As with most industrial grown timber, South African timber is not very durable and is subject to attack from fungus and termites. This is why it is necessary to ‘treat’ timber with wood preserving chemicals if you require confidence in its durability. Taking this a step further, SAWPA together with the SABS and representatives from the timber industry established different “Hazard Classifications”. The most common hazard classes that one would usually come across will be H2, H3 and H4.
The timber bought at the general hardware and the timber in your roof at home will be treated to H2
Wooden cladding for houses, fencing, Decking and balustrading should be treated to H3
Wooden posts, gum poles and timber making contact with the ground should be treated to H4
You need to ask yourself the following questions:
- Is the timber that you are buying going to be under cover, for example in the roof of your house?
- Are you building a fence or a deck?
- Will this timber have contact with the ground?
- Or is it going to be submersed in fresh water?
- Maybe even salt water?
Each one of these situations requires a different amount of chemical in order to preserve the timber for any period of time.
This is where the hazard classes come into play. These hazard classes make it easier for the man in the street to understand and to have peace of mind that his timber will give him as long a life span as possible.