Thermal insulation
Thermal insulation

Ud up to 0.87 W/(m²K)

Sound reduction
Sound reduction

up to 30 dB (-1;-2)

Security
Security

up to RC2

Locking
Locking

Multi-locking

Construction depth
Construction depth

93mm

Test Certificate Available

bimobject.com

The AT 525 aluminium front door brings a refined, architectural look together with proven performance. A rigid 93 mm construction and insulated core support Ud values down to 0.87 W/m²K, while three perimeter gaskets help maintain a reliable seal.

Built for busy homes and exposed locations, the full aluminium construction offers excellent weather resistance and low maintenance. Security comes as standard thanks to multi-point locking and options up to RC2.

Features:

  • Material: Full aluminium door and frame for high durability.
  • Construction depth: 93 mm with insulated core for thermal stability.
  • Sealing: 3 perimeter gaskets for consistent airtightness.
  • Opening: Inward opening (outward opening not available on this model).
  • Threshold: Thermally broken threshold to reduce cold bridging.
  • Security: Multi-point locking; performance options up to RC2.

Benefits:

  • Energy conscious: Ud as low as 0.87 W/m²K helps cut heat loss.
  • Quiet comfort: Sound reduction up to 30 dB (-1;-2).
  • Lasting strength: Aluminium resists warping and severe weather.
  • Low upkeep: Easy-clean surfaces and no periodic painting.
  • Security peace of mind: Robust multi-locking with RC2 options.
  • Clean lines: Slim, modern aesthetics suit contemporary façades.

Ideal for homeowners and architects seeking a slim, secure, and low-maintenance aluminium entrance with credible thermal performance. The AT 525 balances everyday durability with a crisp, contemporary appearance.

  • Spec Sheet
  • Colours & Surfaces
  • Obscure Glass Options

Recent Work

Working closely with architects, builders, and homeowners, we’ve delivered systems that combine thermal efficiency, modern aesthetics, and long-term durability—across private residences, sustainable developments, and architect-led designs.

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New Product Alert: HF 520 & AT 525 Now Available

We’re excited to introduce the new HF 520 Studio timber-aluminium window with I-tec Glazing, and the AT 525 aluminium entrance door to our premium Internorm range. Perfect for both residential and commercial projects, these new additions are now available to explore at our Brasted showroom.

Build It Live South East

Yes, we recommend booking an appointment to ensure personalised service and availability. You can schedule your visit by filling out our contact form or emailing us at [email protected].

During your visit, our team will guide you through our range of premium window and door systems. We’ll answer your questions, help you explore customisation options, and assist in finding the perfect solution for your project.

Absolutely! Bringing your project plans or drawings can help our team better understand your needs and provide tailored recommendations.

Our knowledgeable team is here to help. Whether you need advice on materials, styles, or energy efficiency, we’ll guide you through the process and ensure you make an informed decision.

Ready to Upgrade Your Garage Door?

Book your free home survey today and discover the perfect fit for your property.

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