Specialist heritage glazing & slim sealed units
6mm Krypton Cavity•14mm Nominal

4mm Low-E Float / 6mm Krypton cavity / 4mm Activ Float

Request made-to-measure heritage double glazing combining 4mm Low-E Float on the inside, a 6mm Krypton gas cavity and 4mm Activ Float as Panel 2. This separate 14mm nominal sealed-unit make-up is available to discuss with a specialist supplier.

Interactive Cross-Section

Exploded Sealed Unit Architecture

Inside Pane4mm Low-E (Annealed)
Cavity & Gas6mm Krypton
Outside Pane4mm Activ Float (Annealed)
Nominal Depth14mm (±1mm)
Sightline Flange: 7mm
Spacer Finish: Warm-Edge (Black)
Secondary Seal: Polymer Heritage Butyl
Sightline is perimeter seal depth into rebate. Cavity is noble gas gap. Gas does not recolour glass.

Activ float glass in a heritage sealed unit

This 4mm Activ float second-pane option lets you request an Activ glass make-up alongside an inside Low-E pane for a heritage window project. Ask your supplier to identify the exact Activ product, coating orientation, cleaning guidance and compatibility with the proposed sealed unit.

For this 4mm Activ Float product, the selected 6mm cavity and Krypton gas give an indicative U-value baseline of 1.5 W/m²K. Panel 1 is 4mm Low-E Float; Panel 2 is 4mm Activ Float. The total nominal unit thickness is 14mm. Confirm your rebate depth, sightline, spacer colour and the declared thermal performance with the supplier before ordering.

Choosing 4mm Activ Float for heritage double glazing does not establish planning or conservation permission. Your supplier should confirm the exact product, and any required appearance match or project approval must be checked separately.

Technical Specification

Inside Pane:4mm Low-E Float
Cavity & Gas:6mm with Krypton
Outside Pane:4mm Activ Float
Nominal Thickness:14mm (±1mm)
Indicative U-Value:1.5 W/m²K — indicative baseline; confirm with supplier