Damp Proofing

White mould on floorboards under lounge carpet

Anonymous user 28/02/2024 - 3.53 PM

On lifting our ground floor lounge’s carpet, we found white mould on the plywood underneath and it was very damp. It took 48 hours to dehumidify 20 litres from the room. We cleaned off the mould with bleach, vinegar, etc, but on lifting one ply wood board to investigate the underside, the mould is on the bottom side too. These sit on top of our floorboards, which are on a floating frame over soil (1910 house). We’ve cleared the air bricks (2 at the front and 2 at the back) and there’s is no leaking pipe. What do you think could be causing this? Should we be replacing the ply or is drying it out going to be enough to fit carpet over it once the damp has gone?