A fire started in a garage in Heanor in the early hours of Monday morning.
Fire crews from Heanor, Ripley and Ilkeston were called to the blaze on Burns Street at 2am.
Four firefighters in breathing apparatus began fighting the fire, which had spread to a car, and were joined by two others.
The two occupants of an adjacent bungalow were taken to the QMC in Nottingham as a precaution for smoke inhalation.
An investigation revealed the fire started from an electrical fault in a fridge.