Thanks for the reply; this is a purpose-built shed with half the floor slatted to allow ventilation. There is also an air vent incorporated into the side at the top. I would like to know of any effective treatment for getting rid of this mold (which was introduced from a rather damp load of firewood logs by a local supplier whom I will never contact again)?
Any suggestions in overcoming this problem would be much appreciated.
If the mould is just present on the surface of the shed walls and roof (rather than the shed rotting) I would suggest removing as much fire wood as possible, washing the surfaces with a strong bleach solution, allow to dry and then put the firewood back.
If you had mould in your bathroom due to excess moisture you would probably clean it with bleach, so why not treat your wood shed the same way?
A lot of folk make the mistake of stacking the wood like they're building a dy-ke and leave not much for the air to get through, then they leave no space between the rows and make things even worse. I've seen the white mould on some of our logs that sat rather too long in the rain.
That's why my woodsheds are made from pallets....cost next to nothing.