Dr Don builds on a few points from his FAOPMA talk


There’s been a lot of ill-informed speculation about how pre-construction soil chemicals are affected after the Building Code’s grace period. The grace period, which allows reference to the year 2000 versions of the termite management Standards AS 3660.1 & AS 3660.3, ends after April 2017. The problems are not so much with the wording of the Standard, the features & faults of which we’ve known about for several years, but the way the ABCB have then called this document into the Building Code of Australia [1] (BCA). 

The changes to the Standards were signed-off by AEPMA who have two representatives on the drafting committee. 

There are several issues. The oldest one is that you may not interfere with the builder’s plastic membrane around slabs and footings. This means that you cannot apply an exterior soil chemical (spray or reticulation) at construction where the plastic is in place.

Next is that from the first of May 2017, the BCA wording requires that all products have passed the testing of AS 3660.3–2014 - the older version won’t do. For the ABCB, an APVMA label is no longer enough. They (you) need proof of the performance. So, yes, potentially this does mean a (temporary [2] ) end to pre-con chemical use, which includes the chemical sheet material as well. Perhaps this is really a good thing and the industry can move forward to better options?

Another issue is that products and systems are in use which rely on CodeMarkTM certification to meet the BCA need, and don’t claim any conformity with AS 3660.1-2014. As most of you have insurance and contracts that routinely require compliance with Australian Standards, now is a good time to (a) obtain appropriate insurance cover and (b) obtain appropriate wording to use with the systems, either from the supplier or your insurer. This issue is present, for example, with some sheet and paint-on products and with Dow’s new baits.

Dow’s new baits can be used to get a builder out of a hole. AS 3660.3 has been written to include every possibility of a system to meet 3660.1, just as long as that system provides an inspection zone. Baits don’t meet this need. The baits can be used because their CodeMark certificate says that they meet the BCA’s Performance Requirements. Just follow the certificate. Also make sure that your insurance covers this endeavour and perhaps explore the value of having your lawyer draw up a covering agreement for the builder. Please be sure to follow the certificate’s 2016 version of the Technical Manual and not the 2015 one. Those relying on the first released version might not know when to use their “professional judgment (sic) of the site risks and local termite knowledge to determine actual monitoring frequency” which otherwise are, in some circumstances, specified as often as every fortnight. 

Making sure that you use the manual specified on the current CodeMark certificate is important for compliance. System manufacturers often come up with new installation details to cope with new construction details, but check that they’re in the version of the manual that’s listed on the current CodeMark certificate.

The Standards Committee wanted to apply a 50 year design life to all systems. The strong argument was that all currently available systems are used in Queensland where this is already required. The ABCB declined to accept the concept and the only bit of wording that survived the ABCB demands for change is in Clause 7.1.1. This basically says that for sub-slab and inaccessible areas, you can’t rely on a single chemical spray but, if spraying the soil and unable to get back to spray it again, you must provide reticulation to replenish it later. Or, like most of the nation, you could just use collars and a decent slab.

On the collar front, these now need to embed only 15 mm horizontally (but more is probably better). That’s fine, but the old wrap-the-sheet-around-the-pipe-and-hope method is no longer supported. Similarly, the installation of sheet is tightened a bit and closes out some of the issues where joints effectively rely on ongoing surface repellency.

At FAOPMA, some people got into a bit of a lather about what has to go into certification of installations. Now the ABCB made us take out the durable notice specification because this is already in the BCA. Similarly, the Standard couldn’t really contain mandatory reporting details beyond what the BCA has since to them it is just a builder’s recipe book. The reporting specification was agreed to become just guidelines. They appear referenced to a note (notes are not shall-do instructions) and are given in Appendix A2 which is labelled “informative” and not “mandatory”, so that’s pretty clear. The main worry was about clause A2 (k), which provides the opportunity to comment on some faults commonly found with suspended floor construction: clearances, ponding, drainage and ventilation. Where a construction has ‘features’ that include increased risk, you might make good use of the opportunity to diplomatically point this out. In general, you would not comment unless there is a clear duty of care you need to cover. Speak with your insurer about how to use the phrases, “Whilst not a builder . . .” and “Seek builder’s advice”.

The industry hasn’t got a great record of actually complying with AS 3660.1. Especially as many still refer to “Part A” and “Part B” sprays (gone in AS 3660–1993) and, have happily signed off on the incredible requirement for the pre-slab spray to deliver a 50 mm horizontal penetration into the vertical face of the trench. As far as we know, nobody has been caught for falsely claiming to have achieved that one, but it doesn’t quite have the same canine testicular observability as the issues mentioned above. 

[1]   Volumes 1 & 2 of the National Construction Code
Why ‘temporary’? Testing takes time. AS3660.3-2014 specifies “Replenishable chemical termite management systems require bioassays of at least 27 months, representing two calendar years plus one climatic season. Systems with non-replenishable chemical termite management systems such as concealed soil applications, treated sheets, extrusions and moulded and shaped components shall be proven in the field for not less than 36 months”.


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