The appearance, quality and performance of a building envelope are totally
dependent on good construction. The use of qualified installers and
trained supervisors is the single most effective way to achieve a good
The building envelope may be installed by specialist contractor direct
labour or by a labour only subcontractor. In both cases it is recommended
that installers are trained by the company that designed the system and
supplied the materials. CWCT has implemented a system of installer
training leading to a CWCT ‘Installers card’.
It is equally important that architects, engineers, main contractors
and others with a supervisory role on site are trained and capable of inspecting
the work, again CWCT have implemented suitable training programmes.
As a check on workmanship site testing may be undertaken during installation
and on completion. This may include:
Whole building air leakage testing
Hose testing for watertightness