Presentation: Energy Efficiency Case Studies, Class 2-9
On Saturday 11th of May 2013, Dr Clyde Anderson gave a technical presentation to the Australian Institute of Building Surveyors at their annual conference. Many topics were covered in this presentation and we will be expanding them into full articles in the future. Here’s a quick summary.
What is a competent person?
A brief survey of the audience revealed that every Building Surveyor present had seen at least one “junk” Energy Efficiency Report – one that was either unsatisfactory, inaccurate or just plain wrong. When confirming the abilities of an Energy Efficiency Assessor, you should check the following: Do they have a good reputation, are they known to be “tough” occasionally, do they abide by a code of conduct, do they have adequate experience, do they have adequate education that has been tested, do they participate in a CPD program, do they have a Quality Management System, and do they have Professional Indemnity Insurance?
Roof Energy vs Solar Absorptance
We have been researching the effects of Solar Absorptance on the amount of heat transferred through roofs. The results highly vary per building and is too much to summarise in a single paragraph, but there was a clear trend that an uninsulated concrete roof has less variance than an uninsulated metal roof. We also noticed there is little difference between an insulated concrete & an insulated metal roof.
Wall Energy vs Solar Absorptance
We also researched the effects of Solar Absorptance and the amount of heat transferred through the walls. These results are also too numerous to summarise in one paragraph but we noticed that for insulated walls there is little difference between FC Panel and Concrete Panel walls. We also noticed that for a maximum benefit, wall insulation is needed for hot & cold climates but less insulation is better for temperate warm/cool climates.
Floor Energy vs Solar Absorptance
Completing our research on the effects of Solar Absorptance, we investigated its effects on the amount of heat transferred through a suspended floor. This one’s results are surprising – the Solar Absorptance value did impact the heat transfer! This is likely due to the 20% ground reflection of sunlight and these results need more investigation before we can confirm them. However, we can say that for insulated floors there is little difference between Timber or Suspended Concrete. Also, no floor insulation is needed in hot or warm climates, but some insulation is beneficial for cold climates.
Roof Insulation Compression
Compression of roof insulation by any means – to fit into a tight space, underneath purlins or even by a safety mesh – compromises its performance. Calculating this decrease in R-value is difficult, which is why we have released a calculator to crunch the numbers for you. This calculator is as accurate as we could make it (regression coefficient of at least 0.9992). Best of all, it’s free! We are providing this as a service to the whole industry. Check it out.
If you’re interested in an Energy Efficiency Rating performed by someone who knows the material so well they can teach others, contact us for a competitive fee proposal. We deal in both Residential and Commercial work throughout Australia, from tiny 1-room house extensions to entire office complexes.