Damp in garden building floor...

[davek0974]

I have a 10 x 8 wood extension to a garage in the garden, have just removed a couple of boxes that were on the floor and found dusty white mould - mildew???

The floor is 22mm marine grade ply resting on 2x3" treated battens on a concrete apron - have seen that this area gets water puddling in heavy rain.

The front and back walls are resting on battens so there is no air flow there, have just been looking and it seems the end is also pretty well sealed to the floor by the cladding.

Am i right that I need to get some air in there???

I was thinking of 1st drilling some 1" holes through the lower cladding strip maybe that will help?

If not, pull the lower strip right off maybe, exposing the ends of the support battens and the voids between???

Its not serious yet but is only two years old so want to halt decay as much as possible. :)