CWCT.

The Centre for Window and Cladding Technology (CWCT) is the UK industry body responsible for standards, training and testing for facade engineering. CWCT is based at the University of Bath and publishes the Standard for Systemised Building Envelopes — the de facto UK test regime for curtain walling and rainscreen cladding.

On a typical UK facade package, CWCT testing applies at two levels: system test data provided by the system house (Schüco, Reynaers, Kawneer etc.) demonstrating the product family has passed the relevant performance tests, and project-specific Performance Mock-Up (PMU) testing on schemes above roughly 5,000 m² of facade.

A standard PMU sequence covers air permeability (EN 12153), watertightness (static EN 12155 and dynamic CWCT TN75), wind resistance (EN 12179) and impact (CWCT TN76).