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?
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 asked a building electrician some time ago who verbally informed me that the commonest arrangement of wiring ceiling lights in new build houses in the 1930s was a circuit which took the power from the consumer unit to each ceiling light in turn although radial wiring of lights was also used. The cables terminated in junction boxes inside the ceiling cavity with a cable to the switch and another cable to the light fitting. It requires a separate junction box and ceiling rose for each light fitting. This arrangement is still used today and is increasingly found in new builds because it is easier to change light fittings than if ceiling rose junction boxes are used as there is only one cable to the light fitting accessible from the room rather than three. Ceiling rose junction boxes became common in new installations around the time that lath and plaster ceilings were replaced with plasterboard.
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 asked a building electrician some time ago who verbally informed me that the commonest arrangement of wiring ceiling lights in new build houses in the 1930s was a circuit which took the power from the consumer unit to each ceiling light in turn although radial wiring of lights was also used. The cables terminated in junction boxes inside the ceiling cavity with a cable to the switch and another cable to the light fitting. It requires a separate junction box and ceiling rose for each light fitting. This arrangement is still used today and is increasingly found in new builds because it is easier to change light fittings than if ceiling rose junction boxes are used as there is only one cable to the light fitting accessible from the room rather than three. Ceiling rose junction boxes became common in new installations around the time that lath and plaster ceilings were replaced with plasterboard.
