What a termite management system is, and what it will not do

A termite management system is a barrier, building material or combination of methods that reduces the risk of termites reaching a home’s primary building elements through a hidden route. It cuts down concealed entry and makes termite activity easier to find. It does not make a house immune to termites.

The Queensland Building and Construction Commission (QBCC) says attacks usually start from a nest below the ground. Termites then get inside through wall cavities, cracks in mortar or concrete slabs, and gaps beside service pipes.

How does a termite barrier work?

A termite barrier works by blocking or deterring those hidden routes. CSIRO says physical barriers either prevent entry or force termites to build shelter tubes, which can reveal their presence. Chemical barriers treat the soil so termites are deterred from crossing it unseen.

Do termite barriers really work?

Termite barriers work at their actual job, which is reducing hidden entry. The QBCC says properly installed and maintained systems impede and discourage concealed entry, but they do not always prevent termites coming in the open, so they do not prevent termite attack. Installing a barrier will not stop termite activity on the site either. A system works alongside regular inspections, never instead of them.

What Queensland requires for new homes

Every new home in Queensland needs some form of termite management, and Queensland adds its own rules on top of the national building code. The QBCC says the Building Code of Australia requires all new homes to have some form of management to deter subterranean termites. In Queensland, the risk to primary building elements must be minimised for a 50 year design life. The QBCC notes termites are particularly active in hot, wet areas such as coastal Queensland.

The QBCC describes these Queensland requirements for new houses:

• Chemicals that can be topped up. A chemical system must be able to be replenished where the chemical’s life differs significantly from the building’s. For permanent houses, chemicals cannot be hand-sprayed under a slab unless proven to last at least 50 years. Where the chemical will not outlast the building and cannot be reached, a reticulation system must be installed.
• Trench and mowing strip. A chemical perimeter needs a treated trench, treated backfill, and then a concrete mowing strip 300 mm wide and 50 mm deep.
• More of the house protected. Door jambs, window frames and reveals, architraves and skirting count as primary building elements, as well as structural members.
• Access for installing, maintaining and inspecting the system.
• A licensed installer. A QBCC licence is required to install systems in new building work.

The national building code also requires a durable notice fixed in a prominent location.

Which Australian standard covers termite management?

The QBCC says AS 3660.1, Termite Management, New Building Work, is referenced in the Building Code of Australia. It is one of three parts: Part 2 deals with existing buildings, and Part 3 with assessing termite management systems. AS 3660.1 provides a range of measures, including chemical or physical barriers or a combination.

The chosen method must be shown on the drawings and specifications lodged with the building application. The QBCC also recommends an acknowledgement notice, signed with your builder before the contract, confirming you have discussed termite management. For timing during a build, see pre-construction termite protection and termite treatment for new homes and renovations.

Termite management system types compared

The two main types of termite management system are chemical and physical, with termite-resistant materials as another option and baiting used to control colonies. No single system suits every home. The QBCC says site conditions, building design and the owner’s needs, such as ongoing maintenance, all need weighing. Its homeowner guidance suggests comparing cost, durability and upkeep.

Baiting systems

This guide does not rank bait brands. CSIRO says stations are placed against infested wood or active shelter tubes, or partly buried in soil around the building. Termites that feed on the bait carry a slow-acting insecticide back to the nest and queen. Before agreeing to a baiting program, ask:

• Which product is used, and is it APVMA registered for this use?
• How often are stations checked, and what is recorded?
• What happens when termites are found in a station?
• How long does the program run, and what protects the house after it ends?

Slab, split-level and homes on stumps: what suits which

Construction decides what is practical: slabs suit chemical, stone, mesh or slab-edge systems, homes on stumps traditionally use ant caps and depend on subfloor access, and split-level homes usually need a combination.

Concrete slab on ground

The QBCC says chemical systems are normally used with slab-on-ground homes, traditionally with reticulation under the slab and around the perimeter, installed before the concrete is poured. Graded stone or stainless steel mesh can sit under the whole slab, or protect only the perimeter and the pipes through it. Even with mesh, termites can still enter through floor penetrations or the perimeter, so those areas need extra protection. If chemicals protect those penetrations, the whole under-slab area must be treated; a physical system need only protect around each one.

Queenslander-style homes on stumps

The QBCC says ant caps, the traditional protection for homes on stumps, do not stop termites getting in; they block concealed entry and push termites into the open, where an inspection can spot them. The subfloor is one of the most susceptible areas, so systems there rely totally on access, and an access door or panel must be provided. A clearance of 400 mm is generally needed under bearers, joists and pipes.

Split-level and part-slab homes

The QBCC says split-level and zero-lot-line buildings need physical systems or termite-resistant materials, and a chemical system alone may not be adequate. A combination is likely, and termite-resistant timber is especially useful for split levels. Some installers may not honour warranties where systems are combined, so check that every warranty covers the mix.

Adding protection to an existing home

Termite protection can be added to an existing home, for example as a chemical treatment around the perimeter. The Queensland rules above apply to new building work; the QBCC says AS 3660.2 is the separate part of the standard for existing buildings. CSIRO says termites can cause extensive damage if left undetected or not properly managed.

CSIRO describes how protection is usually added after construction:

• A trench is dug around the slab, stumps or footings and backfilled with treated soil.
• Under paving, reticulation should be installed so chemical can be topped up; otherwise the paving is drilled and chemical injected, called rodding.
• Service holes and slab joins must also be protected, or the perimeter treatment will not succeed.

If termites are already active, CSIRO says to avoid disturbing them, because several colony treatments rely on finding active termites. Our guide to how termites are treated explains that sequence.

Finding out what your house already has

Start with the durable termite notice, which is usually in the electrical meter box. The QBCC says owners should find out what system their home has, and if you bought the house, the onus is on you as buyer to learn its maintenance requirements. Work through these checks:

1. Read the notice. The QBCC says it should state the method of protection, the installation date, the chemical’s life expectancy from the APVMA label, and how often to inspect and what to check.
2. Find the builder’s documents. When building work is finished, the builder should give the owner details of the system and the owner’s maintenance responsibilities.
3. Check the pre-purchase report. A pre-purchase timber pest report should comment on any signs of previous timber pest treatments.
4. Book an inspection. A termite inspection can confirm what is visible and accessible, though the QBCC notes any inspection is limited by areas that cannot be reached. See termite inspection and treatment for how the two fit together.

Who may install it in Queensland, and why DIY falls short

In Queensland, a contractor needs a QBCC Termite Management licence, chemical or physical, to give advice or reports on termite management or to install systems in new building work, and chemical work also needs a Queensland Pest Management Licence. The QBCC says a contractor needs one of these licences to give advice or reports on termite management systems or infestations.

The QBCC chemical class covers pre-slab and perimeter chemical treatment of new building work, and anyone doing it must also hold a Pest Management Licence issued by the Department of Health. The physical class covers installing the particular material or system named on the licence, to the manufacturer’s specification. You can run a free licence history check on any contractor at qbcc.qld.gov.au.

Can you do a termite barrier yourself?

On new building work, the QBCC says a QBCC licence is required to install termite management systems. On an existing home, CSIRO notes owners can buy termite products, but careless use can disturb termites and drive them away only temporarily. The QBCC says the most frequent cause of infestation is a perimeter system that has been bridged or breached.

What owners must keep doing

Have your home inspected at least every 12 months by a QBCC-licensed termite contractor, and keep the system intact between visits. The QBCC recommends more frequent inspections in high-risk areas, such as near trees or bush. It also warns owners not to disturb or breach their system, to keep their warranty and insurance entitlements.

• Book a professional inspection at least annually, and check around the house yourself between visits.
• Keep garden beds, turf, paving, bark and wood chips away from the house wall and slab edge.
• Leave at least 75 mm between the bottom of any weep hole and the garden bed, concrete or paving.
• Do not attach unprotected carports, pergolas or fences to the house. Freestanding structures need at least a 25 mm inspection zone.
• Do not stack timber against the house or place water tanks across the treated zone.
• Top up chemical zones and reticulation as the termite notice states.
• Keep the notice, builder’s documents and inspection reports together.
• Recheck the system after renovations, new paths or new underground services. CSIRO says a gap where a new slab meets an old one must be sealed or protected.

Next steps

Our guide to what drives the cost of a termite barrier explains the main factors. When you are ready to have your own home assessed, see our termite inspection and treatment service. Bob Gunn Termite Solutions holds QBCC licence 894337, and quotes are free.