8. Bonding GRP to other materials




GRP bonds very well to asbestos but the asbestos must be clean and dry. We do not recommend power washing or abrading asbestos (it produces dangerous slurry or dust) and we strongly recommend engaging an asbestos professional for advice.

Bituminous surfaces (bitumen, felt and asphalt)

Bitumen inhibits the cure of GRP but on small areas it can be neutralised by a coat of G4. Applied with a brush or short pile roller G4 will initially soften the bitumen and will then harden off sufficiently to accept a GRP laminate – but it is much better to replace the boards or even overboard with 18mm OSB3 Sterling. We do not recommend laminating onto asphalt which must be over-boarded before applying a GRP laminate.

Contact us for further advice on bonding to unusual substrates.

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