Thermal insulation
Thermal insulation

Uw as low as 0.63 (Excellent)

Sound reduction
Sound reduction

up to 33-46dB (Good to Very Good)

Security
Security

up to RC 3

Locking
Locking

Fully Integrated

Construction depth
Construction depth

93mm

Test Certificate Available

bimobject.com

The KF 520 combines cutting-edge design with advanced performance, offering a sleek, frameless aesthetic that maximises natural light. From the outside, the sash is virtually invisible—creating a smooth, minimalist appearance that closely resembles fixed glazing.

Beyond visual appeal, the KF 520 leads in security with Internorm’s I-tec Secure system. This innovative technology uses integrated locking flaps that press into the frame on all sides when closed, achieving burglary protection up to RC3—making it one of the most secure windows in its class.

With Uw values of up to 0.63 W/m²K and sound insulation up to 46 dB, the KF 520 ensures optimal energy efficiency and acoustic comfort. It's the perfect choice for those seeking contemporary style, enhanced daylight, and complete peace of mind.

Features:

  • Material: uPVC interior, Aluminium exterior
  • Design: Lots of glass, plenty of light, invisible sash from the outside (glass design).
  • Security: Enhanced security up to RC 3 with I-tec Secure locking system (virtually impossible to lever out, integrated flaps).
  • Availability: Also available as a uPVC window.

Benefits:

  • Maximises natural light with its glass-focused design.
  • Offers a sleek and modern aesthetic with the invisible sash.
  • Provides exceptional security with the innovative I-tec Secure system.
  • Ensures excellent thermal insulation for energy efficiency and comfort.
  • Offers good sound insulation for a quieter home.

Homeowners looking for modern windows with a focus on maximising natural light and providing high levels of security.

  • Spec PDF
  • Surfaces & Colours
  • Handle Options
  • 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.

Expert Advice & Insights

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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 transform your home?

Our experienced team provides bespoke window designs and precision installations, ensuring every detail complements your architectural style.

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