The Heritage Glazing Authority

We invented ultra-thin double glazing for listed buildings.

Complete Conservation Service

From planning applications to final installation, we're with you.

Unmatched Certification Standards

One of only two UK companies holding full BS EN 1279 Parts 1-6 certification.

Authentic Slim Sightlines

Preserve architectural integrity with 6mm sightlines – the slimmest available.

The Science Behind Krypton Windows 

Standard double glazing relies on Argon, but for the uncompromising requirements of a listed building, Argon simply cannot compete. Krypton is a rare noble gas, significantly denser than the air we breathe and the common gases used by our competitors. This density allows us to achieve superior thermal insulation in cavities below 10mm – the exact precision required for authentic slim sightlines.

By significantly lowering thermal conductivity, SlimLite™ Krypton units create a formidable barrier against heat loss. For homeowners in conservation areas, this technology offers the pinnacle of performance without the unsightly, bulky profiles of modern triple glazing.

Superior Insulation Through Advanced Noble Gas Technology

Krypton isn't just an alternative; it is the definitive choice for heritage applications. Where standard glazing fails to provide adequate thermal retention in narrow spaces, Krypton excels. Its molecular structure reduces heat transfer to a minimum, ensuring your period home remains a sanctuary of warmth.

  • Dominant insulation in ultra-narrow cavities

  • The definitive choice for sensitive heritage restoration

  • Year-round protection against heat loss

  • Upholds the integrity of original slim window profiles

sash windows and bifold door

The Definitive Choice for Heritage Professionals

Choosing the right gas fill is a matter of technical necessity, not just preference. Krypton is the industry-leading choice for heritage projects because it delivers maximum energy efficiency within the strict physical constraints of slim sightlines.

Whether your project involves delicate sash or classic casement windows, our Krypton-filled units balance thermal excellence with historical compliance. It’s the only choice for those who demand efficiency without sacrificing aesthetic heritage.

Request Your Technical Quote

Contact our knowledgeable team today to discuss specifications, performance requirements, and obtain competitive pricing for your project.

"Great service along with a quality product, also the best advice on the different types of the slimlite range."

Martin

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"Great high quality product, does exactly what it is supposed to i.e. significant improvement in thermal insulation and noise reduction. I had an issue with the order which was immediately resolved. Would thoroughly recommend."

Duncan

via Trustpilot

"Experts in their field, a well run family business. Pleasure to deal with. Good communicators and they produce a quality product."

James Sunderland

via Trustpilot

Frequently Asked Questions

Find professional answers about krypton double glazing specifications, and determining when krypton is the best option for your project.