Part L (2022) Compliance – All Products

Residential Replacement – Glazing Requirements
Overall U-Value of 1.4W/m²K or Energy Rating of B (windows) & C (glazed doors)

Product

Regulation Requirements

OW70

For U-Value compliance a Glass Centre Pane of 1.1W/m²K or better is required

For WER ‘A’ use 28mm Float/Argon/Planitherm Total + with warm edge spacer*
(WER ‘B’ if using OW70 Long Leg on all four sides)

OW80

For U-Value compliance a Glass Centre Pane of 1.2W/m²K or better is required

For WER ‘A’ use 28mm Float/Argon/Planitherm Total + with warm edge spacer*

OB49

For U-Value compliance a Glass Centre Pane of 1.1W/m²K or better is required

For DER ‘B’ use 28mm Float/Argon/Planitherm Total + with warm edge spacer*

OB72

For U-Value compliance a Glass Centre Pane of 1.1W/m²K or better is required

For DER ‘B’ use 28mm Float/Argon/Planitherm Total + with warm edge spacer*

OS29,44,77

For U-Value compliance a Glass Centre Pane of 0.8W/m²K is required

For DER ‘C’ use 28mm Float/Argon/Planitherm Total + with warm edge spacer*

*Alternative Glass Specifications

Guardian Ultra Clear/Argon/Climaguard A

Pilkington Optiwhite/Argon/K Glass S

AGC Clear Vision/Argon/Planibel AS