Termite management systems

posted: 10/Nov/2015

 

Australian Standard 3660.1 provides a range of options for termite management of new buildings from subterranean termites. These include:

Ant Caps (Termite Shields)

These are physical management systems that are inserted between the lowest floor framing timbers and the supporting stumps, brickwork, piers etc. They are usually formed from corrosive resistant sheet metal or mesh and are designed to force the termites out into the open and to allow physical inspection and simple, early detection and eradication of termite activity.

Concrete Slab Systems

A good quality monolithic slab (no cracks or construction joints) designed and constructed to AS 2870 provides a physical management system. Where construction joints or service penetrations occur, other forms of physical or chemical barriers must be provided. Exposed slab edges (min. 75 mm) around the perimeter of the building provide for physical inspection, detection and eradication.

Chemical Systems

Chemical management systems provide a zone of treated soil, poisonous to termites, under footings and slabs and/or around the perimeter. Chemicals registered for termite protection include organophosphates and synthetic pyrethroids (modified). These chemicals have varied life expectancies (refer to product label & directions), depending on soil and exposure conditions, and will therefore require replenishment at regular intervals.

Reticulated Chemicals

Chemicals may require a reticulation system to permit retreatment in inaccessible areas, i.e. under slabs. This requirement is mandatory in Queensland. These proprietary systems use a piping and distribution network installed at strategic points under concrete slabs and around the perimeters of buildings. At completion of construction, chemicals are injected to reach each distribution point. Retreatment can be applied at any time.

Chemically Impregnated Membranes

Underslab and perimeter protection can be provided with a termite management system where a vapour barrier membrane is laminated to a synthetic fibrous web impregnated with synthetic pyrethroid or other termiticide.

Stainless Steel Mesh

This system consists of a fine woven marine grade stainless steel mesh used as a physical management system. The stainless steel mesh is too small for termites to pass through and too hard to chew through. The mesh can be under the entire concrete slab or as a partial system in conjunction with a concrete slab barrier, that allows for construction of a perimeter barrier only, with sleeves and clamps to seal around service penetrations. The mesh can also be formed into ‘socks’ for stump/post applications.

Granular Materials

These termite management systems can be used under slabs and/or around posts and footings. The system is comprised of finely graded granular materials of particle size and voids designed to prevent termite passage, i.e. voids too small to pass through and particles too large for termites to move. These systems may not be recommended for protecting buildings against Mastotermes spp. and therefore may not be suitable for use north of the Tropic of Capricorn.

For more information ask your local Accredited Queensland Merchant Network member for a copy of Timber Queensland Techncial Data Sheet #12 - Termite Management of New Buildings.

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