Ideal for timber framed homes, no need to plasterboard

Bonding plaster for use with polyurethane foam

People often ask us if the foam can be rendered onto to save the need to line out with plasterboard. A typical example is a timber framed house where the foam is applied in between timbers which are to be left exposed. We would apply the foam to such a thickness so that the render can be applied and still preserve the appearance.

Our supplier recommends a product called Carlite Bonding Plaster, available from many DIY outlets and building suppliers. The trade name is Carlite though it is also known as Thistle Bonding Plaster.

The bonding plaster can be used straight on top of foam, though we must recommend to the customer that they do a small test area with just bonding plaster on top of foam, and another test area with PVA bonding primer followed by the plaster as an extra precaution.

Ideally, even though it involves more work, a coat of PVA bonding primer would be applied to the foam, then left to dry, followed by the Carlite / Thistle Bonding Plaster.

The average price for a 25KG bag is £7.00 or thereabouts. Wickes stock this over the counter.