Bona® R540 Moisture Barrier/Primer is a one-component roll-on moisture membrane specially designed to mitigate vapor transmission on absorbent and non-absorbent subfloors. Only one coat needed when used with 1250G or 1500G trowel and any Bona Adhesive. Two coats required in all other installations when the above criteria is not met.
- Helps mitigate potential moisture issues, like cupping, originating from below the membrane, in new and existing construction
- Can be used as a vapor retarder in place of felt paper for wooden subfloors up to 20% MC
- One coat can be used for damp proofing concrete subfloors up to 95% RH & 18 lbs
- Dries fast allowing nail-down installation immediately
- Easy to apply – rolls on
- Suited for underfloor heating