Woodwarm Fireblaze and Firegem. Woodwarm Fireblaze 6ke DEFRA Stove, A powerful highly efficiient stove that can be installed in smoke control areas. This was originally an old open fire,opened up with the recess created and a new slate hearth fitted. Woodwarm brocure photo of the Firegem 5kw, slightly smaller than the Fireblaze.This model with the woodstore underneath. *Both these stoves can sit on a 12mm hearth.