THE boss of the Buildings Department is examining the case of two cooling towers erected on the roof of Tak Yan House in Tsuen Wan, where department staff demolished the homes of illegal roof-dwellers. The Old District Rooftop Residents' Concern Group petitioned Helen Yu Lai Ching-ping's department yesterday, as the department issued a statement agreeing to seek more information. 'When all necessary information is available, I will be able to decide what to do and I will tell all concerned,' Mrs Yu said. 'We do not need petitions to prompt us into action. However, we do welcome reports from the public. They are a good source of information to help stop new illegal structures. 'Where there is a case and we are ready, we will take action. The illegal structures re-erected on Cheuk Ming House in the same area are a case in point.' But Mrs Yu failed to appear at a protest in Central when top-floor residents of Cheuk Ming and Tak Yan houses rallied against what they claimed were the department's double standards. Tak Yan residents said the department had removed homes of rooftop-dwellers, yet had taken no action to remove the water-coolers which now stood on the roof. Cheuk Ming House residents said departmental demolition of roof-top homes had damaged the concrete, leaving top-floor flats with leaky ceilings. When residents put up structures to stop water leaking, they promptly received a letter from the Buildings Department advising them the work was unauthorised, they claimed. Building Authority Senior Structural Engineer Robert Garton said an investigation into both buildings was still going on and promised a reply after 10 days.