When it comes to protecting homes from termites, people often talk about “termite barriers”. But what is a termite barrier and how do they work? There are two types of termite barriers – chemical termite barriers and physical termite barriers. Chemical termite barriers are applied to the soil, and physical termite barriers are incorporated into the construction of the building.
People like using the word “barrier” as it’s easy to understand and visualise – it’s something that stops termites from entering your home. However, it’s important to realise that any barrier treatment is only designed to protect a weak point in the building’s termite defence system. They are designed to protect concealed termite entry points (potential entry points underground that you cannot see). Termites can still potentially build around these protection systems, but when they do so their activity becomes visible (above ground) and they can be spotted. This is why even with a termite barrier in place it is essential to have an annual termite inspection.
Chemical Termite Barrier
Chemical termite barriers are also called termite soil treatments. In the industry we prefer to call these “treated zones”, as the word “barrier” gives the impression they work like a force field, and that’s not how all the products work.
The older type of soil treatments (which still exist) are repellent to termites. Termites can detect their presence in the soil and they are repelled. These can be considered to be a true barrier, as the termites will not dig into the treated soil. The potential weakness with these treatments is that if there is a small gap in the treatment, the termites could find it and still get into the building. If applied correctly to achieve a continuous treated zone, these treatments do work well. However, when injecting under hard surfaces it is impossible to know whether there are any gaps in the treatment, which could create potential termite entry points.
The newer types of soil treatment use “non-repellent” chemicals. As their name suggests, termites are not able to detect their presence in the soil. Instead, as soon as they start tunnelling into the treated zone, they pick up the insecticide and die shortly afterwards. The key advantage with these treatments, is that as termites cannot detect their presence, which means they cannot detect if there are any gaps in the treatment. As a result, the chances of them passing through a gap in the treatment without also encountering some treated soil is virtually zero. Termidor is the leading “non-repellent” termiticide on the market – these treatments are the gold standard in termite soil treatments.
How to install a termite barrier…
Correct application of a termite chemical barrier requires all the sub-soil entry points to be protected. This requires the soil around the building to be treated (to the depth of the footings) and if the house is built on piers, the sub-floor soil also needs to be treated. If there are pavers around the home, these need to be lifted to treat the soil, and any tiles or concrete needs to be drilled so chemical can be injected to treat the soil underneath. Certain types of concrete slab homes may also require the internal edges of the concrete slab to be drilled and injected to protect hidden entry points.
Termite Chemical Barriers in Brisbane
The termite pressure in Brisbane is very high and so termite chemical barriers are the most popular termite treatment. Whilst termite baiting systems are the only option for some buildings, termite soil treatments provide robust, long-lasting protection. At AllPro Pest Control, we generally recommend Termidor termite treatments. It is the leading product on the market and had protected hundreds of thousands of homes over many years. In Brisbane, a Termidor treatment can last for up to 8 years. As a Termidor accredited applicator, we are also able to offer the $2 million Termidor Assurance Warranty on qualifying treatments.
Physical Termite Barrier
Physical termite barriers are solid products that provide a physical barrier to termite entry and are installed during the building construction. They are designed to integrate with the physical features of the building to seal any gaps which could become concealed termite entry points. Each type of building construction has different areas to protect. Many older homes are houses on piers and many people will be aware of the metal “ant caps” at the top of the brick piers in their sub-floor. However, most newer houses are built on a concrete slab.
Concrete Slabs as Termite Barrier
Most people would view a concrete slab as a very effective termite barrier. However, there are a lot of weak points in a concrete slab, and unlike a house on piers, you can’t get underneath the concrete slab to see what’s going on. Certainly, a quality concrete slab should not crack (but poor-quality ones do and create termite entry points), but all concrete slabs can have potential gaps around any utility pipework that enters through the slab (e.g. drains). These gaps need to be sealed with collars when the slab is poured. Sometimes there are also joints or step-downs in the concrete slab, these also need to be protected. The perimeter wall also needs to be protected if the edge of the concrete slab is not visible. If the base of the perimeter wall is below soil level, termites can easily enter without being noticed. In such cases, termite sheeting needs to be installed into the perimeter wall during construction at a level that will be above soil level after construction.
Main types of physical barriers
Plastic / Polymer Sheeting
These sheet materials (sometimes multi-layer, often impregnated with insecticide) are installed under concrete slabs and at the base of perimeter walls during construction. There are a range of brands, including Homeguard, Kordon, Greenzone and Termseal.
Metal sheeting
Metal sheeting materials (such as Termimesh) can be installed at the base of perimeter walls during construction.
Ant capping
For houses build on piers, metal “ant caps” are installed on top of the piers before the floor joists are placed, to prevent termites moving up inside the brick pier. They can still build their mud tubes around the outside of the metal ant cap, but this activity will then be detected during a termite inspection.
Termite Collars
Plastic / polymer termite collars are placed over utility pipes that enter through a concrete slab before the concrete slab is poured. When the slab is poured, these collars will seal any gaps between the pipe and the concrete. They can be either solid or flexible collars, with or without impregnated insecticide.
Paints and foams
A range of polymer paints and foams can be used to protect potential termite entry points where a more flexible option is required. These paints and foams also contain insecticides.
Termite Barrier FAQ
How long does a termite barrier last?
How long a chemical soil barrier lasts depends on the type of chemical used, the soil type, temperature and rainfall levels. In Brisbane, a Termidor treatment should last up to 8 years.
Physical barriers are designed to last “the lifetime of the building”. Products with CodeMark certification certifies that the product has a working life and durability of at least 50 years. However, products do age and can become compromised for a variety of reasons. Annual termite inspections are still essential to ensure protection measures are still working.
How much is a termite barrier?
Physical termite barriers are costed prior to construction. The price depends on the construction type, the products used, the length of the building perimeter and any concrete slab entry points or sub-floor piers to be protected.
For termite chemical barriers the cost depends on the size of the house, the construction type, the depth of the soil to the top of the footings, how much of the building perimeter is covered with hard surfaces (which need drilling and injecting) and the type of the product used. A quality treatment from an experience termite company in Brisbane would start at around $3000 for a typical 4-bedroom house on a concrete slab.