Primed H4 eXtreme Joists
- H4 treated pine
- Double-primed
- Ideal for extrememly low decks
- Protection against insect attack and fungal decay
eXtreme Timber products use a blend of new technology and time-proven methods to create timber products that perform in the extreme Australian environment.
eXtreme Joist is perfect for those sleek, low-to-ground decks. Using radiata pine which is one of the most versatile building products available on the market while boasting H4 Copper Azole treatment protecting it from insect and fungal decay. The H4 Treatment by Lonza in eXtreme Joist utilizes BARamine® technology for improved penetration in the wood which equals better protection.
What applications are H4 eXtreme joist for?
When decking is less than 400mm off the ground, additional consideration to ensure adequate performance and service life of the timber is required. This includes increased ventilation, sub-surface drainage, and increased timber durability/preservative treatment.
Any framing timbers on the ground or lower than 150mm are required to be termite resistant and in-ground durability Class 1 or preservative treated to H4 or better.
Preparations
It is important that the ground beneath a deck is completely cleared of all building rubbish, garden debris and obstructions to water or air movement. Water must not be able to pool under the deck and the ground must be sloped away from the foundations of the house. Agricultural drainage pipes may be required in some instances so water can properly _ow away from beneath the deck.
Even though eXtreme Joist are H4 treated, it should not be subject to permanent contact with fresh water, if the timber will be in permanent contact you will require H5 or higher.
When on ground, It is best practice to install your joists/bearers onto pedestals or packers to allow for cross _ow ventilation under the sub frame. This will also limit the chance of trapping water under your deck.
Plastic sheeting acting as a waterproof membrane should be placed on the cleared ground. If timber bearers are to be placed directly on the ground, the plastic sheet should be covered with compacted gravel or sand to provide a solid base.