Have been replacing 1930s floorboards and discovered that a partition wall made of breezeblock has been built directly on top of the old boards - probably in the 80s when a lot of bodging was done. This is in an upstairs bedroom. Before now I've successfully tucked the new board under any other walls as they've been safely built off joists but I'm worried there wont be enough of the old board to bear this 'orrible wall's weight. The wall is in the right place so don't want to knock it down if poss.