Service · barriers

A barrier is there to make concealed entry harder to miss.

The QBCC describes a termite management system as something that minimises the risk of damage to primary building elements through a concealed route. Installing one does not stop termites being active on the site.

What the new-building standard is for

AS 3660.1:2014 sets requirements for designing and building subterranean termite management systems for new buildings and new building work. The Standards Australia preview says it includes physical and chemical options, used alone or together. It also says the measures cannot guarantee that a building will never be entered or will never suffer attack, and that a system built to the standard can still be bridged or breached. The same preview says the standard does not cover existing buildings, drywood termites, or durability, maintenance and inspection procedures.

QBCC says the Building Code of Australia, as it applies in Queensland, requires the risk to primary building elements to be minimised for a 50-year design life. Compliance with systems in AS 3660.1 is one way of meeting the deemed-to-satisfy path in Part 3.1.4 for houses and associated Class 10a structures, read with the Queensland variation.

Chemical systems and the replenishment rule

QBCC’s Queensland variation note says a chemical system whose life is significantly shorter than the building has to be replenishable. For non-temporary Class 1 buildings, chemicals cannot be hand-sprayed unless it can be shown they will last at least 50 years. Otherwise a reticulation system may be needed under a slab. Perimeter chemical systems, on that note, are trenched, treated, backfilled, treated again, then finished with a 300 mm wide by 50 mm deep concrete protection layer.

AS 3660.1, as QBCC describes it, does not name a brand of chemical. It allows a chemical registered for the purpose by the APVMA. QBCC says most chemicals have a limited life and that owners should ask the manufacturer about life expectancy and label conditions. A QBCC Termite Management — Chemical licence is required for chemical termite work of any value, not only work over $3,300. The licensee who applies the chemical also needs a Queensland Health pest management licence. SEQ Service Quotes holds neither.

Physical systems

QBCC describes several physical approaches for new work:

• Ant caps on stumps and piers, which do not stop termites but force them into view.
• Graded stone particles, which the QBCC licence class for physical systems is restricted to, along with stainless steel mesh.
• Stainless steel mesh under a slab, at the perimeter, or around penetrations. Termites can still use an unprotected penetration or the perimeter, so those points need their own treatment.
• An exposed concrete slab edge, which does not stop entry but is meant to show it. QBCC says penetrations through the slab still need protection.
• Termite-resistant materials, including steel, concrete, naturally resistant timber in Appendix C of AS 3660.1, and preservative-treated timber in Appendix D.

Queensland extends “primary building element” to door jambs, window frames and reveals, architraves and skirting, as well as structural members. A system that only talks about wall frames can be the wrong scope for a Queensland house.

The durable notice

QBCC says the Building Code requires a termite control notice fixed in a prominent place, such as the meter box. It should state the method, the installation date, the life expectancy of a chemical from its APVMA label, and the installer’s recommendation for later inspections. If a house has no notice, that is a reason to ask a licensed person what was installed. It is not, by itself, evidence of termites.

One starting price

Jets advertises a standard-house barrier from $3,960 on its Brisbane and Ipswich page. “From” is a starting advertisement, not a quote for your slab, your split-level plan, or a combination of mesh and chemical. QBCC says the cost and the effective life of methods vary considerably, and so do ongoing costs. Ask what is included, whether GST is included, and what voids the warranty. A combination of systems can be a problem for warranties: QBCC notes that some installers may not honour a warranty where systems are combined.

Homes and garden beds bridge systems when soil, mulch or paving covers the inspection zone. QBCC recommends at least 75 mm from the bottom of a weep hole to the top of a garden bed, concrete or paving, and care where a fence, carport or water tank is fixed to the house.

Barrier types compared · AS 3660 overview · Cost guide · Homeowner checks