The owner of the city's largest private garden, the 60-year-old Dragon Garden in Sham Tseng, wants officials to upgrade its heritage status because of what he says are inadequacies in the government's appraisal. Dr Lee Shiu, son of the garden's founder, philanthropist Lee Iu-cheung, made a submission to the Antiquities Advisory Board yesterday pointing out 21 items in the official appraisal of the garden's value that he says need clarification and elaboration. He has asked for the grade-two status of the site to be raised to grade one. The submission, prepared by architectural researchers at Chinese University, is part of Lee's plan to seek matching funds from the government to turn the eight-hectare garden into a conservation project for community use. About HK$30 million will be needed to restore the site on Castle Peak Road. The submission listed alleged inadequacies in the official appraisal, released in March, elaborating on the founder's extensive social contribution and the architectural significance of various parts of the garden. For example, it said, the appraisal failed to describe the many details of the pavilions and other buildings, which draw reference and inspiration from the Summer Palace in Beijing and Chinese calligraphy. It also failed to mention the changing room and the swimming pool, the first structures erected in the garden, which had served as a place for social gatherings for guests, including colonial governors and the local elite. Cynthia Lee Hong-yee, the founder's granddaughter, said: 'One important factor about Dragon Garden that needs highlighting ... is grandfather's pioneering concept of sustainable development in the 1950s.' Recycled granite blocks and glass bottles were used as building materials, and a water catchment collected rain water for irrigation. Lee Shiu invited board members to visit the garden and said he was proud to be requesting an upgrade. 'We note in the news that over 70 private owners have requested their heritage properties be downgraded,' he said. 'We find it such a shame that not many Hong Kong people take pride in their own heritage.' The Antiquities Advisory Board will discuss in the coming months proposals from owners to delist or upgrade historic buildings. Apart from Dragon Garden, there have been calls from owners or members of the public for 96 buildings to be given higher grades. Some 72 owners have requested delisting.