The Building Code of Australia requires all buildings that contain structural elements susceptible to termites to have termite barriers installed as per the Australian Standard 3660.1-2000.
You may think that this offers protection against termite attack, however this is not so. Termite barriers do not prevent termite attack. So what do they do? They aid in the detection of termites by forcing termites into an inspection zone where they can be detected. Termite barriers, whether they are physical or chemical, constructed of metal, plastic, concrete or stone, are designed to prevent termites from gaining concealed entry into a building, so when they track around the termite barrier the mud galleries are exposed, allowing the inspector to see the termite workings.
Unless regular termite inspections are carried out to the property, the termite barriers installed during construction will not provide any protection against the damage caused by termites. Often homeowners will not have regular termite inspections, assuming that this long-lasting termite barrier will protect them against termite attack and the resultant damage.
Unless the pre-construction termite barrier is properly installed, an infestation can be impossible to detect until major damage is caused and results in some kind of structural failure, even if termite inspections are regularly conducted.
If termite barriers are installed where the inspection zone cannot be seen, they serve no useful purpose. This is commonly the case in terraced houses where termites can gain access from the neighbouring property above the termite barrier.
To be effective the termite barrier must be continuous; if the termite barrier is not continuous it is like a sheep paddock where only three sides of the paddock are fenced. The fence serves no useful purpose because the sheep can simply walk out the side that is not fenced. If termite barriers have gaps or are not complete, termites will gain concealed entry between the termite barriers and avoid detection.
Often when houses are extended it is very difficult to install effective termite barriers. This is because the termite barrier between the original house and the extension cannot be properly integrated or made complete. When a house is extended, the risk of termite attack along the interface between the original house and the extension is always very high.
Termite assessments and Barrier construction
At Pestforce we often carry out assessments of termite barriers installed during construction to ensure that they comply with the appropriate Standard. Unfortunately we usually find that they do not and are not continuous or complete, or that they are inappropriately installed. Often the wrong termite barrier is chosen for a particular site or construction method, leading to difficulties at installation time.
We also find that poor planning and design is often the reason for the failure of the termite barrier to prevent concealed entry into a building. If the architect fails to take account of the termite barrier design when looking at how landscaping will be done, the termite barrier can be easily bridged, providing termites with concealed entry. Our consultants often assist architects and builders with sensible designs to reduce termite risk and allow the installation of more effective termite barriers and termite management systems.
When attachments such as paths, patios, hot water systems and air conditioning are made to a house, the termite barrier is not taken into account and is bridged or breached, providing termites with concealed entry.
Every home should have one
It is important that homeowners are aware of the termite barrier because they often bridge or breach it unwittingly, exposing their homes to concealed termite entry and damage. Usually a notice will be placed in the meter box of the house advising which termite barrier is installed and what should be done to maintain it. Termite inspectors look for these notices so that they can find the inspection zone and look for evidence of termites crossing it.
The termite barrier is the last line of defence against termite attack. They only detect termites and are only part of the termite management that every house should have. In addition to the termite barriers, the builder should be checking all trees and stumps for termite colonies prior to construction. The builder should be planning and consulting with the building designer to ensure that an effective system is installed. The most common mistake is that a builder is given a set of plans and a specification simply asking for termite protection to be installed as per Australian Standard 3660.1-2000, so he simply rings his particular pest manager who attends the site and installs the system or product he is using at that time. This often results in bad outcomes because no consultation is entered into, and inappropriate termite barriers are installed.
As termites damage so many homes, consider carefully how to protect any new home. Just because a house is new does not mean it will not get termites. Invest in termite management prior to construction, during construction and post construction; don't make the mistake of waiting for something to happen first.