I have a substantial original Victorian plaster ceiling rose. There is a hole at the centre about 20mm across for the main lighting supply wire. There is evidence of previous fittings being fixed direct to the plaster. I wish to fix a chandelier weighing about 15kg. The obvious thing to do is to lift the board above and fix solidly to the floor, but someone helpfully installed an Amtico floor to the bedroom above so this is a huge task.
There is a void of about 35mm between the back of the center section of the rose and the ceiling.
Any ideas gratefully received.