Should have left the air vents open, "simples."I have important information to contribute here! I insulated the full depth of my floor joists and got dry rot. Had to take it all out, replace parts of the joists.. big work. The wood needs exposed surface area to breathe so you should only ever insulate two-thirds of the depth. If you have 150mm joists you should only have 100mm insulation.
(I have absolutely no idea why I took that Johnnyraz post so personally)