Hi, I am new to this forum. I have a suspended timber floor over a crawl space of 50cm. I have placed 75mm celotex insulation between the joists, then a DPM sheet followed by 18mm osb3 board. On top of this I am planning to have an underlay then r a floating 18mm solid or engineering wood. My question is this. Should I be using vapour barrier or damp proof membrane. I have already added DPM but if this is going to cause a problem then I would rather change it now.
