I have a plywood subfloor in a ground floor extension that is laid directly on the joists. The current floor is half solid wood tongue-and-groove laid on top of green fibre underlay and half fake tile-effect fibrous T&G on the underlay on chipboard. The floor and subfloor is coming up so I can install strutting to stiffen the floor as it is a bit bouncy and I want to tile the non-wood bit.
While I have the subfloor up, it seems like a good opportunity to lay some insulation to keep the kitchen floor from getting too cold in winter - I was going to just lay some glassfibre matting between the joists after strutting. Is that appropriate?
The floor is also quite boomy (plywood over a big sounding box, basically). Is there anything I can do about that, other than the glassfibre insulation?