A Comparison – Chemical Treated Zones V The Green Termite Baiting System

/ / Pest Talk

Choosing the best method to protect your home from termites is never easy. There are so many choices of product and quite a few different methods. In a previous newsletter we recently discussed the best way to build a termite-proof home from scratch and we pointed out the strengths of building your home on piers/stumps. This method of prevention is generally referred to as a physical barrier and works by making it more difficult for the termites to enter undetected.

However, most of us have existing homes and it would be preposterous to consider lifting them off the ground to create a physical barrier. If you are shopping around for some long term termite protection then your professional termite man will most likely offer you one of two standard choices. Either:

  • A chemical treated zone around the entire home.
  • Or a termite baiting system around the entire home.

There are pros and cons to both methods of protection. It is not a case of one is right and one is wrong. Both systems work well when used appropriately and installed correctly. In some cases one method will have major advantages over the other method and vice versa. Quite often a combination of both methods may offer the best overall termite protection plan. We recommend that if you are seeking long-term termite protection for your home that you discuss your options with an unbiased licensed pest control company that offers both methods of protection. They should be able to offer you a termite protection plan that is best suited to your home and clearly explain to you why they feel the solution that they are proposing is the more appropriate one for your home.

That said; let’s begin with the pros and cons of each system.

The Chemical Treated Zone

If your home is built on naturally flat ground with rich organic soil to a reasonable depth all round, then a chemical treated zone is likely to be your best option. The advantages will be that you can do it once, for a reasonable price, and it will probably be 5 to 10 years before you even have to think about doing it again (provided there is absolutely no disturbance to the treated soil i.e. Gardening, pets digging, extreme weather). Termites will find it very difficult to get into the home whether the chemical is of the non-repellent or repellent variety.

Unfortunately there are very few homes in Australia that sit on the bed of rich organic soil. For starters, the Australian bush is naturally harsh. Topsoil is thin and only the hardiest native plants can survive. If you have ever sighted new land being developed in any of our major cities, you will note that the majority of housing sites are located on barren earth that has been scraped and levelled by bulldozers. If there was any topsoil to start with, it is long gone. What is left is usually rock and shale or clay which is poorly suited to retaining any chemical.

To help combat this, many new homes have reticulation systems installed which allows the chemical to be refreshed on a regular basis. Ideally the reticulation should be installed in quality soil, but in general it is installed with nothing more than the rubbish soil that the home is built on. This is why so many new homes still get termites in the first five years of their life despite the chemical treated zones that are put in place when the house is built.

Clearly the biggest problem with a chemical treated zone is getting an even and thorough distribution of the chemical throughout the soil around the perimeter of the home. It is a poor reflection on our housing industry that despite the government’s efforts to implement a set of standards that should ensure the protection of new homes from termites, the majority of new homes are still built with major weaknesses that termites can exploit to gain entry. A building site is a pretty messy place during the construction of a home. Few builders (if any) will bring in quality soil to be placed around a slab.

Pathways, paving and concrete usually end up being laid beside the walls of most new homes to a cover a multitude of sins – rocks, clay, broken tiles, broken bricks, beer cans, drink bottles and other odds and sods – none of which are able to hold termiticide and all of which open a pathway for termites to enter the home at a later date. When termites are found later on in the life of the home, this same concrete needs to be (ideally) cut (not drilled) and the rubbish soil needs to be replaced with some quality soil, the termiticide applied according to the label and the concrete re-laid which is both expensive and quite a lot of trouble.

Whilst on the subject of new homes, we would be remiss if we did not mention that many homes are protected by plastic sheeting which is impregnated with termiticide. The plastic is laid over the soil and the concrete slab is poured on top of it. The big advantage of this method is that it presents both a chemical and physical barrier to termites. Given enough time the chemical will degrade as will the plastic. However, there should be many years of termite protection if the plastic is laid correctly so that it seamlessly covers all potential termite entry points between the slab and the frame of the home. In some cases, poor workmanship undoes it all.

Another popular construction technique at present is the ‘Waffle Pod’ slab. It’s popular with builders because it’s cheap and easy compared to a ‘Monolithic Slab’. Regular readers of this newsletter will know that if it’s cheap and easy then it may not be ideally suited to termite prevention. The waffle pod is generally made from a block of polystyrene foam (termites love to nest in polystyrene) placed on a flat prepared site, there are no footings associated with this type of construction as it floats on the surface of the soil, therefore it is impossible to apply a chemical treatment in accordance with the requirements of Australian Standard AS3660.2 which states that the soil must be trenched to 50mm below the top of the footings. You will find that (when the time comes, as it likely will) remedial termite treatments on waffle pod homes will never receive a warranty.

This and many other types of construction these days are additionally fitted with ‘Physical Barriers’ and most people think that they are totally protected from termites. Unfortunately, physical barriers are designed to force termites to visibly expose their presence by building their mud leads over the edge of the barrier (just like the old ant caps on the stumps). They are not designed to stop them. However, inside the house, the edge of the modern physical barrier is typically covered by carpet or tiles. On the outside, the wall is often rendered which also covers/conceals the physical barrier. You see the problem?

The preceding paragraph is a very simplistic explanation of the very complicated process of properly installing a physical barrier. Don’t take this the wrong way; properly installed physical barriers are very effective for their role in termite prevention, however… because they are complicated, there are many steps in the process where they might fail through no fault of the product or installer.

Returning to our subject; the biggest problem with the chemical treated zone is that they are difficult to install correctly. For existing homes it involves trenching the entire perimeter of the home and ensuring an even spread of termiticide from the footings to the surface. In general they are expensive especially if they are done by the book (to the Australian Standards). Too often, corners are cut which in turn reduces the effectiveness of the chemical treated zone and increases the chances of failure.

The most common risk that is taken is when concrete is drilled and injected. This method is used mainly because the homeowner does not want to go through the inconvenience and expense of having their concrete (paving/pathway/tiles/etc) cut and removed then repaired/replaced later. To be fair, drilling the concrete is quite often perfectly successful and in some instances it is the only viable option. The problem is that one can never be sure of what is actually under the concrete. Inevitably it is the homeowner who has to weigh up the risk versus the cost when selecting a method of termite control, and too often ‘price’ rather than ‘quality’ is the deciding factor.

Once a chemical treated zone is set up correctly it’s important to ensure that the treated zone is not breached by the addition of untreated soil or by the stacking of items against the wall of the house. It’s amazing to see some people actually stack their firewood against the wall of their home and not give a second thought to termites. There is one intrusion that may develop that is not so obvious. It is tree roots. Trees can grow considerably in a five-year period and if a nearby tree is too close to the home it is possible that its roots may go through the treated zone and under the slab of the house which in turn may allow termites similar access. So think about the trees that are around your home; where do their roots go? If you’re planting trees be sure to position them in a safe place away from the walls of the house. It may pay to do a little research on the Internet before you buy trees. It is common to see umbrella trees close to homes and although they are very beautiful above ground, their root system is a nightmare both from the point of view of termite problems as well as their well-documented interference with drainage pipes.

If you have any old tree stumps on your property it is also important that you consider where their roots remain; are they giving termites access to under the slab? Over the years, our company has trenched around a great many homes. Tree roots are commonly found, and when they are, we saw them off and remove them. If however they are underneath concrete and the concrete is only drilled and injected, then the tree roots remain in place which offers termites a clear and protected route back through the chemical treated zone to your home.

Another factor that comes into play is the type of footings that the home sits on. If the footings are too shallow because the home is bedded on rock or shale then the chemical treated zone is only going to be an inch or two thick which is unlikely to last very long. If the home is on a sloping block, it is very difficult to build a continuous treated zone because the footings will be deep in some places and shallow in others and usually there is a lot of concrete over-pour. It is difficult (and hence quite expensive) to get the chemical into the trench evenly as it will want to run off to the bottom. If the footings are more than three quarters of a metre deep it is not only difficult to trench that far down beside the wall of a house it’s also very expensive to flood that much chemical to such a large volume of soil. Often the houses on a sloping site also have a rubble drain next to the wall. These areas cannot be chemically treated as the chemical immediately drains away down the slope and might cause environmental pollution.

All modern termiticides are biodegradable in contact with the soil. They break down over time. At present the best products are lasting as long as 10 years in the soil. Of course the period of time they last is affected by many variables. The actual life of the chemical and its ongoing effectiveness after several years can only be determined with sophisticated scientific equipment. Consequently it is difficult to know when the chemical treated zone is due for renewal. Our advice would be to always err on the side of caution. Even though some salespeople will suggest to you or imply that the chemical treatment you are purchasing will last for 10 years or more it may in fact need renewing at the 3 to 5 year mark. Be very careful of companies that offer 10 or 20 year warranties on their chemical treated zones. Not only will this lull you into a false sense of security but you may find that the warranties are not honoured for one reason or another and you will end up wearing the costs of termite damage to your home.

When a treated zone is installed some thought should go into how it will be renewed in 3 to 5 years time. A reticulation system will certainly add to the initial cost but it will greatly reduce the price to renew the chemical in the soil when it needs topping up.

However, if a reticulation system fails during the recharge, it’s very hard to detect simply because it is buried in the soil. Should it fail along a section of 3 metres or more then it may leave a sizeable gap in the treated zone which could allow termites ready access to the home.

If reticulation is not installed, then the homeowner will have to undergo another very similar disruption to their lawns, gardens, paving and concrete when the treated zone is due for renewal. It’s also likely to cost a similar amount usually in the $3500 – $5000 range for a quality application in accord with the Australian Standards.

The Green Termite Baiting System 

Okay, we will now discuss the pros and cons of the Green Termite Baiting System. We would like to point out that we are not going to discuss ‘termite baiting systems’ in general because there are many termite baiting systems that have endemic weaknesses which are not inherent in the Green Termite Baiting System. If you wish to compare termite baiting systems we have a dedicated page on our website that specifically covers that topic here.

The original Green Termite Baiting System began in 1996. It has undergone several improvements in the past 13 years but the basic principle behind it remains the same. A principal which has proven to be a sound method which lures termites so that they can be easily and effectively treated with an undetectable transferable termiticide which is returned to the nest by the workers which in turn leads to the destruction of the colony. Whew… there you go, the whole system in one sentence!

The Green Termite Baiting System is based on the well-known KISS principle. They are very easy to install, easy to check and easy to treat when they become active with termites. There are no moving parts to become jammed, no cavities that can become filled with regular garden ants which are repellent to termites and there is minimal disturbance during the treatment phase which ensures the maximum effectiveness when a suitable termiticide dust (Termidor® or Intrigue®) is applied. Over the past 12 years, the success rate of the Green Termite Baiting System at preventing new colonies of termites from damaging homes remains at well over 99%. This is based on immaculately kept statistics for hundreds of ‘full service’ customers in S.E. Qld.

It is important to remember that the Green Termite Baiting System is designed to prevent termite colonies located outside the home from gaining entrance into the home undetected. They are not designed to treat existing termites inside the home. Termites that are already inside the home need to be treated first by a professional. Once the problem is successfully resolved, then it is advisable to add a Green Termite Baiting System to reduce the risk of further problems later on.

Termite baits need to be checked at least once a month. The disadvantage of this is that it creates an ongoing expense. After five years a bait system may cost as much as (or even more than) a chemical treated zone. However, a chemical treated zone will need renewing; usually at considerable expense and inconvenience if a reticulation system wasn’t installed, whereas a termite baiting system maintains continuous high-level protection at a reasonably affordable month-to-month price.

Proponents of treated zones or should we say opponents of baiting systems will often say that the weakness of the baiting system is that termites may go between the baits and get into the house. Of course this is possible if the baits are placed too far apart. However, when the termite baits are correctly placed at 2 to 3 m intervals it is extremely rare for scouting termites to miss them. In fact, scouting termites are very good at finding timber in the ground. Lucky for them since they depend on this well honed skill for their survival! Termite scouts are underground experts at finding food. Finding a well-positioned termite bait is a piece of cake for them.

To reiterate; when they do find a Green Termite Bait it is a simple matter of treating the bait without disturbing the termites so that the workers relocate an appropriate termiticide back to the nest which results in the destruction of the colony.

Concrete can present a problem for the placement of termite baits however not as big a problem as one would think. Firstly, it is often quite easy to skirt the baits around the edge of the concrete. This extra distance might use up a few extra baits but termites will still need to go within range of the baits if they are to make it to the house. Another good reason for placing baits beside pathways is that termites normally travel in the top few inches of soil. Consequently, they are likely to bump against the edge of the path below ground level and the natural tendency will then be to follow along the edge of the pathway looking for a way past. If they reach an expansion joint the termites can follow through it until they reach the wall of the house. Sometimes this form of entry gives them a direct access route across and above a chemical treated zone. When installing Green Termite Baits we always recommend to position the baits beside the expansion joints in concrete paths, patios etc.

There are some exceptions where the expanse of concrete is simply too great or where the concrete extends from the wall of the house to the boundary fence. In this case the concrete needs to be core-cut to allow the insertion of a termite bait. No doubt this does add an extra one-off expense to the installation but it is certainly still a great deal cheaper than the alternative of cutting the concrete along the whole perimeter to allow for a chemical treated zone to be installed.

In summary: Both termite protection systems offer excellent protection when installed and maintained correctly. Sometimes one method is the obvious choice over the other. Sometimes a combination of both methods is the best solution. They each have their features and anyone considering long-term termite protection for their home should weigh up the pros and cons of both before choosing one over the other. If you still can’t decide, we recommend that you consult with a professional termite company and have them clearly explain why your home is more suited to one system than the other. Of course, if you get two or three quotes you may find conflicting points of view. Be careful of companies that only offer one choice because that is no choice at all. Hopefully this article will arm you with the right knowledge to help you to decide which system is best suited for your particular home.