Increasing energy efficiency to 7 stars for new dwellings

We recently posted a question to LinkedIn groups and setup a poll on twitter. The question was “Who would like to see the Building Code of Australia (BCA) increase energy efficiency to 7 stars for new dwellings?”

We have received some interesting responses and dialogue. Here are some of them: [the posters will remain anonymous]

1. not me. prescriptive design controls are adding dramatically to the cost of construction. there is no substitute for quality, passive design.

2. In theory, Yes. In reality, No. In between, tread with caution. I’ve seen projects easily hit 9-10 stars, whilst I’ve also seen others struggle to get 3-4 stars. I think the rating system is fine as a yard stick, but is still rudimentary, so getting too accurate with it could become a double-edged sword. We are dealing with a system which is based on assumptions, which is why it cannot be applied to Class 3. I, for one, am not comfortable with the current system for accuracy because it assumes that everyone lives in “ideal” world where everyone gets up at the same time, leaves the bedroom and enters the living area at the same time, leaves the house at the same time, comes home at the same time, cooks at the same time, using the same oven settings at the same time, watches TV in the living room (not the bedroom) at the same time, and then finally goes to bed at the same time. Ironically, they can shower, shave and ‘other’ any time of day without any impact. This does not account for families with small children and stay-at-home mums, or shift workers, or SOHO (Sole Operator Home Office) people, or retirees, who could need to sleep in an eastern facing bedroom at 10am in summer with full sun, etc. The model is sound, but fundamentally rudimentary, so trying to get too accurate with it is like asking a747 to land on one of those quaint English country lanes! I commend and admonish Victoria at once for touting the idea of going back to 5 stars, because it is a rudimentary system, but we must continue to improve efficiency. The answer is not in the rating, but in the application of lessons learnt by those involved to create genuinely energy-efficient designs regardless of rating systems. And this comes from desire, exposure and application; not rating systems.

3. In the age of the project builder, design for climate & design for the site seems to be a long forgotten principle of building. I have the occassional client who will ask – “why do I need an energy assessment done – I am putting in an air conditioner”.

4. I believe we are all reaching for the stars – and heading towards all new builds being 10 star rating in the next 3 years (2015?)

5. I am all for it, all our current projects have hit 7-8 stars without many issues and the clients are loving it. We changed our way of thinking and doing things and it has paid off with more enquires and sign ups than ever before. Let’s face it is not hard to get 7 or 8 stars and the client is getting a much more comfortable home and should not need that A/C or gas heater as well as they are using less power to light up the rooms. Prime answer is a client of ours who lives on the coast that gets very cold in winter and also very hot in summer only uses his A/C for the last year a total of 6hrs. I was at his house the other day and it was 2 degs and I was rugged up like no tomorrow and he was walking around in shorts and a tee shirt and the A/C had been on for 1/2hr to take the chill off. Yes it has taken a few more dollars but when explained t the client they jumped on board and they are extremely happy now that they did. The only hurdle that does not help 7 stars to come in is client’s pockets, in a market that is slow at the moment for some builders if this came in I think a lot more builders will be shutting their doors. So do it but do it when the industry is back on the rise otherwise it will make a lot of families very upset, this being the client as they are now not sure if it is right to spend that extra $10 or $20k and then that poor builder who has been around for many years and has to shut his doors because he has no work.

6. The NCC (previously BCA) is moving in this direction, and there is a DCCEE commissioned report prepared by Pitt & Sherry that investigates the cost implcations of increased stringency. Pathway to 2020 for Increased Stringency in New Building Energy Efficiency Standards: Benefit Cost Analysis FINAL REPORT Prepared for: Department of Climate Change and Energy Efficiency Ref: DCCEE 867/2010. Moving to 7 stars as mandatory efficiency for houses is a reasonably cost effective move and can be accomplished with passive design changes. It should result in more individual designs that are done to suit location and aspect. There will be a push by the large building companies to stop this from happening as the build costs increase hence their margins decrease, and the individuality of houses has to be taken into account to suit the topography. This also makes it a bit harder to do the 20 house in an estate that are basically all the same. One issue is the indoor evironment quality of houses may decrease due the the increased stringency resulting in decreased glass and daylight penetration, as well as reduced access to views. The “cookie cutter” approach means houses will be designed for the worst case orientation and not be adjusted to suit the topography or building orientation. It is a difficult balance because we are in danger of focusing on just the energy efficiency, and not the livability of houses, will we end up with highly efficienct house that drive us all insane? Using the energy efficiency and air-conditioned approach the best house to live in is a cave underground, and a mix of fans, light tubes and air-conditioning to make it reasonable to live in, check out the houses in Coober Pedy. But would we all like to live in that style of dwelling?

7. Responding to number 6 above – Some nice thoughts. Some of what you say expands on my last comment (above). The designers have to take all aspects into the design, and preferably using passive design techniques, so that the IEQ is not compromised (or any other concern, such as affordability, etc). I can still see a place for the builders who want to sell several houses off one plan, but instead of selling them all on the same estate, they will need to start looking on a different plane and selling them on the same orientation. So, Floor Plan A is a northern facing home on a southern slope, Floor Plan B is an eastern facing home on flat land, etc. With many larger builders now developing multiple sites, this should be feasible, and will drive the industry in which the smaller players will adapt (as they always do with change). I think if we are going to drive higher and higher in energy efficiency, then we are going to have to change the rating system to remove some of the assumptions to allow for all possible combinations of occupant usage. NatHERS is simple and cheap, but it is not accurate. Perhaps the next generation of rating tools will be able to overcome the limitations based on what industry has learnt in the preceding years. Also, if the ratings get too hard, then people will just revert to DTS as it becomes the lesser of two evils again.

8. Responding to number 7 above – Agreed. With all your comments. Using NatHERS and the other simple programs avaiable don’t allow for individual assessment. I use IES-VE for commercial projects but it is just as easy to use for residential and it allows full optimization. You input all the profiles for use of the buildings, and you can assess these against a standard set or profiles to see what the impacts are. You also get a full energy and green house gas appraisal of each building instead of a star rating. This would allow you to use standard designs and minor adjustment to suit site and other conditions.

9. Responding to number 8 above – That’s right. I’ve also used TAS, as well as IES. Of course, there are others of the same ilk, but alas their price makes them prohibitive. Also, their level of customisation makes them double-edged swords for inexperienced modelers. Then there are others, such as Beaver, Design Builder, etc which are much cheaper, but less versatile. You’re touching on the core of the future when you mention GHG appraisal as opposed to Star Ratings (or Drop Ratings, or Leaf Ratings, or any other dissociated symbol that has connotations of something environmentally ethical). Ultimately, we will have to go back to basics and rely on well-experienced professionals to get the design right to start with, before relying on a computer program to confirm what we already know. (I fear there are too many modelers out there who don’t really fully understand what they are doing, and hence producing erroneous results which they truly believe in.)

10. I agree get the design right – design for sustainability with energy efficient materials. We regularly achieve 8 stars (minimum) and are heading for 9 – without the use of expensive “add on ” solutions. Apart from the regimes used to measure and assess – the RIGHT materials must be used to achieve desired level of performance with out pushing the price point beyond the wider market.I must declare biased to using “insulated structural panels ” even as cladding medium & be integrated into contemporary design today – no need to wait for tomorrow.

11. I think the issue is bringing the existing stock of housing to reasonable energy efficiency. Let’s get everything to six stars before we think about seven.

12. At the risk of sounding bureaucratic sustainability ratings for dwellings should be assessed under the Planning Scheme (where applicable) and not prescribed by just the BCA. It’s at the planning phase of a project that most sustainability benefits can be gained with respect to building orientation and passive solar design. The best that the BCA can do is rate material selections / heat gains and losses through apertures and is therefore limited in its ability to prescribe higher sustainability ratings. At least not without major design changes – which puts you back to the planning phase. In real terms – the current process could significantly add to holding costs and professional fees – especially where a Planning Permit is required – by allowing the sustainability ratings assessment to be undertaken at the later phase of Building Code compliance.

13. I need to ask this question of you all and if it was possible I would love to direct this question to the people upgrading the BCA.
Q If the target is to reach a 7, 8, or 10 star rating on new builds, why not go across the board and force every dwelling that does not comply to say 5 or 6 star rating to catch up? There is no basis for either. Do you think there is an improvement in energy efficiencies and sustainability? Personally I believe so. There is no economic responsibility to local employment when suppliers quite easily now import from Asia and charge as much as the local goods. So sacrifice the local market and work force, increase bottom lines by purchasing overseas and get your 10 star rating. This is simply one aspect. And as for getting the design right let me go a step further, when planning subdivisions the block orientation should be the first consideration not how many lots can we get out of a subdivision. This would make designing a home a little simpler because you dont have to deal with the orientation. If th is so critical why not take away choice and provide one model that can increase in size without changing the variables and then it will always be right according to the codes. Why not do away with fencelines and build each house next to the other this will increase the thermal mass it may not look good but it is not about looking good it’s about achieving the “STAR RATING”. At some point someone is going to have to sit down and put a price on this and it can not be a ficticious value to the consumer. (Someone is bound to hit me with the environment dilemma here. I am all for the environment and doing the right thing. [TURN YOUR HIGH POWERED TELEVISIONS OFF. YOU WANT TO SEE SPORT GO AND WATCH THEM LIVE]. Perhaps this is to harsh of me. Band aid solutions, I am totally against. Fix the problem totally. Household technology is inefficient why not ban the import of or manufacturing of household goods that do not comply as part of the solution? Where is the BCA now? Here is one for the learn-ed. Update the education system so that it abolishes the old building technologies and only teaches the new technologies. Have refresher coarses where it is mandetory for us to go back and get re-educated. I can go on and on and on. Yes I am a builder, I build other people’s designs based on clients budgets. I dont build in the lower end markets because it is depressing when you see clients that want the Aussie dream home but cant quite make it. So now the BCA is to put another squeeze on.
Selfishness utter selfishness. This is not the Australia I know. The boffins writting policy need to wake up and get with the program.

14. I ask you all this. Do any of you have children at the age of 15 to 18? Consider which state you live in which town how much is real estate now. Now consider when your children reach 24 or 25 and want to consider buying a house. Will they be able to afford it? Now if your children are under 15 I will put it to you another way is your home big enough for your children to live in it when they are 24 or 25? Some may say, I havent got a clue about what I am saying. For that say that do not have a heart for the low social order because they are not in that order.
The reality is it is unsustainable for us to continue this way. Is rent affordable in the city you live in?

15. Just a comment on the use of imported products and doing it cheaply out of China, I have worked on a couple China based projects with China based project teams, and have found that Chinese contractors do not have the same level of compliance for sustainable design, even when it is a target on a project. Product out of China is generally not certified to meet Australian Standards and in most cases does not meet the test requirements, particularly for fire rating and thermal performance of prefabricated items, unless the contractor is very, very careful and does a large amount of quality assurance in China during the construction process the products do not gerenally match the specifications for the project. On the projects I have worked on this has resulted in increased costs to the builder, above normal due to the rework required.
Substitution of product with alternative untested product does occur, even the company stamp is replicated and when investigated with the actual product supplier it has been found they did not supply the product to the project it is a copy. On your other point on the costs of housing, the long term costs associated with using the inferior products is unknown, but if you consider the economic costs to society of Asbestos, you will have to agree that the regulation will benefit our children in the future. I have children under 10 and the best way I know of making sure they can afford a home in the future is for them to have one that has very low running costs, as you will find that in the future, as now, that running costs will be the main driver of the cost of home ownership, not the initial capital cost. Increasing regulation and stringency that we need now is for the future of our children to ensure they can afford to own a home. Innovation, new products better building technologies, more efficiency in manufacturing and construction, these are all the outcomes of the increased requirements. We have the opportunity to innovate and get better at what we do, if fact we need to do it all better to reduce costs, that is the real outcome of the drive of the BCA, that is where the BCA is at now.

On the twitter poll: 54% of respondants said they would like to see the BCA increase to 7 stars. 23% said no. 23% said they would to see it increased to 8 stars.

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