Crews suspect a fire in a portable building last night (Sunday) was arson.
The incident happened just off Roselee Close, Siddal, at 10.55pm.
Crews from Halifax and Elland attended and used two hose reels and two breathing apparatus to extinguish the flames.
The building was completely destroyed.
Nobody was injured.
Crews left just after midnight.
A West Yorkshire Fire Service spokesperson said they suspected ignition was deliberate.