In the UK, building regulations governing energy efficiency of windows are part of Part L of the Building Regulations. For new windows, the maximum Uw value is typically around 1.2 W/m²·K, and replacement windows generally must achieve around 1.4 W/m²·K with a minimum Window Energy Rating of B. These values aim to reduce heat loss and ensure energy conservation. In some guidance, even stricter target values for new builds may apply based on design and performance targets.

Because Aura Balance 68 uses a 24 mm single-chamber insulating glass unit and a basic profile, it is unlikely to achieve Uw values below UK regulatory limits for new or replacement windows required for heated residential spaces. It is instead suited for applications where high thermal performance is not a key requirement.

The Uw value describes the overall thermal transmittance of the entire window (frame, glazing, and spacers).
The lower the Uw value, the better the thermal insulation and the lower the heat loss through the window.

Aura Balance 68 is not intended for use in heated living spaces where compliance with WT 2021 is required.
It is designed primarily for unheated or cold rooms, where thermal insulation requirements are less restrictive.