Form plywood as a subfloor panel

[laufera]

Building a vacation home on a pillar foundation and planning to use formplywood (found a lot of boards in the old house when I bought the property) as the subfloor board.

There are no disadvantages to that, right?

 

[Helioz]

The boards should work; however, they are not mold-resistant like underfloor plywood, so mold growth can still occur. They are also diffusion-tight, which regular boards are not.
http://www.beijerbygg.se/store/priv...-9x550x1200-vis-0-66m2-900211619#.U_RzOGPZNOI

 

[laufera]

Since formplywood does not get wet and only the surface can, the risk of mold growth should be minimal. Or?

 

[Helioz]

Since formplywood does not get wet, only the surface can get wet, the risk of mold growth should be minimal. Or?

Mold growth occurs through condensation and heat, it will clearly condense water on the surface where growth can occur. Whether it affects the plywood/crawl space is another question. It's really such a small amount of money to save, so rather use boards intended for ground-level use.
http://www.byggmax.se/skivmaterial/byggskivor/plywood-och-osb/trossbottenskiva-p07040
http://www.beijerbygg.se/store/priv...550x1220-0-67m2-massiv-900207500#.U_R7X2PZNOI