Air ambulance paramedics were called to a Berrylands street after a man fell from height.
London's air ambulance landed at Christ Church Primary School after reports the man had fallen in Pine Gardens shortly after 1pm.
Kingston police said the man was taken to a south London hospital in life-threatening condition.
His family have been told, a spokesman said.
Health and safety investigators have arrived in Pine Gardens, where scaffolding surrounds a detached house.
A Health and Safety Executive spokeswoman said: "We are aware and making further enquiries."
- Do you know more? Call the newsdesk on 020 8722 6317 or email jon.sharman@london.newsquest.co.uk
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