large bay

    Sliders several metres wide, glazed façades, conservatories: aluminium opens up wide without bulking the frames. Daylight on a grand scale.

  • Architectural / design project

    Architectural / design project

    For minimalist lines and slim frames to match contemporary architecture, aluminium is the benchmark material.

  • Commercial & large dimensions

    Commercial & large dimensions

    Offices, shops, apartment blocks: when openings are large and numerous, the rigidity and durability of aluminium make the difference.

Tighter budget, or a wood interior?

For the best insulation-to-price ratio on standard-size openings, the PVC window remains unbeatable. And for the warmth of wood inside with aluminium outside, take a look at .

AFTER photo — large aluminium sliding bay
BEFORE photo — small window and solid wall
Avant Après
Glissez la poignée pour comparer
Case study · extension, Waterloo

A wall opened onto the garden by a 4-metre aluminium bay

When extending a living room, the client wanted to erase the boundary between inside and the garden. We fitted a 4-metre aluminium slider with a thermal break and triple glazing: slim frames, maximum daylight and insulation on a par with a new build.

  • 4 msliding bay
  • Uw 0.9with triple glazing
  • −30%heat loss in the room
Customer reviews

They chose Wendows

5.0/5 · 7verified reviews

« Nous avons fait appel à la société Wendows pour le remplacement de nos châssis. La différence par rapport aux autres sociétés c'est qu'ils ont pris le temps de faire une étude complète et de nous proposer les châssis qui correspondaient à notre maison et notre besoin. Leur but n'était pas de mettre un châssis et de clôturer un chantier pour en faire un autre. Nous avons été accompagnés dans tout le processus. Du devis, en passant par la prise de mesure et l'attente de livraison. Délais respectés. Je ne peux que recommander cette société. Rapport qualité prix professionnalisme +5⭐️ »
Pierre Jérôme
« Nous avons fait appel à la société Wendows pour le renouvellement de nos châssis et nous sommes vraiment ravis du résultat ! Les travaux ont été réalisés dans les délais annoncés et la finition est impeccable. De plus, M. Aprile qui s'est occupé du devis, s'est toujours montré disponible pour répondre à toutes nos questions. Nous vous recommandons donc de faire appel à eux pour vos travaux ! »
Annick Hauteceur
« Excellente expérience avec Wendows ! Les nouveaux châssis ont transformé notre immeuble et réduit nos factures d'énergie. L'équipe est professionnelle, rapide et à l'écoute. Je recommande vivement leurs services pour toute optimisation énergétique. »
Miguel Cruz
See all reviews
Compare the options

Aluminium, or something else?

Aluminium wins on slimness, large dimensions and style. Compare it point by point with PVC and wood-aluminium, then open up the range that interests you.

Critère AluminiumVous êtes ici PVC windowsVoir la gamme →
Indicative price €€€ — higher The gentlest €€€€ — premium
Profile slimness The slimmest Standard Intermediate
Large bays Ideal Limited Very good
Thermal insulation Very good (thermal break) Excellent, natural Excellent
Maintenance Virtually none Virtually none Virtually none (aluminium outside)
Aesthetics / look Contemporary, clean Understated, 40+ colours Warmth of wood
Ideal for Large bays, design style Renovation, set budget Durable premium
Indicative benchmarks for standard ranges. The right choice depends on each opening — we fine-tune it together at the survey.
Indicative price 2026

How much does an aluminium window cost?

The price depends on dimensions, the type of opening, the glazing and the finish. Aluminium pays off most on large surfaces. Here are some benchmarks for fitted aluminium.

See the detailed aluminium price list →

* Indicative ranges per fitted aluminium window, excluding special configurations. A costed estimate is provided with your free quote.

  • Aluminium window
    from €650
    fitted tilt-and-turn, double glazing
  • Aluminium slider
    from €2,500
    2-sash bay, fitted
  • Renovation grant
    up to 35%
    of the amount, depending on your income
  • Reduced VAT
    6%
    for renovation (home > 10 years old)
Aluminium windows FAQ

Your questions about aluminium

Does aluminium insulate as well as PVC? +

Provided it has a quality thermal break. Aluminium naturally conducts heat; it is the insulating strip built into the profile that delivers performance. A serious aluminium range achieves excellent results, slightly behind PVC at equal budget, but with much slimmer profiles.

Why is aluminium more expensive? +

The material, the thermal break and the powder-coated finish cost more than PVC. The gap is justified on large bays and design projects, where aluminium’s slimness and longevity have no equal.

What size of bay does aluminium allow? +

Very large dimensions: sliders several metres wide, full-height windows, glazed façades. The metal’s rigidity allows opening sashes PVC cannot carry without thickening or heavy reinforcement.

Which colours are available? +

The full RAL range, in matte, satin or textured finishes, and even two-tone (one colour inside, another outside). Anthracite and black are the most requested for their contemporary look.

Does aluminium need maintenance? +

Virtually none. The powder coating protects the colour for the long term; a simple wipe with soapy water once or twice a year is enough. No painting or treatment to redo, unlike wood.

What grants apply to aluminium windows? +

Grants depend on the performance achieved (Uw coefficient), not on the material. A high-performance aluminium window qualifies — depending on your region and income — for a renovation grant and 6% VAT for homes over ten years old. We guide you step by step through the grant application.

Get your free aluminium window quote within 48h

Free on-site survey, grants calculated, a single point of contact. Describe your project in under a minute.

  • Free and with no obligation
  • Grants & 6% VAT explained for you
  • Fitted by our certified installers
Request my aluminium quote → 067 21 04 02