I inherited a large (4m x3m) wooden shed with a suspended floor. It's built on two rows of concrete blocks with a DPC on top. The wooden shed frames are mounted the DPC. Flooring joists rest on the DPC above the blocks and the wooden floor is fixed to the joists. When it was constructed, no ventilation was provided underneath, loads of wood off-cuts and debris were left there and extensive dry rot started appearing up the walls. I've now removed the floor and the joists - it was quite a fungal foray! However, some of the framing timbers are also badly affected. Rather than carry out repairs, I've decided to dismantle the wooden shed and build one using concrete blocks with a solid floor. Are there any particular precautions that I'd need to take when building in this area? Is it safe to reuse any of the original concrete blocks that were part of the foundation as hardcore etc.?