Generally speaking, I thought the 'proper' basement subfloor method was: Vapour barrier, 2x sleepers (optional rigid insulation between), plywood/OSB
However, I read an article recently that implies that the vapour barrier will trap moisture between concrete and create a potential moisture problem (even in apparently 'dry' basements). Instead, the recommended method was to apply rigid polystyrene directly to the floor with no vapour barrier, followed by sleepers/plywood. Supposedly, the polystyrene allows moisture to pass through and reduces the chance of mold/rot.
Has anyone else heard of this practice? I actually found more than one article about it...and the use of a vapour barrier appears to be a big problem.
FWIW, I want to install an insulated subfloor suitable for hardwood installation (with minimum height).