Hi everyone,
Thank you so much for your replies.
I ended up calling a builder who did some work on the house when we moved in (imagine the conversation we had…he was chuckling away the whole time)
To locate the beams in a victorian house, here is what you do:
you start in the corner of the room where the ceiling meets the wall, and you start counting interval gaps of 400 mm (which is the distance between each beam). You get to the beam where you want to place the pole and you drill a hole to make sure that there is indeed a beam up there. If so, you can full the hole with polyfiller and place your pole there.
I haven’t done it yet because I have never used a drill…I might get the builder to come around.
I will keep you posted as to wether his suggestion worked!