Close roads to let kids out to play CITY streets should be closed to cars in afternoons so children can play and rooftops should be turned into safe play spaces, a world leading health and planning expert says. The proposal by Dr Karen Lee targets a severe shortage of places for children as schools go high rise, crowded classrooms don't have enough space for jump rope competitions and residents fight playground plans. Dr Lee is New York City's award-winning healthy urban planning expert, who has helped reverse childhood obesity rates in the city and will address NSW government planners today. She said Sydney's severe play space shortage could be easily dealt with by opening city roofs and streets to fun. Space-strapped cities such as Sydney, with neighbourhoods that were "fully built," could host "play streets" for children to skate, ride bikes and scooters without car danger, she said. "If there is space to build playgrounds and parks then we should do so but we have neighbourhoods, already fully built, and we may not have enough play space for the kids," she said. Dr Lee said it had worked successfully in NYC, where single blocks were closed to cars at certain times. "It can occur weekly or every day at certain times and it is opened up for children to play," she said. Dr Lee said soccer lessons could be held and neighbours meet to get to know one another. There was strong evidence that having space for active play increased physical activity in children and adults. Schools have told the National Health Foundation they don't have enough room to hold Jump Rope for Heart activities and plans are being considered to put primary schools in high-rise buildings. Dr Lee said Sydney could also look to its rooftops for space. "As more green roofs are created, what if we also made that space for places for play?" she said. New play areas should also include facilities for adults as well as children, she said. Heart Foundation CEO Tony Thirlwell said so much of Dr Lee's experience could be directly applied in Sydney and beyond. "City planning and design is a major detriment of public health, with the ability to boost physical activity levels and mental health as well as improve Australia's obesity trend and the incidence of chronic illness such as heart disease, diabetes and some cancers," he said.