We have completely gutted our ensuite, At the moment there are 4 mr16 12v 50w downlights dangling down. These need replacing as, at some point whilst removing ceiling for renovations, some of the lighting fixtures were taken off and have been lost in the rubble.
I would like to replace these lights with 4 mains 240v downlights as I believe there are more LED variety with mains GU10 lights as opposed to low voltage mr16.
My question is would is be a simply swap. i.e taking lighting fixture and transformer off and replace with mains voltage lighting fixture or do I need to replace the existing wiring as well? I ask this as the existing wiring consists of thin white wires and I thought it would have been the standard grey thicker lighting wire.
You will need to install IPX4 rated light fittings or better. It is prefereable to use a SELV transformer to feed the lights if in an area that it likely to be splashed by water or above where you're showering.
The fire rating is to stop fire going through the holes you cut and not to spot fire created by the light. So it's not an electrical requirement but depends on the building.
230vac is classed as low voltage 12 volt is extra low voltage. Unlikely you need IP65 the zone dictates the IP rating.
701.512.2 External influences Installed electrical equipment shall have at least the following degrees of protection: (i) In zone 0: IPX7 (ii) In zones 1 and 2: IPX4.
So likely IP54 is good enough but should say on packaging suitable for bathroom since lights are now required to be RCD protected you may need to all this as not replacing like for like. However with RCD protection should water get in the lamp it should fail safe.
If you are going through a building inspector best is always to list what you intend to do. Better that he says no before rather than after but the inspectors with my mothers bathroom did not look at the job they took my installation certificate and just issued the completion certificate.
Most areas of UK bathroom work is still notifiable but in England it depends I think on the zones now but I live in Wales so no change for me. You will need to check yourself.
The problem with most DIY is to fill in the installation certificate you need to enter the readings from the test meters and the meters are expensive as are the LABC fees so if you want to be legal then likely cheaper not to DIY.