How Long Does a Termite Barrier Last?

Before we talk about how long a termite barrier lasts, it is important to define what a “termite barrier” is!

When most people ask this question, they are referring to a termite chemical barrier – a termite treatment to the soil around a building. However, there are also physical barriers, which are installed during building’s construction, as part of the termite protection measures.

We’re going to focus on chemical barriers. But first let’s discuss what a chemical “termite barrier” is…

The term termite barrier is an easy concept to visualise. Chemical is put in the ground creating a chemical barrier, an invisible force field, which the termites cannot pass. In reality that’s not how modern termiticides work. Termites cannot actually detect the modern termiticides and this is by design. When encountering the chemical in the soil they cannot detect in a start burrowing into the soil. In doing so they pick up the insecticide and die. Their nest mates respond to their death by blocking off the forgaging tunnel and therefore preventing access to your house. Termite treatments to the soil and therefore better called a treated zone rather than a termite barrier.

So, how long does a termite treatment last?

There are four main factors that influence how long a termite treatment will last:

1. Type of chemical
2. Temperature
3. Soil type
4. Rainfall

Different chemicals will last different lengths of time, before they breakdown. In fact, different formulations using the same insecticide can last different lengths of time. The manufacturer will have tested the product during the development process to prove how long it lasts. This data is then assessed by the regulatory authorities before the product is approved. The duration of protection is specified on the product label.

However, the duration of protection will be influenced by local conditions, and your pest professional will modify the duration of the warranty accordingly.

Temperature has an impact on degradation rate. The higher the temperature, the quicker the chemical breaks down. Chemicals will last longer in the south (Melbourne) than up north in the tropics (Darwin). Sydney is about average.

Soil type also has an impact on the rate of breakdown of chemicals. Typically, more alkaline soils cause chemicals to break down quicker. However, perhaps the bigger impact of soil type is its water holding capacity. Clay soils which get water-logged can cause chemicals to breakdown quicker and sandy soils with high rates of drainage can cause chemical to get washed away quicker. This is why, during a termite treatment, it is sometimes necessary to replace the natural soil around the home with a sandy loam soil, which gives the best performance.

The amount of rainfall also has a big influence on how long a treatment lasts – the more rain the shorter the duration of treatment. In addition, if a property gets flooded, it is normally necessary to get a full retreatment. Not only can the product get washed away, but soil and sediment can be deposited on top of the treatment, making the barrier ineffective. (Some, but not all, home insurance policies will cover a termite re-treatment in these circumstances).

Although some of the products state the product can last 8 years or longer, due to the variables mentioned above, at Serial Pest Control we offer a 5 to 8-year warranty for our termite treatments, depending on the situation. It is also important to have annual termite inspections to maintain the warranty – this it to make sure the termites haven’t found a way around the barrier and that the barrier hasn’t been compromised, for example by construction or landscaping work.

How long do termite physical barriers last?

Termite physical barriers are installed during the construction process to protect gaps in the building construction elements that may allow termites to enter without being noticed. An example would be the use of hard plastic collars around utility pipes, to eliminate the gap between the pipe and concrete slab. These physical barriers are designed to last the lifetime of the building (nominally 50 years). However, sometimes they can get compromised by renovations or other building activity. This is another reason why annual termite inspections are also required to maintain the warranty on any physical termite barriers installed on new constructions.