I re-insulating my cold flat roof. I am leaving a 50mm air gap between the decking and the insulation and ventilation as required. But I also need a vapour barrier to go between the plasterboard and the insulation.
I am having trouble finding any vapour barriers? Are they called something other then vapour barriers? Maybe I should be searching for something else? Can anyone recommend one which I will be able to pick up from a local DIY store like B&Q or Gibbs and Dandy etc...
Thanks in advance!