We recently took the opportunity to have a chat with NatHERS subject matter expert Matthew Graham.
Matthew shares his insights around the best way for Assessors to learn and maintain their skills and knowledge and some of the top modelling issues for Assessors.
Let’s start with an introduction…
My name is Matthew Graham, and I’m the Principal of Graham Energy. We specialise in building thermal performance for medium to high-end projects. Over ten years,I’ve become recognised as a subject matter expert in the National House Energy Rating Scheme. I’m an ABSA and BDAV accredited Assessor in all three NatHERS software tools; AccuRate, BERS Pro and FirstRate5, a trainer in the Certificate IV in NatHERS qualification, a recognised BDAV Mentor and currently sit on the NatHERS Technical Advisory Committee. I was also engaged by Sustainability Victoria as a Project Advisor to contribute to the development of FirstRate5, provide technical support to FirstRate5 users and co-authored the FirstRate5 and AccuRate user manuals.
So, what is the best way for an accredited Assessor to learn and improve their skills?
Mentoring is certainly one option because it is personal and one-on-one, however, participating in regular CPD is a minimum requirement for an accredited Assessor, so that would have to be at the top of my list. Engaging in CPD created, endorsed or promoted by an AAO or RTO can certainly help.
I’m proud to be an accredited member with both AAO’s and honoured to sit on their respective Technical Advisory Committees with fellow experienced peers. As a Trainer and Mentor, it allows me to more broadly share my knowledge and gain a deeper understanding of the industry.
Altenatively talk to other Assessors through word of mouth, forums or the NatHERS Assessor Network Facebook page. Keep in mind with these sources that whilst Assessors can learn and improve their skills through these channels, answers may not have been rigorously checked and approved in the same way that an AAO or RTO would have done.
Do you have a top modelling tip for us based on your experience?
I’m not sure I could narrow it down to one, but earlier in the year I consulted with both ABSA and the BDAV to derive a top ten list of common modelling errors. Surprisingly most of the issues at the top of the list were common between both AAO.
That sounds interesting. Could you share a few of the top ten issues?
Sure, how about we start at the bottom of the list.It would likely take considerable time to cover the theory, practice and understand the consequences for each issue, so, for now, we could focus on current practice.
Ok, so, let’s start at the bottom of the list.
Interestingly the top ten ended up with one more. I felt the issue sitting just outside the top ten was still important for Assessors. So, effectively in 11thplace and where I’ll start is floor coverings. Floor coverings are often missing or incorrect. The reasons for this include user modelling error, possibly unclear documentation that hasn’t been clarified, or the incorrect application of the NatHERS Technical Note defaults or provisions.
Modelling errors can vary depending on the various NatHERS software tools. For AccuRate, a unique floor construction must be created for each specified floor coverings. Potentially, the user could assign the incorrect floor construction with respective floor covering to an area, and without any visual feedback, it is difficult to check.
For BERS Pro, users must separately select the floor covering and with multiple floor coverings, the percentage between the two.
For FirstRate5, the recent introduction of a Floor Builder provides greater flexibility, but users still need to separately select the floor covering and in case of a custom floor, be aware of potentially doubling up on a floor covering.
What about unclear documentation – how does that contribute to modelling errors with floor coverings?
If the floor finishes are unclear or not specified on the drawing set, you have two options; check with the client or, apply the NatHERS Technical Note defaults or provisions. My preference is to seek further clarification with the client and if they are not forthcoming, then apply the defaults or provisions.
Do you think Assessors are familiar enough with NatHERS Technical Note floor covering defaults?
They should be because they have not changed; however, the fact that floor covering related issues sit outside the top ten tends to suggest otherwise. There are more complicated modelling scenarios that Assessors could struggle with but I didn’t think floor coverings would be one of them.
For those who may need a refresher, could you briefly run through the floor covering defaults?
No problem. Floor coverings are now referenced in NatHERS Technical Note (June 2019) under Clause 6.3. The clauses have changed over several revisions. Where no floor covering has been specified; garages have a concrete floor or no floor covering, wet areas and kitchens have ceramic tiles and all other areas have carpet with a rubber underlay.
That’s great. Thank you for your time today, and we look forward to discovering more of the top ten in future posts.
You are welcome and thank you for the opportunity. I would also like to add that defining the top ten would not be possible without the assistance of ABSA and the BDAV for which I’m grateful.