Understanding Use Class 2 (UC2)

Use class 2
Use class 2

Understanding Use Class 2 (UC2)

Date Published

21 September 2021

Document Type



Use class 2

Consumer and contract law require that any product offered for sale must be fit for its intended use and a wood product impregnated with preservative is no exception.

The minimum standards for the treatment of wood are set out in British Standard BS8417 (Preservation of Wood: Code of Practice). In this standard, the level of treatment is tailored to the application ‘Use Class’ of a wood product as defined in BS EN 335 (Durability of wood and wood-based products).

Use Class 2 is for end uses where wood is used indoors, above ground and within the building envelope, but with an occasional risk of wetting (from plumbing leaks for example).

Key Information

The WPA Code of Practice for Industrial Wood Preservation (January 2021) groups the applications for treated wood into Use Classes, the main three being:

Interior: Use class 2

Exterior: Use class 3(u) and Use class 4