Around 8 million people a year are expected to be sheltering under Kalwall at the beautifully-designed new bus station at West Croydon. Designed by Transport for London Architects, this is an unusual example of how translucent Kalwall can offer many different advantages above its normal use for translucent cladding and rooflighting.
The brief for this project was to create a user-friendly waiting and assembly shelter to service the thousands of passengers using this important and busy transport hub linking the 150 buses an hour with the adjacent tram stop and West Croydon railway station providing routes to Canada Water and east London, and via the tram network to Beckenham and Wimbledon.
The normal choice of construction for a weatherproof and translucent cladding canopy would be to glaze the roof with glass, However in-house architect Martin Eriksson and the project team at TfL realised that Kalwall offered a better solution in this location which would not only solve the brief and contribute to a better design but would offer many other benefits over traditional glazing.
For example, since Kalwall is much lighter than glass it meant that the supporting structure needed to be less strong and far less chunky. In additional, not only would the shelter be less high but the vertical supports would be less obstructive and open up a better view of the environment including the very attractive church nearby which had previously been blocked from the view of waiting passengers.
Unlike conventional glazing, highly insulating Kalwall is far more attractive than glass while eliminating shadows and glare and the stark contrasts of light and shade; improving the experience for passengers below.
Also, due to the way it diffuses natural daylight downwards and at night reduces vertical illumination and reflection upwards, it controls light pollution on the surrounding high rise buildings. Soil and detritus are less obvious on Kalwall than on glass and maintenance and cleaning is much simpler because access scaffolding is not required and maintenance staff can safely walk across its surface.
One of the main attractions of specifying high performance Kalwall for conventional buildings is its unique effect on both the interior and exterior. Internally, rooms are flooded with diffused natural daylight which creates a stimulating and very attractive environment. Although translucent, it also offers the big advantage of privacy while the elevations appear crisp, simple and inviting. When illuminated at night they emit a very attractive ethereal glow.
Apart from being specified for all types of new build, Kalwall is increasingly used for the refurbishment of cladding or rooflights on aged buildings.