The government has recently launched a consultation on proposed changes to Approved Document B. The scope of the consultation includes several areas that directly affect the facade, including various small but important clarifications and technical changes to the guidance within Approved Document B, and updated guidance on external wall systems and balconies and a review of the scope of the ban on combustible materials in and on external walls.
Full details of the consultation can be found here.
Amended versions of ADB Volume 1 and ADB Volume 2 can be found via the same link, together with a link to provide feedback.
CWCT will be providing feedback on the facade specific on behalf of our Members, and in order to do this, we need your feedback.
To facilitate this, we have produced a short survey – please click here for details.
It is really important that we respond to this, so please provide your feedback by 1 June 2026.
A very brief summary of the façade specific changes can be found here.
David Metcalfe - April 01, 2026
Thanks for the comment.
This needs further investigation and potentially doesn’t offer a blanket exemption for laminated glass used in spandrels (or as balcony balustrades).
Section 6 of the consultation questions provides further context, and says the following:
‘Laminated glass products are defined (in regulation 2(6)(X)) as any panel or sheet, having a total thickness of more than 17.5mm but no more than 26mm which is composed of two or more layers of glass, and one or more layers of interlayer material which is a substantial layer made of a material having a gross calorific value of no more than 41MJ/kg when tested in accordance with BS EN ISO 1716 and a thickness less than 1.6mm. A substantial layer is defined as a layer which is at least 1mm thick or has a mass per unit area of at least 1kg/m².’
It is presumed that the limits placed on the thickness of the glass relate to the testing that was carried out as part of the government research on balcony performance.
Sean Trowell - April 01, 2026
Good morning,
Thanks for sharing the summary on the proposed texts,
One item in the proposed text that doesn’t seem to be in the CWCT summary is the indication that spandrel glass is now included as an exemption from the Regulation 7(2) requirements for doors and windows (and possibly by extension curtain walls?) – see Section 10, 10.6, 3f:
“3. The following non-extensive components are exempt
…
f. Doors, door fames, window frames, and any glass used in both window panes and spandrel panels (including laminated glass as defined in the regulation 2(6)(X)).”
Further to this, whilst the position of CWCT and ASFP is clear, there still is still no prescribed testing standard for curtain wall firestopping (linear joint sealing) in Approved Document B.
Regards,
Sean