metal ceiling light

[woodmere]

how do i fit metal light fitting when there is no earth connection at rose

[buildersmate]

You can't and you mustn't. A conventional lighting ring would bring the earth terminal from the twin and earth cable that feeds it to a blank earth point on the rose. That's been the convention for several decades in the UK. Either its very old or its been fiddled with. Have you got a conventionally wired lighting circuit? There should be three cables (or more) terminated at the rose - two of them will be the ends of the ring feeder from the lighting fuse/breaker in the consumer unit, the other will be the twin/earth cable running down to the switch for this light. These three cables should have earth wires - unscreened copper - that should be twisted.

[stanleyman]

Buildersmate is right, you shouldn't fit a metal fitting without an earth. However, check that the earth wires have not been connected behind the rose in the ceiling space, often done if a fitting was there previously.

You should have twin and earth lighting cable and if yours is only twin cable you should consider a rewire. You can run a separate 1 mm earth cable to a nearby earth point to get over the problem in the short term.