Step 4: Quality of System Installation

A system is only as good as the quality of its installation. The following points highlight some
key issues:

• Where possible use one contractor to install the entire termite management system to reduce confusion about accountability for quality.

• Before beginning the building, care must be taken to clear the footprint area of tree roots, stumps, logs, loose timber and other termite food sources.

• Check that the ‘Termite Management Notice’ containing system information has been fixed to the building before allowing the installer to finish onsite.

• The approving authority may require certification from the installer stating that the system complies with AS3660.1. This certificate is a good thing to have in the project records as well. It replicates some of the data in the previous ‘Termite Management Notice’. Extra information includes chemical barrier details on the concentration and volume of chemicals, the name of physical barriers and methods of installation, if the barrier is a single or integrated system, a diagram showing the location of the barrier, limitations of the barrier or the ability to maintain or inspect it, and contact details for further information on the system installed.

• For concrete slabs used as physical barriers, cracking and air voids present concerns for hidden termite entry. AS3660.1 states that cracks passing through slabs must not exceed 1 mm. To avoid problems, mechanical vibration of concrete is recommended throughout the slab, edge beams, etc. Good curing practices will also help.

• Pay special attention to slab edge detailing and vibration where concrete slab on-ground floors include a split level (formed by concrete upstand or masonry retaining wall).

• Rigorously protect barriers from damage during construction e.g. don’t allow sand/mortar to contaminate crushed stone barriers, carefully parge any penetrations through mesh barriers.

• Joints in concrete slabs represent another path for hidden termite entry. Avoid joints if possible. If not, consider using special barrier details along the joint line, e.g. stainless steel mesh.

• Chemical barriers pose a concern in terms of the quality of chemical application. AS3660.1 provides a test regime that can check the quality of application but unfortunately it is not a realistic test for day-to-day site checking. It is perhaps best to use reputable companies who conduct their own checking regimes, and seek periodic reports on their test results.

• Sub-floor ventilation is often poor, especially cross flow ventilation. Ensure good ventilation by regularly spacing vents and using vents with sufficient cross sectional area. If possible check the work from the inside looking out. Being able to see daylight through the vents (or lack thereof) helps identify problems.

• Professional indemnity insurance is increasingly required of system installers, and offers a significant form of quality control against defective work. Its attainment is often conditional upon installers maintaining professional development education, thus assisting installers to maintain up to date knowledge.

• Use installers licensed under government fair trading legislation where operational (e.g. Queensland Building Services Authority).