The incident took place around 11.30am on Barnhurst Lane, Wolverhampton.
West Midlands Fire Service attended the scene, where they were called to assist West Midlands Ambulance Service to stabilise the man and bring him down from the roof before he was taken to hospital.
A statement from West Midlands Fire Service said: "At 11:35am on Thursday 19 May we were called to assist Ambulance colleagues on Barnhurst Lane, Wolverhampton, where a man had been taken ill whilst on the roof of a two-storey house.
"An aerial hydraulic platform, ladders and specialist working at height equipment were utilised to stabilise the casualty and safely bring them down from the roof. They were then taken to hospital."
A spokesman from West Midlands Ambulance Service said: "We were called to reports of a patient who had become unwell on the roof of a property on Barnhurst Lane at 11.30am. Two ambulances, two paramedic officers and the Trust’s Hazardous Area Response Team attended the scene.
"On arrival we discovered a male patient who was brought to safety with assistance from fire service colleagues and treated on scene before being taken to New Cross Hospital."