by ericmark »
Sat Oct 30, 2010 6:20 pm
If the property is wired to BS7671:2008 then no. However if wired to comply with earlier regulations then earthing may be required.
Under the 2008 regulations all electrical items in a bathroom need protecting with a RCD of 30ma and 40ms even the lights and as a result earthing requirements have been relaxed.
I don't have early regulations to hand but general idea is all metal items which could import a potential i.e. radiators unless supplied with plastic pipe. Water pipes unless again only metal bits are in room and under floor etc is plastic. Waste pipes if metal. Are all connected together. They do not need to be connected back to the incoming earth although in practice since the lights will be earthed it will be. Idea is everything is same voltage what ever that voltage is does not have to be zero voltage.
Each version of BS7671 has brought in some changes so unless one knows which version has been used hard to say exactly what is required.