Nexfor Ltd is working closely with the roofing industry to protect customers from substandard materials and develop new products for the domestic and commercial markets.

It is also continuing its campaign against inferior quality South American plywood which, it claims, is widely purchased by some firms.

And, alleges Nexfor, while importers and distributors seek to indemnify themselves from blame when failures occur by printing disclaimers on the products, they are well aware it is being employed for flat roofing.

Nexfor’s latest product offering is a tongue and groove version of its OSB3 product, Roofdek. Marketing and sales director Maurice Fitzgibbon explained: ‘Providing this structural interlock on the long edge effectively removes much of the work associated with installing square edge boards – in particular providing intermediate supports in the form of noggins or dwangs.’

He saids that in practice it was common that long edges were not supported – in contravention of regulatory bodies’ recommendations.

‘Unsupported edges will sag when walked on, leading to damage of the membrane. Providing tongue and groove edges respects the demands of relevant standards on the structural use of timber.’

However, said Mr Fitzgibbon, if such features were machined into the edge of Brazilian elliottii and similar South American plywood, it would not alter the fact that they carry no certification in relation to their strength or performance. And this, he said, would effectively ‘blow the whistle’ on vendors who insist the product is not being sold for specific applications.

‘What is happening is bringing the whole roofing industry into disrepute, and leaves many people open to claims when failures occur,’ he said.

Flat Roofing Alliance technical manager Paul Franklin said: ‘Nexfor is right to have asked questions about elliottii. We know there are problems with this product and we have warned the industry about it.’