While the WA Electrical Requirements (WAER) are quite clear on the mechanical protection required for consumer mains in cavity walls of both double brick and brick veneer, there is not the same clarity for walls without a cavity.
The requirement for mechanical protection of consumer mains not protected by a service protective device installed within a stud wall will be achieved by installing the unprotected double insulated consumer mains in heavy duty conduit enclosed in galvanised steel pipe or a galvanised box section, where the consumer mains are installed less than 50mm from the surface. Where unprotected consumers mains are installed more than 50mm from the surface, heavy duty conduit is required and no additional mechanical protection is required.
Where there are double brick walls with no cavity in place and the consumer mains are installed on the surface or within 50mm of the surface, the protection will be by heavy duty conduit enclosed in galvanised steel pipe or suitable galvanised steel cover. Where consumers mains are installed more than 50mm from the surface in heavy duty conduit, no additional mechanical protection is required.
Above: Mechanical protection of consumer mains