I've got an outbuilding attached to the rear of my garage. The outbuilding has floorboards, and is roughly 8 feet square. It may be two bricks thick (hopefully with a cavity) and is internally plastered.
I can see no ventilation in this room except two windows (which are usually shut, but do open), though I can certainly see damp.
Is it acceptable to fit a two air brick vents (maybe one near ground level above DPC, and one around the ceiling height), or should I install a sub-floor vent (which would probably be more expensive)?
The garage has a concrete floor and two air bricks in the position described above.
As this is an outbuilding, I don't want to go over the top.