Submission by the Australian Institute of Architects (NT) in response to
Review of the National Construction Code (NCC) -
Energy Efficiency
Department of Lands, Planning and Environment
Northern Territory Government
December 2015
Australian Institute of Architects
December 2015
SUBMISSION BY
Australian Institute of Architects - NT Chapter
The Royal Australian Institute of Architects trading as Australian Institute of Architects
ABN 72 000 023 012
Unit 3, 4 Shepherd Street
DARWIN NT 0800
GPO Box 1017
DARWIN NT 0801 Australia
T +61 8 8936 1820
E nt@architecture.com.au
PURPOSE
This submission is made by the Northern Territory Chapter of the Australian
Institute of Architects (the Institute) to the Domestic Building Code
Review Group, Northern Territory Department of Lands Planning and the
Environment, in response to the invitation for Community Submissions,
November 2015: http://www.lands.nt.gov.au/building/energy#submissions
At the time of the submission the office bearers of the Northern Territory
Chapter are Simon Scally (President), Richard Layton (Past President),
Andrew Broffman, Alice Chambers, Ross Connolly, Jenny Culgan, Robert
Foote, Steve Huntingford, Rossi Kourounis, Tammy Neumann, Katy Moir,
Joshua Bellette, Jurse Salandanan. The Chapter Manager of the Northern
Territory Chapter is Joshua Morrin.
This submission was prepared by Joshua Morrin, NT & International Chapter
Manager, with the assistance of Jo Best and Simon Scally, for the Northern
Territory Chapter Council.
ABOUT THE INSTITUTE
The Australian Institute of Architects, incorporated in 1929, is one of the 96 member associations of the International Union of Architects (UIA) and is represented on the International Practice Commission. The Institute is an independent voluntary subscription-based professional member organisation with more than 12,000 members who are bound by a Code of Conduct and
Disciplinary Procedures. The Institute is the peak body for the architectural profession in Australia, and works to improve our built environment by promoting quality, responsible, sustainable design.
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Preamble
It seems a standard assumption that a resident of a hot or tropical climate be a devotee of air conditioning – so much so that at almost no point does anyone seem to stop and ask whether our supposed reliance on air conditioning is in fact well founded, when human beings seem to have been able to live in such parts of the world for many thousands of years without it.
This is not to be mistaken as a criticism of air conditioning – most of use and enjoy air conditioned spaces for many purposes – but what seems to be in place is the assumption that, in terms of the buildings in which we live and work, it will be required . In effect, this assumption seems now so ingrained that choice has been removed from the consumer, such that it is now overly difficult, within the existing regulatory framework, to procure and build a naturally ventilated dwelling, which takes advantage of whatever natural breeze might prevail. This is illiberal, and cannot be good for the consumer.
The purpose of this submission is therefore to provide comment and recommendation to the Review Group, on behalf of the Australian Institute of
Architects, with respect to the scope and direction of their work.
The Institute, whilst representing more than 12,000 members, has a fundamental commitment to issues of design quality and amenity within our built environment, and the promotion of policies that make for sustainable communities. Whilst in the commercial reality of the housing market architects may provide little direct service, we believe that there are fundamental design principles which can be implemented for the overall improvement of housing stock, which will be of benefit to everyone and provide Territorians with better places in which to live.
1. Climatically Responsive vs Energy Efficient
The Terms of the Review as presently structured appear to draw a distinction between energy efficiency and climatic responsiveness. Energy Efficiency, as we understand it, measures the level of efficiency of a dwelling in relation to its overall usage of energy for purposes of controlling climate, particularly with respect to applied technologies (whether for heating or cooling). By way of contrast, climatically responsive housing we understand to be designed in such a way as to obviate the need for devices for climate control – if not altogether, then at least to reduce the overall need for them. Put simply, the difference is that the one (“energy efficient” design) seeks to ensure the efficient use of energy inputs, whereas the other (“climatically responsive” design) seeks to reduce the need for energy inputs altogether. We argue that the latter, when executed appropriately, comes at comparatively less cost to the owner (in terms of energy use), and so less cost to government (in terms of demand on infrastructure). In our view this represents a sounder basis for the development of housing responses.
Furthermore, our view is that there is limited equivalence between energy efficiency and climatic responsiveness, and in fact that emphasis on the one may well lead to the exclusion of the other. Certainly in working practice we are aware of numerous instances where a house that is designed according to passive design principles, which uses less energy overall in terms of daily patterns as well as lifecycle, scores less well according to existing energy ratings assessment than would its counterpart. The attached example (refer
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Appendix) illustrates two designs for the same site, which score markedly differently on the same energy assessment index, but in which the “energy efficient” option (8.2 stars, out of a possible 10) would seem to seem to be preferred over the “climatically responsive” (5 stars) – albeit at a higher energy cost to maintain. Such a situation is logical, but short-sighted.
In general terms, climatically responsive housing ought to be designed in such a way that it is inherently energy efficient, whereas housing that has the objective of achieving energy efficiency will not necessarily result in a climatically appropriate response. We therefore recommend that in considering any proposed changes to the existing framework, the Review
Group place an emphasis on climatically responsive housing, over and above energy efficiency measures.
2. Climatically Responsive Housing
We note from the survey provided a number of questions pertaining to
Climatically Responsive Housing which address understandings of meaning and appearance. We wish to make the point that climatically responsive design is not primarily a question of aesthetics, but of performance. Housing designs that place an emphasis on performance will, in the hands of a range of designers, result in a variety of forms of expression, each of which commence at the same point of origin. We would support, in principle, the development of design guidelines to meet this objective. We also understand that the Group may be considering the registration of building designers and/ or the demonstration of a minimum understanding of appropriate climatic design by anyone who designs a home. Again, we offer our in principle support to this investigation.
In addition, we note that attempts to quantify the conditions under which users find an environment comfortable can be fraught, and relate to a large number of variables. There is a significant amount of research that has been undertaken to identify the range within which comfort is felt, on a regionallyspecific basis. By way of example, we refer the Review Group to the regionally specific work of COOLmob. We suggest that with more data logging for tropical environments, energy rating tools can be better informed. The same can be said for the range of climatic conditions encountered throughout the land area of the Northern Territory, including for example the arid environment of Alice Springs.
3. Affordability
The majority of current metrics with respect to affordability place an emphasis on the upfront cost of investment, whereas the true cost relates to the lifecycle of the building. By this measure, we believe that climatically responsive housing will provide greater savings to users, in terms of energy cost over the lifetime of the building, that offset any potential upfront cost difference between dwellings that are designed solely in terms of “energy efficient” principles. This applies not only to the formal design, but equally to choice of materials and systems of construction that establish the building envelope. We also make the point that if affordability is the objective, then the question relates less to aesthetics than it does to performance. It is exceptionally difficult to design a cheap tropical house that looks the same as
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December 2015 a “southern” house, which at the same time seeks to function in a way that reduces the need for energy.
In addition, on the measure of affordability there are a number of possible avenues which might provide for substantial savings. Bernard Salt has recently commented, in relation to the nature of the Australian house, that
“Australia’s prosperity from the 1990s onwards and new ways of living with fewer but more indulged children reshaped the family home. Houses now needed two bathrooms as well as separate space for kids and parents. The family room begat the home theatre and the formal rooms at the front of the house diminished” such that “the house expands to accommodate the interests and the private-space aspirations of generally fewer family members”
(Bernard Salt, “From Manchester to Milan: how our houses evolved for climate and prestige”, The Australian, November 26, 2015, p. 28).
An easy strategy to address affordability would therefore be to build smaller houses, which relate to the smaller family unit sizes now occupying them.
Smaller footprints will require fundamentally less energy to maintain than larger footprints; they can be developed on smaller lots; and with smaller lots accommodate larger numbers of dwellings in closer proximity to central jobs and services. Smaller footprints can also be more easily designed to permit tropically-appropriate passive design principles, such as narrow-aspect floorplates to facilitate cross-ventilation.
4. Energy Efficiency Provisions and Passive Design Principles
The current provisions within the BCA for reducing greenhouse gases have focused on the building envelope, and the primary means of assessment via rating tools limited to what defines the envelope, rather than good and appropriate design for the specific climatic character of the building location.
The notion of sustainability in housing is a broader issue that needs to consider the amount of energy use as well as the minimisation of energy loss, both at the time of construction, and for the lifetime of a building.
While we acknowledge advances in some ratings programs to include calculations of a wider set of climatic date, there remains a lack of recognition within the system for the rating of houses that have minimal or no mechanical conditioning, the very houses that use the least amount of energy. There is also a lack of consideration of behavioural acceptance for seasonal change.
Houses designed with an appropriate response to the climate have the ability to reduce the necessity of year round mechanical conditioning and thus also reduce energy use.
In 2008, the Institute prepared the following submission to the then
Infrastructure Sustainability Unit, within the Department of Planning and
Infrastructure. The following excerpts provide a summary of our view:
Recent changes to the Building Code of Australia have incorporated energy savings provisions. There is now a move towards the use of energy rating software to assess and rate the energy efficiency of buildings. Although there has been a great deal of work done on various software programs in an attempt to analyse house conditions and predict energy use in houses, we believe there is a fundamental error in the approach of these programs,
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December 2015 in particular for tropical regions. The programs make the assumption that buildings will be air conditioned and focus on reducing the energy consumption of the air conditioners. We believe a better approach would be to focus on reducing the need for and reliance on year round air conditioning via the use of passive design principles.
Passive design principles for building design in tropical regions are well documented and include, shading of walls and windows, maximizing cross ventilation, orientation of the plan, steep pitched ventilated roofs, light roof colours, roof insulation, etc.
Forty years ago the Commonwealth Housing Commission provided Darwin with a great legacy of simple cheap housing that performs exceptionally well in our tropical conditions, which are still sought after and forms the bulk of housing around the older suburbs of Stuart Park, Parap, Fannie Bay and
Nightcliff.
Energy provisions have been added to the BCA in recent years. The regulations generally are reasonable initiatives (shading of walls, light coloured roofs and addition of insulation where required to reduce heat load) with the exception of those parts that assume air conditioned environments and hence limit glass areas and require sealing of rooms. This can and does lead to situations where cross flow ventilation is minimised, providing less opportunity for a house to be naturally ventilated.
It is vital that Housing be assessed in terms of its real energy use in order to cut emissions. If comparisons are to be made they should be undertaken on a performance assessment of a particular house, over time, based on the number of people living in the house. This rating will be a dynamic thing and can and should change over time.
We continue to recommend that there is room for improvement in the terms and mechanisms of the rating system. We would like to see a reversal of the focus on the efficient energy usage of climate control systems, to an emphasis on passive design principles. This could be achieved, we believe, by clarifications within the existing system. We believe this would be by far the best mechanism for reduction of greenhouse gas emissions within the domestic housing market.
Individual energy production should also be recognized when determining the performance of specific houses, as well as the beneficial contribution thoughtful landscaping and ground treatments can provide. It is well established, for example, that domestic solar panels can harvest sufficient energy for not only the house, but a surplus which can be fed into the local grid. The Institute would welcome improvements to the current system which recognise, and potentially even incentivise, the contributions that such incorporations can provide.
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5. Cultural Character
We would welcome the Review considering approaches that consolidate the unique aspects of the well-established Territory lifestyle, rather than mimic approaches from elsewhere in Australia. Recent housing development in the Northern Territory, particularly in the Top End, has in many cases only contributed to the ‘relocated from other climatic regions’ housing types and the notion that there is a loss of the tropical character previously associated with this part of the country. Appropriate urban design in response to location, taking into account block size, orientation, and climatic data is essential in the successful delivery of housing in the Northern Territory, and can only assist in the performance of individual dwellings as well as improve the amenity of the region, be it an inner city suburb or remote dwelling.
6. Administration of Building Regulations
In response to the first question of this category of the survey, we see no reason why the National Construction Code should not apply equally throughout the Northern Territory. The NCC provides important health and safety standards for housing and should be applied across all regions to ensure safety of occupants. The process for applying the NCC standards could be simplified to reduce administrative costs. We also suggest that the Review Group consider mechanisms for dispensation in scenarios where there may not be the infrastructure in place to support the current energy efficiency requirements, but buildings are still required to meet NCC ratings. This is frequently the case in Government funded housing in remote communities.
We support the Review Group in considering the processes currently available for Energy Assessment of proposed developments. The current system raises numerous questions, including:
• the registration requirements of energy assessors
• the time committed to assessment
• processes for review of the rating, to ensure the information used is the same as the drawing set issued for permit and construction
• the dearth of inspections during construction, to ensure materials and workmanship meet the specifications of the drawings and manufacturers’ installation guidelines.
7. Other recommendations
In closing, we suggest that the work of the Review Group might also be informed by the following:
1. Increased education on how to improve energy efficiency in existing houses.
2. Providing education to the public on good house design, and what to look for when buying a house in order to reduce energy use, in particular air conditioning.
3. Government funding for projects which lead by example utilizing passive design principles.
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4. Regulating fundamental design elements, to be incorporated into all new housing, such as:
• Minimum roof overhangs (taking into account aspect)
• Minimum openable window areas to all habitable rooms
• Roof space ventilation where spaces are non air-conditioned
• Roof colour
5. Developing systems that support design options that are un/zoned A/C to offer the lowest possible energy use buildings. In the case of Government funded projects, this might be further supported by a needs-based assessment of tenant groups, to ensure that housing designs provide a model of affordability that relates to the financial means of the intended tenants. It is unreasonable to provide houses where tenants cannot afford to pay the energy bills.
We look forward to receiving feedback from the Group in relation to its discussion and potential alterations to the current energy rating tools for distribution to our members.
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APPENDIX
Comparative energy assessment of two proposed dwellings for the same site (2013)
Australian Institute of Architects
December 2015
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