Lower U-values from the cavity
Argon and krypton gas filling
Replacing the air in a sealed unit's cavity with a denser gas slows heat transfer. We fill with argon for standard cavities and krypton for the narrow ones.
- Argon for 16–20 mm cavities
- Krypton for 4–8 mm cavities
- Fill checked on every unit
Argon
Argon is around twice the density of air and is the most common fill in new units today. It works in most cavities, and is at its best between 16 and 20 mm.
Krypton
Krypton is much denser than argon and excels in narrow cavities, particularly 4, 6 and 8 mm. We do not recommend it for larger gaps, because it gives no improvement over argon at 16 or 20 mm.
It is the usual choice in our heritage range to get the lowest U-value from a slim unit. The performance comes at a higher cost, so talk to us about whether it is worth it for your job.
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