Lighting under bathroom

[PhilipFrampton]

Having had experience of this...

Are IP65 downlights IP65 rated only from the exposed front or the entire unit? My utility room ceiling is underneath a bathroom, the external wiring aside, would an IP65 rated light have continued to function while slightly wet or would water easily ingress from the back?

On a different point, why do downlighters need to be fire-rated but pendants not when a pendant quite often has an inch-sized whole behind it for cables?

 

[flameport]

They are rated from the front only - only from water ingress from the room which they are illuminating. Any water from above will enter easily and destroy them, just as with most other light fittings.

Downlighters do not need to be fire rated in the majority of situations.
For those where fire rating is required, a standard pendant would not be acceptable either.

 

[PhilipFrampton]

Downlighters do not need to be fire rated in the majority of situations.
For those where fire rating is required, a standard pendant would not be acceptable either.

I've never actually read the part B regs. I thought that in a normal domestic 2 story house you need F rated on the ground floor to slow the rate of spread of fire, but in most houses I know the pendants may have started as a single cable burried in plaster but they end up a gaping whole eventually.

 

[JohnW2]

I've never actually read the part B regs. I thought that in a normal domestic 2 story house you need F rated on the ground floor to slow the rate of spread of fire ...

There wouldn't be much of a point really, given that such houses have massive connection between floors (aka a staircase) and no requirement for fire doors. AFAIAA, it's only really when one gets to flats, or some houses >2 stories, that such things come into play.

Kind Regards, John

 

[ban-all-sheds]

My utility room ceiling is underneath a bathroom, the external wiring aside, would an IP65 rated light have continued to function while slightly wet or would water easily ingress from the back?

Don't worry - the lights will get automatically disconnected when the ceiling is brought down by the water.