Timbers in schedules A, B and C are allocated individual natural durability ratings for above-ground and in-ground situations, in accordance with AS 5604-2005 Timber—natural durability ratings.

A rating in brackets e.g. (2) indicates a provisional durability rating.

Above-ground durability ratings system for heartwood:

    Durability class 1. Above-ground life expectancy >40 years
    Durability class 2. Above-ground life expectancy 15 to 40 years
    Durability class 3. Above-ground life expectancy 7 to 15 years
    Durability class 4. Above-ground life expectancy 0 to 7 years

See the guide: Natural durability ratings