The bodies of John Averis, 27, Ashley Stephens, 20 and Darren Yates-Badley, 24, were recovered from the building in Atherstone-on-Stour in November 2007.
Defending, Ben Compton QC said the Atherstone fire marked the "darkest year" for firefighters in the last thirty years and had left families and colleagues filled with "grief and emptiness".
' Most of the school (Barr's Hill) had been evacuated to Leamington at the beginning of the war and later to Atherstone but I, an only child, had not wanted to leave my parents.