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Energy Efficiency Compliance VS Sustainability

Sustainable Development is best known by the phrase that “Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs”. While there has been many interpretations of what sustainable development is, this notion of “Sustainable Development” is one that has been applied by many businesses that attempt to identify themselves as making an environmental difference. The goal for these businesses should be, to not only provide shelter complying with the minimum regulations, but also recognise the broader environmental affects of the processes taken. Sustainability consultants such as EcoForm pride themselves in ensuring that each new residence or commercial project achieves at least an energy efficient standard that complies with the regulations demonstrated by the Australian Standards and Building Codes. The consulting actions that these consultants suggest based on the merits of each project. The determining factors that can influence the necessary actions is location, orientation, design and materials used. Sustainability consultants can also assist builders, architects and designers to go beyond compliance and ensure that the projects they build meet the definition of a Sustainable Development. Builders, Designers, Architects and the like can influence their clients to create something that can make a sustainable difference rather than just another building, or extension. By ensuring the above is well considered during the design stage this can be achieved at minimum cost. Greater knowledge and understanding about how to make adjustments and provisions to a project can make a difference to the clients ongoing costs in the long run. Here is a brief overview of each point that can make a difference to greater energy efficiency and sustainability. Location: Every individual makes a choice about where they would like to live and each location has its limitations and challenges. Understanding the climate zone of a given location where a proposed development is built can help determine the best design, construction method, materials used and orientation. As well as the broader climate zones there are also micro climates used in energy efficiency calculations, each with its own limitations and benefits. Orientation: Together with location, the orientation of the residence plays a critical role in the efforts for a building to comply with the BCA. The best orientation for a residence is to ensure that the Living is facing north and the bedroom are facing south. Also to note is the distance of the north facing areas from the boundary, so that overshadowing of neighbours does not restrict solar access. Design: Ensuring the Living spaces of your home face north may be well known but knowing this on its own will not guarantee a 6 Star residence. The other design principles that are to be considered is the amount of glass, particularly in the living areas along with the depth of eaves. There is a lot of weighting on the living area when designing a home, getting this right can make it easier to achieve a 6 Star residence. Too much glass and not enough eaves can make the living area hot, not enough glass and too many eaves can make the living room cold. Each climate zone will have its own results but the trend is generally the same. Materials Used: When planning the construction of a new residence, there will be an idea or schedule of construction materials required for that design. Some builders have a set schedule of materials considered in building their clients homes, while others have can have the freedom to choose what materials they would like to incorporate into their dream home. When good design principles are encouraged, the need for changing a material selection is reduced, or less costly. It is possible to build a 6-Star residence throughout Australia without having to compromise on budget as long as the first 3 points on achieving an energy efficient house are considered. If you would like more information on the above contact your sustainability consultant. About the author: David Barham holds a degree in Sustainable Development from Murdoch University and is a Sustainability Consultant for EcoForm.

Double Glazing Myths

The energy efficiency of a building is influenced by many different design aspects. Orientation, insulation, ventilation, shading, sealing and building size are all important, and all interact with each other. In the face of this complexity, double glazed windows are often touted as a key ingredient of energy efficient buildings. Double glazing salesmen weave stories about unbeatable thermal insulation and improved efficiency of heating and cooling systems with noise attenuation thrown in as an added bonus. In the face of relentless promotion of double glazed windows as the answer to all energy efficiency needs, it is little wonder that a number of myths have emerged. MYTH NUMBER ONE: Double Glazing is Required By The Building Code The Building Code of Australia contains requirements to ensure a reasonable level of energy efficiency and a fair proportion of these requirements relate to windows. Importantly though, the requirements relate to the performance and usage of the windows, not to the type or design.The Building Code may, therefore, require a specific window to meet or exceed specific performance levels, but does not dictate how that performance level must be achieved. There are a range of options available to window designers to change the performance of a window including window type, glazing thickness, glazing coatings, double glazing, framing materials and thermal breaks within the framing. MYTH NUMBER TWO: Double Glazing Gives Better Thermal Insulation Than Single Glazing The energy efficiency characteristics of Australian window systems are modelled to international standards and are publicly available on the Window Energy Rating Scheme (WERS) website www.wers.netWERS contains ratings of around 3,000 window systems and is the recognised source for energy efficiency characteristics of Australian window systems.The rate of non solar heat loss or gain through a window is measured on a whole-of-window basis (framing and glazing combined) and is measured by the U-value. A lower U-value indicates that the window has a greater resistance to heat flow and offers better insulation.A review of aluminium-framed window ratings available from the WERS website shows that although double glazed windows can have very low (better) U-values, there is a wide range of performance. When compared to aluminium-framed Altair Louvre Windows it is clear that many double glazed windows actually have higher (worse) U-values than some configurations of single-glazed Altair Louvre Windows. MYTH NUMBER THREE: Double Glazing Always Improves The Energy Efficiency Of A Building If a building was to be sealed up tightly and the air conditioning system run 24 hours per day and 7 days per week, then the better insulation of double glazed windows* might make this myth true. But its rare to find people who want to live like this. Given the choice, most people prefer to open their windows and doors and enjoy fresh, natural breezes and a connection to the world outside. At identical sizes, Altair Louvre Windows deliver significantly more cooling, natural ventilation than any double glazed window. With more cooling ventilation, there is less need to run airconditioning systems and an air conditioner that is rarely used will consume significantly less total energy than an airconditioner than runs at its maximum efficiency, but is seldom turned off.*While it is true that windows with lower (better) U-values will help improve the energy efficiency of a building, it is not true that double glazed windows always have lower (better) U-values than single glazed windows. (See Myth 2) MYTH NUMBER FOUR: Double Glazing Is More Environmentally Friendly Than Single Glazing While some (but not all) double glazed windows may improve the energy efficiency of a building, there are a number of other aspects of environmental friendliness where single glazed windows outperform double glazed windows:  1. Raw material usage and embodied energy.By definition, double glazed windows have two panes of glass so require more total glass to manufacture. The spacers that hold the two panes of glass apart also require raw materials that would not be used for single glazed windows. Larger quantities of energy are required to produce larger quantities of raw materials. 2. Transport efficiencies.Double glazed windows are heavier than single glazed windows. Specialised machinery is therefore often required to handle double glazed windows and more energy is required to transport double glazed windows from the window fabricator to the building site. Make an educated decision In some circumstances double glazed windows may be the best option to achieve energy efficiency but don’t accept the simplified sales pitch that double glazed windows will meet all your energy efficiency needs – be sure to consider all the other factors that contribute towards naturally comfortable buildings. Make an educated decision. Source: Breezeway – The Double Glazing Myths http://www.breezway.com.au/the-double-glazing-myths/

Considering Passive Design

Lots are getting smaller and the ability to design a house that incorporates passive design is becoming progressively difficult. It has been noted that there are several core factors in the design process that are to be considered, there is orientation, materialistic factors such as thermal mass, ventilation, insulation, shading and glazing to be well thought out. However the chosen lot to build on can make it hard for a designer or architect and will have to work with its given location and orientation. The appropriate attention provided to each of these factors can vary according to the location of a proposed building, for instance a building up north of Australia will require different attention to each of these factors compared building in a more southern climate. Effective materials for harnessing and distributing that solar energy is appropriate, such as the right window treatments, adequately insulated walls and ceilings, windows, and roofs and high thermal mass materials . Other factors to consider is ensuring that there are no draughts and that all external doors or windows are to be sealed. Orientation Starting from the appropriate floor plan, if possible, it is best to have a decent setback of at least 3m to the neighbouring residence from the East, North and West boundary to minimise the possibility of being in a neighbours shadow and receive maximum solar energy during winter. The recommended key zones to channel this solar access is into the Living Rooms. The Living rooms should be the first point of contact to receive that winter solar energy only to then distribute that energy to the remainder of the home. It is important to consider that a room that receives five hours of efficient solar heating on a clear day will have nineteen hours of fluctuating heat loss. Insulation: To insulate in one sense of the term is to quarantine. Insulation is effective in reducing the transfer of unwanted sounds as well as thermal energy, providing an adequate amount of comfort within the home and together with maintaining that comfort within the home. Insulation is manufactured in all forms of materials according to its purpose, insulation is made for cavity wall, framed walls, ceilings, roofs, floors and windows. The right amount insulation is measured on a case by case basis, so as stated before If you live in a naturally ventilated home in the northern areas of Australia, the aim of insulation is to reduce the amount of heat getting in without restricting the hot air escaping. Reflective insulation under the roof and in walls that are not permanently shaded should work well. Thermal Mass High thermal mass materials such as clay bricks are materials that have a thermal lag by holding on to and releasing the heat for longer when it is needed, slab on ground ,if not on the ground consider insulated floors or enclose the under floor space encouraging a connection with the ground temperature. Good passive design uses thermal mass to absorb excess heat from within a house during a summer day and dump it to cool night skies. In winter, solar energy heats up the mass during the day, then it is able to re-radiate that heat into the residence at night. It is critical that thermal mass is well insulated from external temperatures and that it is exposed to winter sun in cooler climate zones. Windows and Glazing The glass to floor percentage has a large influence towards achieving your thermal comfort. Glazing is both the biggest source of heat loss and heat gain. It has been noted that the ideal window design is where 30% of your window sill to eave height is where you have should have the top of the windows setback to your eave line. While this is not exactly practical it is important to ensure that your windows are adequately shaded in summer and not overly shaded in winter. Additionally ensure that your windows are not excessive of 30% of you floor area and that they follow the rules of correct orientation. Shading External shading can provide a path of solar energy to enter your home as well as limiting its amount. The right approach can block up to 90% of the unwanted direct sunlight hitting your windows during summer. There are two common forms of shading to select from, either fixed shading devices such as the continues eaves of your existing roof line, or verandah like shading and there are those that are adaptable to seasonal changes. Fixed devices such as eaves and pergolas are the more common and well known approaches to the provision of shading, however these can be designed to allow the winter sun to enter but exclude the hot summer sun. There is a lot to consider when designing a passive design, it best to consider these factors thoughtfully before proceeding to the final design. A good solar passive design is achievable (especially orientation and location of rooms) when these principles are established to begin with. It is a common misconception that good insulation and top of the range products will fast track a building to becoming a good passive design building.

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