When were ceiling rose junction boxes invented? They appear to be post WW2 as I have been unable to find any that are older. The ceiling roses I have from the 1920s and 30s are either purely mechanical or have terminals just for live and neutral for the light fitting. Were ceiling rose junction boxes intended as a cost saving feature when constructing houses?
I don't know the answer but I suspect that it is linked to the change in connection practice. I grew up in a house dating from 1890 that in the 60's and 70's still had the original wiring from whenever they fitted electric power (1910?), with independent fuses for each light. When my bedroom light wiring failed, I found it was a spur from the fuse box with single core wires, one via the wall switch, which I replaced with modern wiring. (Don't ask what the original was - possibly ceramic insulation covered in cloth and the conductor might have been iron as it certainly wasn't copper.)
The modern method is to have a loop circuit which takes the power to each light via the ceiling rose with a spur going to the wall switch to provide the switching capability. This arrangement requires additional connections and the ceiling rose is a sensible place to fit them. I therefore think that if you find out when the practice changed you will find when the ceiling roses changed.
I don't know the answer but I suspect that it is linked to the change in connection practice. I grew up in a house dating from 1890 that in the 60's and 70's still had the original wiring from whenever they fitted electric power (1910?), with independent fuses for each light. When my bedroom light wiring failed, I found it was a spur from the fuse box with single core wires, one via the wall switch, which I replaced with modern wiring. (Don't ask what the original was - possibly ceramic insulation covered in cloth and the conductor might have been iron as it certainly wasn't copper.)
The modern method is to have a loop circuit which takes the power to each light via the ceiling rose with a spur going to the wall switch to provide the switching capability. This arrangement requires additional connections and the ceiling rose is a sensible place to fit them. I therefore think that if you find out when the practice changed you will find when the ceiling roses changed.
