Hoogovens' kal-zipregistered has been specified for the unusual sliding roof of the £121 million Cardiff Millennium Stadium, the new home of Welsh rugby. The £2.8 million contract has been won by Kelsey Roofing Industries, a leading team-kal member. David Elder, of The Lobb Partnership, said the system had been chosen because of the company's experience on two previous large projects involving unusual geometry - Wimbledon No. 1 Court, by bdp; and the Scottish Exhibition and Conference Centre, by Sir Norman Foster. Perforated natural aluminium has been chosen for the structural decking to meet acoustic requirements, and to cope with the marine environment. The final finish will be 0.9mm gauge kal-zipregistered natural aluminium transported to site in 30m lengths and welded in-situ to the required 60m lengths.