Treated timber is where it has been treated with a preservative to improve the timber’s resistance to attack by wood destroying fungi and insects. In other words, the timbers durability is enhanced to a level which is suitable for the intended use. However, such treatment does not always provide the timber protection against weathering.

It is Highly recommended that you use a minimum H3 for your Timber bearer and joists; H3 Treated is for Above Ground usage.

Should your deck require ground contact it is recommended that you look at H4 Treated. Please refer to our Low Deck Range for this option here