Roofs experience wind, precipitation, solar heat, temperature changes and moisture from both inside and outside. For that reason, roof insulation boards cannot be selected on thermal performance alone. The board’s intended function, exposure conditions, vapour behaviour, fixing and interface with every adjacent layer need to be understood before it becomes part of a specification.

Nordic Fibreboard’s range includes wood-fibre softboards that may be used in documented roof applications. Wind Barrier Board – ISOplaat and ProWind – ISOplaat are relevant where the construction needs a wind-protection layer that helps limit unwanted air movement through insulation. ISOplaat and ISOmodul insulation boards can be considered for suitable thermal or acoustic layers, subject to the exact roof design and product documentation.

These roles are different. A wind barrier helps the insulation perform as intended by reducing air movement, but it is not automatically the roof’s primary waterproofing or airtightness layer. An insulation board adds thermal resistance, but it is not a structural deck and should not be walked on over unsupported spans. The roof covering, underlay or weather-resistive layer, air and vapour control, ventilation spaces and load-bearing structure must each be designed and installed for their own function.