Thursday, 19 March 2009
One of our readers had the following question regarding firewall regulations:
"Our current double garage opens directly into the kitchen and has a common wall with the lounge as well. The existing walls are the required 230mm up to the underside of the roof tiles. I now would like to convert the one side of the garage in to a work/sewing/hobbyroom. Can the new dividing wall be made of a drywall material or do all firewalls need to be made of bricks or cement blocks?"
Les responded as follows:
Thank you for your enquiry. There is no difficulty with using dry walling as a fire barrier between your garage and the proposed hobby room. There are a number of drywall systems that are on offer and any of them that provide a half hour fire rating will be suitable.
This is effectively one layer of 12,5mm Rhinoboard on each side of the panel wall which must be built from floor to the underside of the roof sheets or tiles. A double layer of 12,5mm Rhinoboard will give a 1 hour fire barrier and make the wall reasonably sound proof. The single layer wall (half hour fire rated) is not particularly sound proof and you may require that additional insulating materials be included in the wall cavity to improve sound proofing.