Six fire engines are currently on the scene of the blaze, which was first reported shortly after 10am.
London Fire Brigade reported its firefighters are tackling the fire at a detached house, with part of the first floor and roof alight.
A London Fire Brigade spokesman confirmed: “The Brigade was called at 1007. Fire crews from Twickenham, Feltham and Heston fire stations are at the scene.
“The cause of the fire is not known at this stage.”
One man reportedly escaped the property before the fire brigade arrived and is currently being treated for smoke inhalation.