When they arrived after the 9.20am call the crew from Telford found a mattress ablaze inside the four metre by three metre brick building.
They were able to put out the fire before 10am.
No-one was inside the building.
A fire crew from Cleobury Mortimer were called out to an embankment fire on the Severn Valley Railway at Highley near Bridgnorth at 11.30am. Firefighters used beaters and knapsacks to extinguish the flames by 12.14pm.