I've got a new house so I imagine I will be using STW a lot for DIY questions over the next year. Is there any alternative more specific DIY site. I need a parktools style site for my house!

The previous owners had big chandaliers in 3 rooms but have taken them down. 1 of the rooms has a proper mount but I cant work out what they've used to take the weight in the lounge and dining room.

There's a plaster ceiling rose, a very messy small hole and then I think lath and plaster. There's no sign of what they have screwed into. I don't want to destroy the rose but I don't want to the light to rip down the ceiling either? Suggestions?

drive a screw in and hang a turnip from it

how heavy is the light?

Maybe some sort of strap between the joists?
As for diy sites, try diynot.com or ultimate handyman. Screwfix is very good too but full of self riteous to$$ers. Way worse than here at it's worst even!

The light isn't bought yet, but it's a big room with a 14ft ceiling so it will be reasonably heavy.

Turnip, eh? I was expecting only fools and horses comments.

well, if i was putting up that light, and wasnt happy that there was already a large bith of wood above the cieling to screw into, i would put one ther. So bascically measure out where the light is, go to the room above and lift a floorboard. Get a piece of wood with guite a large surface are, and put it above the light. You might want to drill a hole in the wood for the cables to go through. Then screw straight into this wood. Saying that, if the light is REALLY big (i'd say more than4 or 5 kilos), you might want to knock something a bit better up, that can be screwed into the joists above the cieling.

I hope that makes dense