That study carried out particle transport measurements for full-scale timber frame structure similar to a wooden floor. The penetration is highly dependent on pressure difference and not on holes in the surface boards of the structure. The results showed that surface contacts of mineral wool with other building elements may have an important role in penetration.
Fungal spore transport through a building structure
Indoor Air, April 2004, Vol 14, n° 2, pp 92-104, 10 Fig., 5 Tab., 46 Ref.