I spoke to Fballs today and they are claiming there new liquid dpm, can go over floors which have no physical dpm ?? I need to come up with a solution/cost for an estate I work for, where we have one or two probably a year where vinyls have bubbled from moisture, there all old cottages.
I've now used F.ball F78 a few times and it takes longer then the laybond rapid dpm to dry. Just thought I'd say.
ARDEX DPM 1 C can be applied where a structural damp proof membrane is not present or is ineffective. http://www.ardex.co.uk/Portals/0/DPM_NA_postcard.pdf