Firefighters were called to Think 3E in Links Road, Wellingborough, just after 9am today (Thursday).
Two crews from Wellingborough and Irthlingborough went out initially but on arrival the first crew found the building to be heavily smoke-logged and requested the assistance of a further two pumps, which came from Rushden and Burton Latimer.
The fire involved a lorry inside the premises.
Crews managed to bring the fire under control by 11am and firefighters then vented the property using ventilation fans.
The lorry was severely damaged by fire, with light smoke damage to the property.
The cause of the fire is being treated as accidental.