Crews from Ryde and Shanklin were called to the address on Collingwood Road at 15:02 following reports that a tumble dryer had caught fire.
Two main jets and a hose reel are being used to tackle the blaze, which has severely damaged the detached building.
UPDATE @ 16:05 – The fire has been extinguished and contained to the garage.
Firefighters have used a thermal imaging camera to check for hot spots and are damping down the area.
UPDATE @ 16:42 – One appliance from Shanklin remains on the scene.