Standard for systemised building envelopes (replaces all three earlier Standards) 2006


For CWCT Member discounts on Documents and Events, please sign in to the Cladding Forum

More info

CWCT Member Price: £125

This document cannot be downloaded. Once ordered we will send a copy to you.

Standard for systemised building envelopes 




The CWCT Standard for systemised building envelopes was published on 1 March 2006. It is a registered document - each copy is numbered - and purchasers are automatically sent Technical updates by email as they are published.

The Standard covers all forms of systemised envelope construction and their integration into a complex envelope. It replaces the existing Standards for curtain walling, ventiliated rainscreens and slope glazing.

The new Standard is expanded to include:

  • Better specification of thermal and acoustic performance
  • Access and maintenance requirements
  • Interfaces
  • Brise soleil and other ancillary elements

There are also many changes from the old standards to incorporate amendments to the Building Regulations, the introduction of British European Standards and changes to British Standards.


The Standard is published in nine parts, together with a Standard for testing building envelopes, as follows:

  • Part 1 - Scope, terminology, testing and classification
  • Part 2 - Loads, fixings and movement
  • Part 3 - Air, water and wind resistance
  • Part 4 - Operable components, additional elements and means of access
  • Part 5 - Thermal, moisture and acoustic performance
  • Part 6 - Fire performance
  • Part 7 - Robustness, durability, tolerances and workmanship
  • Part 8 - Testing
  • Part 0 - Specifiers' checklist and certification
  • The Standard acts as a comprehensive guide to all aspect of performance that have be included in an envelope specification. It is part of the National Building Specification (NBS) and the basis for the envelope standards of the National House Building Council (NHBC). It helps Specifiers to:

    • Choose classes of performance appropriate to the UK climate when using European test methods
    • Comply with UK Building Regulations
    • Ensure appropriate communication between different designers and contractors
    • Set appropriate standards for finish and appearance.