Specification and use of wood-based panels in exterior situations

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Certain types of wood-based panels can be used in demanding exterior situations. However, they must be correctly specified, detailed, installed and maintained, in order to provide the desired performance and service life.

Exterior use covers a wide range of situations. They may be fully exposed to wetting by salt or fresh water or be more protected with a risk of occasional wetting, such as soffits under porches or lorry decks.

This Wood Information Sheet details the considerations which must be made when specifying wood-based panels for exterior use, in particular whether a preservative treatment or protective measure is required to extend service life.



  • Exterior exposure
  • Factors affecting performance
  • Suitability of wood-based panels for use in service classes 2 and 3
  • 'Exterior' plywood may still require treatment
  • Finishes
  • Design and workmanship
  • Maintenance


This Wood Information Sheet was revised in April 2017. Changes have been made following updates to BS EN 350 and the implementation of the Construction Products Regulation.

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