Your membrane can only be as good as the surface under it. Dusty blockwork, chalky render, dense concrete and lime plaster are exactly the surfaces where coatings tend to let go. The right primer gives your airtight or waterproof membrane something it can grip for the life of the building, and gives plaster something to hold onto over the top.
Three primers cover the range. Primer IM is the all-round render and substrate primer for porous or dusty surfaces before airtight coatings. Lime Prime is the bonding primer for lime renders and breathable heritage build-ups. Supergrip is the high-grip key that gets plaster and dot-and-dab to stick to cured airtight membranes, and membranes to stick to smooth ICF and concrete.
