Two appliances from Danes Castle and Middlemoor together with an aerial platform were mobilised.
When they got to the scene they had to force their way into the building wearing breathing apparatus.
The fire was so bad that two more appliances were mobilised from Danes Castle and Topsham, together with support appliances from Exmouth.
But within half an hour two further fire crews were needed from Topsham and Credition.
The annex was gutted by the blaze but the crews managed to stop the fire from spreading to other buildings.
Commander Gerald Taylor has been talking to our reporter Wendy Buckingham about the fire CLICK HERE
Surf Life-Saving GB is now appealing for office space for its team of ten. The charity reckons the building won't be rebuilt for at least 12 months. It would appreciate any other help which can be given to help it get back on its feet.