Insulating a ground floor flat

[matt26]

Hi all

I am renovating a ground floor flat (1990s), which for most of the time does not have any occupants above. I've read that it's common not to insulate between flats because people generally keep the heating at similar levels and the temperature difference means it's not worth it, but for us it's usually a cold empty flat above. Our ceilings have around 100mm void above the plasterboard, and a concrete floor above that. Does anyone have any advice on what to do with insulation here? The flats are electric only heating, so bills are quite high. Is it worth ripping down the plasterboard and filling the void with insulation? Any particular types? Any problems with ventilation if we do?
Thanks for any input!

[Bitpipe]

Welcome.

 

I remember when we lived in a second from end terrace our front room was always cold as the neighbours used their front room as an art studio in the daytime only and spent evenings in the kitchen / diner which had a woodturner and was always cosy. 

 

How is the flat ventilated at present - i.e. trickle vents in windows, externally vented extractor fans in bathroom / kitchen etc?

 

Unless your ventilation system is dependent on that void then I can't see the issue in ventilating it. 

 

Are there services in the void (fouls, water, power)? Do you have recessed lighting (spots)?

 

How is the void created  / ceiling suspended?

 

You could use rigid insulation such as XPS which will give good results for that thickness but may be tricky to fit around obstacles - you could strip back the entire ceiling and bond the insulation to the concrete ceiling with foam. Or you could use rockwool which maybe easier to fit around existing structures and services. 

[tonyshouse]

Problems could occur if you insulate as then their concrete floor would be even colder and potentially attract condensation on the undersidevabove your insulation. 
 

if it was mine I would insulate 

[Mr Punter]

Without wishing to give you more work, is your floor insulated?  If it is just solid concrete you could add some insulation to both the floor and ceiling.  50mm Celotex on both would make a huge difference.