Factsheet 1. Solar passive design – combining orientation, thermal mass and windowsFactsheet 2. Insulation – retaining the heat in your home, not heating the neighbourhoodFactsheet 3. Sealing – eliminating draughts is crucial to a comfortable and efficient homeFactsheet 4. Heating – the most important home appliance purchase you will makeFactsheet 5. Hot water heating – the second-largest energy user in cold climatesFactsheet 6. Balancing the double-edged sword of windowsFactsheet 7. Understanding Energy – basics for HomeownersFactsheet 8. Site SelectionFactsheet 9. Energy EfficiencyFactsheet 10. Green Healthy MaterialsFactsheet 11. LightingFactsheet 12. Ventilation and CoolingFactsheet 13. Waste Management

1. Solar passive design – combining orientation, thermal mass and windows

There is one form of energy that is easy to access with clever building design, and completely free – the Sun! Correct application of the principles of solar passive design allows any building to trap the heat contained in sunlight as free heating in winter, while minimising entry of sunlight to the building in summer to prevent overheating. This can lead to greater comfort, low or no heating and cooling costs, and a significantly smaller environmental footprint for passive solar buildings.

Sun angles in GoogongEarth’s vertical axis, the line around which the planet spins, is tilted 23.5° from vertical. As Earth orbits the Sun, this tilt means that the angle of incoming sunlight changes relative to the ground. This effect causes the seasons and also influences the way buildings are affected by the heat in sunlight.

In Googong, at latitude 35.4°, on the summer solstice (December 22) at midday the Sun is 78.1° from horizontal, almost directly overhead. On the winter solstice (June 22) at midday, the Sun is 31.1° from horizontal, low in the northern sky. The Sun moves between these extremes at roughly 8° per month. Properly accounting for this change of Sun angle when orienting and designing a house can significantly reduce the need for heating and cooling. This in turn improves comfort, reduces energy consumption, energy bills and greenhouse gas emissions. Here is a useful application for you to visualise where the Sun is at any time of year (set to Googong, although you can change it to anywhere on the planet): http://www.suncalc.net/#/-35.3916,149.2348,12

Sun angles and building orientationYou do not need to know exactly where the Sun will be on every day of the year to understand how to orient your home – it is simply a matter of orienting to maximise incoming sunlight in winter and minimise incoming sunlight in summer. Put simply, to take advantage of solar passive design, your home should be oriented with the long axis as close to true east-west as possible. This maximises exposure of the building's surface area to the north, maximising the sunlight entering the building’s windows in winter, helping to warm it during the day. This orientation also minimises exposure of the building to the east and west, which minimises sunlight striking the building in summer, keeping it cooler during the day in summer. The correct orientation helps in both seasons!

Figure 1 – the impact of sun angles

Figure 2 – correct orientation maximises exposure to sunlight in winter, minimises exposure to sunlight in summer

Thermal mass – storing the heat in sunlightThermal mass is the ability of a material to absorb and retain heat. All materials have some degree of thermal mass, but many cannot store large quantities of heat (e.g. wood, plasterboard), while others re-radiate heat rapidly rather than retaining it (e.g. metals). Water has the highest thermal mass of any common material on Earth, but we cannot build with water, so the best thermal mass for building includes heavy materials such as concrete, brick and stone.

Thermal mass materials absorb heat from the air when they are cooler than the air around them, and release heat to the air when they are warmer than the air around them. They also absorb heat from radiant heat sources like sunlight or heaters.

The best way to use high thermal mass materials in building is to place them inside the building where they will be hit by sunlight during the day in winter – in front of north-facing windows is ideal – but are shaded from sunlight in summer. Used in this way, the high thermal mass will absorb the heat from the sunlight which strikes it during the day, warming the thermal mass. Then, when the air cools below the temperature of the thermal mass at night, it will start to release the heat absorbed during the day. This heat absorbing and releasing property of high thermal mass materials acts to reduce temperature fluctuations within the house, making it more comfortable.

Windows – letting the sunlight in!Solar passive design requires sunlight to enter a building in order to be useful. This is called solar access. Sunlight that hits external walls is of little benefit, even if it strikes a thermal mass material like brick, because that brick is outside the building envelope and has insulation between it and the living area you are trying to keep warm. So, careful positioning of appropriate windows to allow winter sunlight access to internal thermal mass is extremely important.

Most heating is used in common living areas, so if possible they should face north and feature large, north-facing windows (see Design). Double (or triple) glazing will not significantly reduce the amount of sunlight penetrating a window – after all, double glazing is simply two panes of glass with a gap in-between. However, double glazing will help to keep in the heat by reducing conductive heat loss, so it is preferable to single glazing. Regardless of glazing type, insulating internal window coverings, such as pelmeted multilayered curtains or honeycomb blinds sealed to the architraves, are necessary in a cold climate like Googong to help keep the warmth in at night.

In summer, it is preferable to eliminate solar access through windows because the heat in sunlight becomes trapped in the house, especially if it is well sealed and insulated. Eaves and other kinds of structural overhang are designed to block out sunlight when the Sun is at a high angle in the sky in summer, but any east/west/north windows exposed in summer may require further shading using external coverings such as awnings or roller shutters (see Shading). Clever design to prevent sunlight from entering your home in summer will keep it much cooler.

For more detailed information: http://www.yourhome.gov.au/passive-design/.

2. Insulation – retaining the heat in your home, not heating the neighbourhood

Googong has long, cold winters, so it is essential to have some form of heating. Whether heating is supplied by the Sun or an energy source like gas or electricity, it is crucial to keep this heat in your home. The longer the heat remains the less work the heater has to do, the less energy it uses, the more comfortable you are, and the lower your bills and environmental impact. Heating and cooling makes up 60% or more of the energy consumption of most households in the Capital Region, so major savings can be made by reducing the need for heating and cooling. Insulation helps reduce use of heating and cooling by retaining heat in your home in winter and keeping it outside in summer.

What does insulation do?Unlike thermal mass materials which store heat, insulation slows down the movement of heat through the insulation. There are three different ways heat is transferred in and out of buildings:

conduction: heat that moves through ceilings, walls, windows, doors and floors, radiation: electromagnetic waves like the heat in sunlight, and, convection: air that moves in and out through gaps in the building (see Sealing).

Different kinds of insulation slow down the movement of different types of heat, and the more complete the insulation coverage the better it is at slowing down heat movement and keeping your home at a comfortable temperature all year around.

Different kinds of insulation and how they workThere are two distinctly different kinds of insulation which do very different jobs: bulk insulation and reflective insulation. It is important to understand the different ways they work.

Bulk insulation comes in the form of batts or loose-fill and is made from bulky materials like fibreglass, rockwool, cellulose, polyester, or sheep’s wool. The tiny pockets of air trapped within these materials make them resistant to the conduction of heat – that is, the heat that moves through things when there is a difference in temperature on either side of them, in this case through the ceiling, walls and floor of your home. The temperature difference between inside and outside at Googong on a winter's night can be 20°C or more, so it is an excellent idea to have high levels of bulk insulation in your Googong home.

Thicker insulation means more air pockets and greater effectiveness at slowing the conduction of heat in either direction, so bulk insulation will help you in both seasons, more so the greater the temperature difference between inside and outside. This principle of trapping small air pockets to

Picture 1 – bulk insulation batts (left) and a roll of reflective insulation (right)

reduce conduction of heat applies in all contexts: it is the same way insulating window coverings and double glazing work, and even the way clothing works to keep you warm.

Reflective insulation (aka sarking, sisilation, anti-con) comes in rolls or boards and looks like aluminium foil. It acts as a mirror to radiant heat – that is, heat in the form of electromagnetic waves, such as the heat in sunlight or the heat emitted from bricks, tiles, concrete or metal that is exposed to sunlight for long periods. Reflective insulation is best at reflecting radiant heat away from the building interior in summer, but will not help much in winter because most winter heat loss in cold climates occurs as either conduction (which is what bulk insulation is designed to reduce) or convection (air moving through gaps in the building envelope).

How much insulation do I need in Googong?It is standard practice to install both bulk and reflective insulation in modern housing, but from a home-owner’s perspective it is also a good idea to know exactly how much and what kind of insulation are being put into your home, and where.

The effectiveness of bulk insulation is measured in R-values. R stands for 'resistance to heat flow', and a very rough rule of thumb is that 5 cm thickness of standard bulk insulation materials corresponds to R1 insulation value, although this varies depending upon the insulation material used. A high level of bulk insulation is an excellent idea in a cold climate like Googong: install R5 bulk insulation above the ceiling, and at least R2 bulk insulation in the walls (and under the floor if it is suspended – if not, the slab edge should be insulated at the very least, and preferably there should be insulation underneath the slab as well). Reflective insulation should also be installed under the roof and in the walls.

Installing high levels of bulk insulation in the ceiling and walls, and wrapping the house in reflective insulation, translates to greater comfort year-around, and less need for heating and cooling than an under-insulated or uninsulated building. This in turn will improve the comfort of the house and save you lots of energy and money over time from avoided heating and cooling.

Full coverage is crucial!Even small gaps in insulation reduce its effectiveness greatly. For example, a 200m² R5 insulated ceiling with 10m² of gaps in the insulation would reduce the total ceiling insulation value to about R2.3, and even 5 m² of gaps in insulation would reduce it to just over R3.1, which means higher energy consumption and bills for heating and cooling. So, try to minimise the number of holes in your ceiling insulation by avoiding downlights, installing heating/cooling that isn't ducted through the ceiling, and otherwise minimising penetrations through the ceiling (see Sealing). Also, remember to stick a batt on your manhole cover.

For more detailed information: http://www.yourhome.gov.au/passive-design/insulation and http://www.yourhome.gov.au/passive-design/insulation-installation.

3. Sealing – eliminating draughts is crucial to a comfortable and efficient home

Googong has long, cold winters, so a high level of insulation is essential to keep your home comfortable and energy efficient. However, insulation alone is not enough to retain the heat – draught sealing is also absolutely essential to keep the warm air in! There is no monitored regulatory standard for air leakage from Australian houses, but that does not mean that draught sealing is not important. To the contrary, paying attention to draught sealing during construction is very important as it is much easier and cheaper to get it right from the start than having to rectify it later, and a high level of draught sealing will potentially save you a lot of energy and money over time.

Measuring air leaks in housingThe most common measure of air leakage from housing is Air Changes per Hour at 50 Pascals, aka ACH50. This is determined using a blower door – an apparatus incorporating a powerful fan that fits on an external door – to create a 50 Pa pressure difference between inside and outside the house. The rate at which the house loses pressure is then measured. A decent ACH50 is 7, the lower the number the better. The most stringent energy efficiency regulation in the world, German Passivehaus, requires an ACH50 of 0.6, while Australian housing often has an ACH50 of 15 or higher.

There are local companies that leakage test houses, pinpoint the location of leaks, and make recommendations about how to address them. However, it is cheaper and more effective to make sure your house is properly draught sealed during construction, so it is a good idea to speak to your builder about their use of draught sealing techniques and devices.

Where are the common air leaks in housing? There are many potential sources of air leakage in new houses including:

downlights or recessed lights door and window framing (gap

between window/door frame and wall frame)

floor to wall and wall to ceiling joints (can be hidden behind skirting/cornices respectively)

internal wall cavity sliding doors (cavity in wall not sealed properly) and built-in wardrobes

evaporative cooling vents wall-mounted reverse cycle air-conditioners (RCACs) gas or wood fireplaces or heaters with chimneys or flues plumbing and gas penetrations, phone and television cable penetrations doors (gap between door and floor, gap between door and doorframe) dog/cat doors exhaust fans (if not fitted with a draught sealing device, including clothes dryer vents) electrical sockets

Gaps and cracks can develop over time as a building settles, and seals on doors (especially sliding doors) and windows can wear out, so it is a good idea to address air leakage every few years as an ongoing maintenance issue (see DIY sealing videos here: http://www.greenityourself.com.au/ ).

Figure 1 – possible air leaks from housing

How can air leakage be addressed during construction?Each source of leaks requires a different solution, but most are easy enough to apply during construction if sufficient care is taken:

Downlights or recessed lights: avoid installation (cheapest/easiest solution); or, install high temperature-resistant LED downlights1 with sealed fittings, and fire retardant, insulating downlight covers2 in the ceiling above the fittings – this allows insulation to be installed up to the cover.

Door and window framing: appropriate sealing tape, caulking or foam sealant during construction.

Floor to wall and wall to ceiling joints: appropriate sealing tape, caulking or foam sealant during construction.

Internal wall cavity sliding doors and built-in wardrobes: the cavity into which a sliding door slides should be enclosed in all directions, as should the space above and below built-in wardrobes.

Evaporative cooling vents: during winter, attach removable Heat Saver3 covers, an Australian invention. Remove during summer to allow for evaporative cooler operation.

Wall-mounted RCACs: appropriate sealing tape, caulking or foam sealant during construction.

Gas/wood fireplaces/heaters with chimneys/flues: can be tricky and must be treated carefully – discuss with your builder and/or heating specialist.

Plumbing and gas penetrations, phone and television cable penetrations: appropriate sealing tape, caulking or foam sealant during construction.

Doors: many doors now come installed with seals, but if not, add a bottom door draught stopper and appropriately thick draught sealing tape around the doorframe, both available at any hardware store. Also, draught seal the door to the garage (often forgotten), and doors such as the laundry door, which can potentially create an ‘airlock’ in conjunction with the back door.

Dog or cat doors: install airlock pet doors. Minimise the number installed.

Exhaust fans and Tastics: only install automatically self-sealing exhaust fans and Tastics.

Electrical sockets: install airtight electrical sockets and socket plug covers for sockets not in use.

All of these products can be sourced with minimal internet searching, and the extra upfront cost of properly draught sealing your home will pay itself off rapidly.

Ventilation and moistureA well sealed house will require some level of ventilation, depending on exactly how well it is sealed. For example, houses meeting or close to the Passivhaus standard require heat recovery ventilators (HRVs) for constant ventilation, while a well sealed Australian house could probably get by with active ventilation by the occupants (ie. opening doors and windows as required).

To avoid problems associated with moisture buildup, wet areas (kitchen, bathroom/s, possibly laundry) should have externally vented, self-sealing exhaust fans which are used whenever a moisture-creating activity, like showering, cooking, or drying clothes, is performed.

For more detailed information: http://www.yourhome.gov.au/passive-design/sealing-your-home.

1 LEDs degrade more quickly under elevated temperatures. See detail here: http://efficiencymatrix.com.au/downlight-cover-compatible-led-products/ 2 Such as these: http://www.downlightcover.com/index.html or these: http://efficiencymatrix.com.au/.3 See here: http://www.heatsaver.com.au/

4. Heating – the most important home appliance purchase you will makeMore than half of all the energy consumed in your Googong home will likely go to heating, so the kind of heating you install is a very important decision. Upfront cost is an important factor when buying a heater, but so is the efficiency of the heater because this influences the size of ongoing heating costs. Locking in a low efficiency heating option can cost you thousands of dollars more than an efficient heater over the life of the equipment. So, it is important to choose your heater carefully, and investing more upfront can save you a lot of energy and money over time.

It is an assumption today that central heating should be installed in every house, but this is a very modern idea as central heating was not so common even 20 years ago. Rather than assuming you need central heating, which can be far more costly to run than room heating, carefully consider your heating requirements. There are two main questions you should ponder before buying a heater:

1. Should I invest in central heating or room heating? What are your patterns of space usage within the home? For example, do you spend most of your time in the living room-kitchen area, or will you use most of the house most of the time you are home? Where are you most likely to spend time during the day/at night? These questions are important because they will help you to determine whether you need central heating or not.

2. Do I prefer or require a certain kind of heating?Convective heaters send out warm air to fill a room e.g. gas ducted and gas wall-mounted heaters, reverse cycle air-conditioners (RCACs). Convective heating can be an issue for people with asthma or chronic allergies as air movement can stir up allergens. Radiative heaters send out radiant heat to heat objects directly, and more slowly heats the air in a room e.g. hydronic radiators, bar radiators.

Efficiency in electrical heaters and gas heatersThere are two distinct kinds of electrical heating: electric resistance heating, and RCACs (aka heat pumps). Electric resistance heating, including column, panel, radiator and fan heaters, provides about one unit of heat output for each unit of electricity input – in energy terms, think of them as “one in, one out”. On the other hand, RCACs use electricity to draw heat from outside air, so typical new RCACs can produce up to four units of heat output for each unit of electricity input, depending on the outside air temperature. So, RCACs are far more efficient than electric resistance heaters per unit of electricity consumed, and electric resistance heaters should be avoided if possible.

The efficiency of gas heating depends on the thermal efficiency of the machine – that is, how good the heater is at separating heat from the noxious gases exhausted through the flue. Thermal efficiency for typical gas heaters varies from 60-85%, so 60-85% of the heat produced by burning the gas is sent to heat the home, while the rest of the heat is lost with the exhaust gases.

Whatever kind of heating you buy, always buy the most efficient model you can afford, even if the upfront price is a little higher – extra efficiency is likely to pay off the added upfront cost rapidly. To determine the efficiency of a heater look at the Energy Star label and/or discuss with a heating specialist.

Types of central heatingCentral heaters are powerful devices capable of heating your entire house. As such, central heaters also use a lot of energy, which means they can be costly to run and potentially have a large environmental footprint. If installing central heating, it is essential to install zoning, which should

help to limit your heating to the areas of the house that are in use. The flexibility of zoning depends on the type and brand of heater, so shop around if you require highly flexible zoning.

Hydronic heating: hot water pumped through in-slab pipes (make sure to insulate the slab!), radiators, or a combination of both in two storey houses. The water is typically heated by a gas furnace or heat pump, and although rare, solar is also possible. Hydronic heating is the most efficient form of central heating, is zonable to each room in the house individually, produces radiant heat and also warms the air in a room. It is generally more expensive upfront than ducted heating.

Ducted heating: warm air pumped throughout the house through insulated ducting. The air is produced by a gas furnace or heat pump. Ducted heating is zonable, but generally to areas and not to every room individually, produces convective heat rapidly, and should be installed under the floor if possible (installing it in the roof punches holes in your ceiling insulation!). Avoid putting vents in rooms that do not need or are not suitable for convective heating, such as bathrooms/laundry.

In-slab electrical heating: electric resistance wires running through a slab. It is very inflexible and expensive to run. In-slab hydronic is a far more flexible and efficient choice.

Heat recovery ventilation (HRV): used in conjunction with passive solar design, highly efficient.

Types of dedicated room heatingRoom heaters are usually dedicated to a particular room (sometimes two rooms). They are less powerful than central heaters because they are designed to heat smaller spaces, and are consequently less costly to run. If you typically use only certain parts of the house, such as the living area and master bedroom, it makes sense to install room heating instead of central heating.

RCACs: a compressor outside linked to a wall unit in one or a number of rooms, pumps out warm air. New models can be highly efficient and effective at low temperatures, but be sure to check with the manufacturer for an appropriate model. RCACs can also be used for cooling in summer.

Flued gas space heaters: mounted into a wall, or portable with exhaust duct through a wall/window, pumps out warm air. Can heat a room rapidly and some models are relatively efficient. Unflued gas heaters should be avoided as they are potentially dangerous.

Portable electric space heaters: come in many forms – column, panel, bar radiator or fan heater. They are cheap to buy but relatively inefficient and expensive to run, should only be used if there are no other alternatives. Radiant heaters can be useful in bathrooms (e.g. heat lamps in Tastics).

Wood heaters: come in a variety of forms including open fireplaces, slow combustion stoves and pellet heaters. Fireplaces are very energy inefficient, while slow combustion stoves create a large volume of unhealthy fine particle pollution. Sourcing sustainable wood can be an issue. In a residential development like Googong, try to avoid wood as the primary source of heating.

How to use heatingThere are five determinants of heating costs:

1. The efficiency of the building at retaining heat: invest in high levels of insulation, draught sealing, and even passive solar design if possible.

2. The efficiency of the heater: always buy the most efficient heater you can afford!3. The space the heater has to heat: minimise space heated using room heaters or zoning.4. The length of time the heater operates: use heaters only when you are home and benefiting

from the heat. Turn them off overnight and during the day when not home. Use a timer switch to turn the heater on before you get up and before you get home!

5. The heater’s thermostat setting: 16-20°C is comfortable for most, every degree you increase the thermostat will increase your heating costs by 5-10%.

For more detailed information: http://www.yourhome.gov.au/energy/heating-and-cooling.

5. Hot water heating – the second-largest energy user in cold climatesHot water on demand is one of the great luxuries of modern civilisation, and choosing an efficient hot water heater is also important. Hot water heating uses the second most energy after space heating in a typical cold climate household, and hot water heaters usually last 15 years or longer, so choosing an inefficient model will cost you a lot of extra energy and money over the lifetime of the heater.

Some hot water basicsWhen designing your home consider where you put the wet areas that will require hot water. It is best to group these areas together as much as possible, and situate the hot water heater nearby to reduce pipe run. This minimises installation cost, saves a huge quantity of so called ‘dead water’ (remnant cold water in hot water pipes that is wasted while waiting for new hot water to arrive), and means that hot water will be delivered at close to the temperature it leaves the hot water heater. Another way to deal with dead water is a dead water diverter4.

If most wet areas are grouped together but there is one distant wet area, such as an ensuite, consider a separate instant hot water heater for the ensuite. Also, always insulate hot water pipes all the way from heater to tap. It is mandatory to install at least three-star showerheads and fittings in Googong, and these fittings will help you to save a lot of water and energy.

There are regulations for the storage temperature of hot water (60°C) to limit the risk of Legionella bacteria, and also the delivery temperature of hot water (50°C) to reduce the risk of scalding. Discuss these issues with your plumber for more information.

Types of hot water heaterWater takes a lot of energy to heat, so hot water heaters are powerful appliances that use large quantities of energy. It is important to select a hot water heater that effectively delivers the volume of hot water your household demands, but does so using as little energy as possible. Selecting an efficient hot water heater is a great way to help reduce your energy bills.

Hot water heaters are classified according to both the energy source they use and whether the hot water is stored or produced when needed (usually called ‘ instant’, ‘on demand’ or ‘continuous’). Since a typical household usually requires hot water for only an hour or two per day, instant hot water heaters are much more efficient than storage hot water heaters – storage tanks are effectively large kettles that run 24 hours a day with the thermostat set to 60°C5, whereas instant hot water heaters only produce hot water when needed. Solar hot water heaters are an exception to this rule.

Solar hot water heaters are the most efficient kind of hot water heating because in Googong 50-80% of the energy used to heat the water comes free from the Sun, depending on how much water the household uses. During the day water is warmed by sunlight and recirculated through an insulated storage tank to keep it hot. If necessary, an electric or gas booster increases the hot water temperature at night, or when there has been an extended period of cloudy weather.

An electric booster is usually an element in the tank, whereas a gas booster is a separate gas instantaneous hot water system. Gas boosting is more efficient than electrical boosting since the latter sometimes operates when not needed. It is a good idea to turn off electrical

4 ...such as: http://www.redwater.net.au/ although there are a number of brands on the market.5 This is the government-mandated temperature for hot water tanks to reduce Legionella risk.

Picture 1: evacuated tube solar

boosters during the warmer months – make sure a cutoff and/or timer switch is installed for electrically boosted systems. Also, buy a model designed for sub-zero temperatures to avoid damage on cold nights.

There are two kinds of solar hot water heaters: flat panel and evacuated tube. Both do a good job, although evacuated tubes are more efficient (and usually more expensive) than flat panels. The solar panels/tubes must have access to the Sun, so they should face north and be un-shadowed by trees or buildings and meet Googong design requirements. There is a rebate available for installing a solar hot water heater under the Small Scale Renewable Energy Scheme6.

Gas (and electric) instant hot water heaters heat water only as you need it, and they never run out of hot water. Gas instant hot water heaters are now very common in the Capital Region because they are far more efficient than storage tanks. Separate controllers can be installed at each hot water tap, so each controller can be programmed to deliver water at a given temperature, which can eliminate the need for mixing with cold water, saving energy and reducing risk of scalding. In the past, instant hot water heaters have sometimes had problems with low flow showerheads, so make sure to install an appropriate model that can deliver hot water at low flow rates. Electric instantaneous hot water heaters powerful enough to service a house require three-phase power and are very uncommon here, but they do exist7.

Heat pump storage hot water heaters operate on the same principle as reverse cycle air-conditioners – they use electricity to draw extra energy from the outside air. This means they are significantly more efficient than standard electrical or gas storage tanks, although their efficiency decreases with the temperature of the outside air. If you buy a heat pump, make sure to purchase a model that is suitable for the sub-zero conditions of Googong winters, and try to site it on the northern side of the house where the air will be warmest in winter. Noise can also be an issue for heat pump hot water heaters, so think carefully about the effect of noise on you and your neighbours before buying one. There is a rebate available for installing a heat pump under the Small Scale Renewable Energy Scheme8.

Storage tank hot water heaters are the cheapest hot water heaters upfront, but also by far the least efficient, which means they are expensive to run. Tanks come in a range of sizes and can be heated by electricity or gas. If you buy a storage tank hot water heater make sure to size it appropriately for your needs because oversized tanks cost significantly more to run for no benefit. Try to avoid storage tank hot water heaters and buy a solar or instant system instead.

Hot water behaviourMost hot water is used in the bathroom for showering, baths and hand washing, followed by the laundry and kitchen. Purchase the most water efficient appliances possible, and reflect upon behaviours like showering time, clothes washing temperature, how you use the dishwasher, etc. because wasted hot water results in wasted water, energy and money from your pocket.

For more detailed information: http://www.yourhome.gov.au/energy/hot-water-service.

6 See here: http://ret.cleanenergyregulator.gov.au/hot-water-systems.7 .For example: http://www.stiebel.com.au/water-heating#instant-hot-water-system-3-phase-electric.8 See here: http://ret.cleanenergyregulator.gov.au/hot-water-systems.

Picture 2: instantaneous gas

6. Balancing the double-edged sword of windowsA house without windows is a bunker, and no one wants to live in one of those, so glazing is an essential part of any house. Windows have some wonderful benefits – they let in light, enable views, and enhance the feeling of space in a room – but they also have downsides which must be carefully managed to maintain energy efficiency.

Windows are composed of two main elements: the glazing, which is the kind of glass in the window, and the framing, which holds the glass in place. Both window elements are important for energy efficiency because both can lose heat very rapidly in a cold climate like Googong’s – in extreme cases, up to 40% of heat loss from a house in winter can be through the windows!

There are other aspects to windows that also should be carefully considered, such as how many and what size they should be, which directions they should face, whether they require solar access in winter or shading in summer, and whether tinting is appropriate.

Energy efficiency and windows – positives and negativesOn the positive side, north-facing windows allow a lot of sunlight in during winter which can warm a house during the day and, if used in conjunction with thermal mass, can even help to keep it warm on cold winter nights. On the other hand, sunlight through windows in summer can rapidly overheat a well sealed and insulated house, so it is important to block sunlight from striking the glass during the summer using eaves or other external shading devices (see Shading).

On the negative side, windows are very poor insulators, so they allow a lot of heat to conduct in and out of the house. In winter, when single glazing has a similar temperature to the outside air, windows also create convection currents (see figure 1), cooling the warm air that flows past them and creating cold draughts at floor level. Some windows can also become leaky, especially after a significant period of use, which makes them a potential vulnerability in a well sealed house.

R-values and U-valuesUnlike insulation and other building products where R-values (resistance to heat flow) are used to denote insulating effectiveness, window manufacturers use U-values, the inverse of R-values (U=1/R). U-values tell you how quickly a window will conduct heat. Do not make the mistake of buying a window with a high U-value – with U values, the LOWER the better.

WERS – the Windows Energy Rating SchemeIt is a requirement that all windows for sale in Australia are tested on a range of qualities: U-value (Uw on WERS, the rate at which a window conducts heat), Solar Heat Game Coefficient (SHGC, the amount of heat in sunlight that passes through a window, measured 0-1, higher means more heat), Tvw (visible light transmittance, measured 0-1, higher means more light), and AI (air infiltration, how well a window seals). Test results are published on the WERS website (http://www.wers.net/wers-home). WERS also has a useful star rating system for the effectiveness of each window in terms of heating (keeping the heat in) and cooling (keeping the heat out).

Different kinds of glazingSingle glazing has been standard in Australian housing for as long as Australians have built houses, however it is not suitable in cold climates like Googong. Glass has minimal insulation properties, so single glazed windows are roughly the same temperature as the outside air. As a consequence, in

Figure 1: cold window creating convection current

winter single glazing creates large cold surfaces in rooms with external windows, and conduct heat out of the house rapidly, as well as creating uncomfortable convection currents. Single glazing can also cause condensation issues due to the low temperature of the glass. Single glazing typically has U-values of 5 or higher (R-values of 0.20 or lower).

Double glazing, which consists of two panes of glass either side of a gap usually filled with argon gas or a vacuum, is becoming increasingly popular in new housing and renovations in Australia. It is significantly more insulating than single glazing, and acts to keep the interior pane of glass at a temperature closer to that of the inside air, reducing conductive heat loss and the likelihood of potential condensation problems.

For maximum effect, framing of double- (and triple-) glazing should be thermally broken aluminium, timber or uPVC, and the glazing gap should be 12-16mm. Not all double glazing is equal, and there is a wide range of U-values for double glazing from 1.4-6.4 (R-values of 0.71 down to 0.16), so it is a good idea to carefully check your double glazing on WERS to make sure you are getting what you pay for: a U-value of 3.0 or lower is a reasonable expectation from double glazing.

Triple glazing is similar to double glazing except there are three panes of glass and two gaps. Like double glazing, not all triple glazing is equal: U-values range from 0.8-4.0 (R-values of1.25-0.25; an R1.25 window is incredible, but expensive! You get what you pay for in glazing). If you are going to pay a premium for triple glazing, expect a U-value of 2.0 or lower.

Secondary glazing consists of various systems used to attach a secondary window pane to an existing single glazed window, which usually involve a secondary frame or attachment via magnets. Some secondary glazing is quite effective, with U values ranging from 1.5-4.7 (R-values of 0.67-0.21).

Glazing treatmentsLow emissivity glass has a coating applied to the inside of the glazing in the factory. This helps to reflect radiant heat back into the house, improving the glazing's performance as an insulator and lowering the window’s U-value. Low emissivity glass is often combined with double or triple glazing.

Tinting can be used to reduce heat gain or visible light transmittance through a window from sunlight, however it should be used with caution. External shading is often a better solution if the problem is summer heat gain. Tinting to reduce heat gain should definitely not be used on north-facing windows as that will reduce passive solar heat gain during winter. Tinting on east-, west- and south-facing windows is less problematic and can be useful in some situations.

Window coveringsIt is vital to install window coverings designed for insulating to keep the heat inside, and prevent convection currents, on freezing Googong nights. There are two kinds:

1. multi-layered curtains (at least two separate layers of fabric, preferably with a layer of insulating wadding in between) with a box or blind pelmet, sealed to the architrave at the sides with velcro, and just touching the floor, so as to trap cold air next to the window, or,

2. honeycomb blinds fitted inside the window reveals and bracketed to stop air leakage.

For more detailed information: http://www.yourhome.gov.au/passive-design/glazing.

The importance of framingWindow framing is often forgotten, but it is a very important part of any window. In a cold climate, standard aluminium framing loses heat very rapidly during winter. The nature of the framing also contributes to how well it seals. Double and triple glazing should always be installed in conjunction with insulating framing such as thermally broken aluminium, timber or uPVC, because standard aluminium framing significantly reduces the effectiveness of the expensive glazing.

7. Understanding energy – basics for homeowners

The most powerful tool you can use to reduce your energy consumption and maximise your energy efficiency is to understand energy, especially how it is measured, and how quickly particular appliances and activities consume it. Understanding the basics of energy will give you power over your energy consumption.

Household energy consumptionIn a cold region like Googong – technically referred to as a ‘heating climate’ – most household energy consumption goes to space heating, followed by hot water heating. Combined, these two activities typically account for 80% or more of a household’s total annual energy consumption9. Appliance use, lighting and cooking make up the rest.

The best way to think about household energy consumption is to break it down into two components:

1. passive household energy consumption, the rate at which the building use energy due to its design, level of insulation and draught sealing, and fittings; and the efficiency of the heater, hot water heater, lighting, appliances and standby power consumption; and,

2. active household energy consumption, which derives from occupants turning things on (and off!), and is based on household behaviour and level of energy consciousness.

Minimising passive household energy consumption is about designing and building your home so that it passively uses less energy than a typical house for important tasks like heating and cooling, hot water heating, lighting, refrigeration, cooking, clothes washing, and entertainment. This involves investing in the most efficient building and appliances you can afford.

Minimising active energy consumption is all about conscious behaviour towards energy -using devices: using heating moderately and only when you are benefiting from it (i.e. not overnight or during the day if you are not there), using hot water consciously, turning off lighting and appliances when they are not in use, turning off appliances at the socket to minimise standby power, etc.

Household energy consumption – some detailThere are some important units of measurement that you may have heard of but may not understand. They are explained below.

Watts (W) and kilowatts (kW): the RATE at which an appliance uses electrcity (or a photovoltaic solar panel produces electricity). A kilowatt is 1000W, just like a kilogram is 1000g or a kilometre 1000m. So, if you know the wattage of an appliance but need the kilowattage, divide the wattage by 1000!

9 This is an approximate figure and assumes a house with a storage tank hot water heater. Patterns of energy consumption vary from household to household due to a wide range of factors.

Kilowatt hour (kWh): a TOTAL QUANTITY of electricity . The number below the ‘kWh’ column on your electricity bill tells you how many kilowatt hours were consumed by all of the appliances used by your household during that billing period. The price of electricity currently ranges from about 20-40c/kWh depending on your location and contract.

If you know the wattage of an appliance, and how long it is on for, you can roughly calculate the total quantity of electricity used by the appliance using these equations:

rate (W) x time (h)= total (Wh)rate (kW) x time (h)= total (kWh)

Examples: a 100W appliance, such as a small-medium sized LED television or laptop, running for 10

hours, would use (100x10=)1000Wh or 1kWh a 1000W hotplate running for one hour would use (1000x1)=1000Wh or 1kWh; a 4kW heater running for 15 minutes would also use (4x0.25=)1kWh.

Megajoules (MJ): a total quantity of energy . The number below the ‘MJ’ column on your gas bill tells you how many megajoules of gas were consumed by all of the gas appliances used by your household during that billing period. The price of a megajoule of residential gas currently ranges from about 2.2-3.0c/MJ depending on your location and contract. The rate at which gas heaters consume gas is quoted in MJ/hr.

If you need to, you can convert between kilowatt hours and megajoules since they are both quantities of energy: 1kWh = 3.6MJ

Greenhouse gas emissions: as a rough rule of thumb, 1kWh of electricity from the grid generates about 1kg of carbon dioxide in NSW/ACT. This number varies from State to State depending on the predominant source of the power generation (black coal, brown coal, natural gas, wind, solar). If you choose to buy Green Power, this number drops to close to zero carbon dioxide emissions because you are effectively buying your power from the share of the grid that is renewable.

R-value (and U-value): Every building element – ceiling, walls, windows, doors, and floor – has an R-value: its resistance to transmission of heat. The higher the R-value the better because that translates to more resistance to heat loss in winter (and conductive gain in summer). In this climate, some desirable R-values are: ceiling batts – R5floor batts – R2.5 windows – R0.33 (double glazed, low-conduction framing)wall total – R3 (R2.5 batts +wall itself)doors – most doors do not quote R-values in specifications

U-values are the inverse of R values (U=1/R): they measure how quickly heat is transmitted through a building element. U-values are typically quoted for windows, while R-values are usually quoted for everything else. The lower the U-value, the less heat is transmitted through a window, so when shopping for windows the lower the U-value the better.

Standby power: many appliances use power even when they are NOT ON! Every 10W of standby power around the house equates to about 80kWh/yr10 (about $32/yr11 in Googong!) of electricity consumed for no benefit, so it is a good idea to turn off all appliances at the power socket when not in use. If you cannot reach the socket, try using wireless remote switches or timer switches.

10 (10x24x365) = 87.6kWh/yr, -10% for operational time.11 80x0.40c=$32

20˚E

20˚E

8. SITE SELECTION

Site Orientation

Choosing the right site for your home is the single most important decision you can make in setting up the optimum conditions for a sustainable house. The climate in Googong makes it important to obtain as much advantage as possible from the warming effect of the sun, and the orientation of your block will facilitate this.

Ideally your site will face true north, with its long axis running as close to true east-west as possible. This will make it easier for your designer to gain the most benefit from the sun to provide warmth and energy for your home.

A slight deviation from true north can be accommodated without significant loss of solar access.

True North

15˚W

15˚W

Fortunately, the majority of building sites at Googong have a northern orientation which will make it easier to orient your building to capitalise on solar energy.

The position of the building on the site and the internal layout of the house in relation to the orientation of the site will vary from site to site depending on the direction of true north, the position of the road relative to the building and the location of adjacent structures.

Site Elevation

An elevated site will make it easier to capture cooling breezes in summer time whilst providing views over the development to the hills and landscape beyond.

Drainage will also be assisted by an elevated site, especially those sites which are above the street level, as this will facilitate drainage to the street stormwater system.

Building Position

It is tempting, and quite often done, to build on the best part of the site, however it is better to build on those parts of the site which are in the worst condition as the act of building will help repair that part of the site and the outlook from the building will then be to the most beautiful part of the site.

Building Orientation

EW

Diagram showing one example of lot orientation at Googong

Street

The building should face as close as possible to true north, with the long axis of the house running true east-west (like the site) with the ratio of length to width illustrated above, as this will enable as many rooms and spaces as possible to face north.

Wind and weather patternsObserve the direction of prevailing winds and weather in relation to the site to determine the best location for windows, shade and shelter. Position windows, doors and other openings to maximise the benefit from cooling breezes in summer but provide protection from harsh winter winds.

Neighbouring structures and solar access

Take note of neighbouring structures, whether natural (eg trees and other landscaping) or man-made (buildings) and the impact they may have on the solar access of your site and the wind and weather patterns. Tall trees or other structures to the north of your building site will impact on the availability of solar energy, but may also help in providing shade in summer and shelter from weather.

Zoning

Areas in the house where you will spend most of your time, apart from sleeping, will be best positioned on the northern side of the house as this will provide the best conditions for

comfort. Areas where activities don’t require similar levels of comfort (eg bedrooms, laundry, toilets etc) can be positioned on the south, east and west sides of the house.

9. ENERGY EFFICIENCY

Energy Efficiency is the single most effective way of reducing energy consumption and cost in the design and operation of your home. It applies to:

Building design (see also Passive Solar Design fact sheet) Appliances and other energy users (space heating and cooling, hot water systems,

lighting) Operational energy demand (for lighting, heating, cooling, ventilation, appliances)

Building Design (see the Passive Solar Design fact sheet)

1 Site location2 Orientation for direct solar gain3 Zoning for thermal efficiency4 Thermal mass5 Insulation6 Ventilation7 Glazing for direct solar gain8 Sealing of draughts9 Shade10 Landscaping

Energy Efficient Appliances

The type of appliances you chose and how you use them will have a big impact on the energy savings achieved in your home. Appliances include TVs, home entertainment systems, refrigerators, washing machines, dishwashers, blenders, grinders, mixers, irons etc.

The energy efficiency of appliances is required to be stated on the Energy Star label attached to the appliance and this star rating describes the performance of the appliance in relation to its energy efficiency. Appliances with a higher star rating use less energy and produce less greenhouse gas emissions. The average annual consumption for the appliance is stated in kWh per year.

The size of an appliance can also have an impact on its energy consumption, even if it has a high star rating, so choose the size of the appliance most appropriate for your needs.

Modern high tech electronic equipment is often fitted with a standby mode making it convenient to start up instantly when required. Unfortunately, in the standby mode, the appliance still consumes electricity, which can amount to 10-12% of its normal use, so it is important to ensure appliances are turned off at the power point.

A ’Green Switch’ is a wireless home energy control system which will help manage standby power use by making it easy to switch off appliances that are not in use.

A green switch comprises two units – a small portable remote control unit and a small ‘slave’ unit which plugs into the 240V wall socket, into which an appliance is plugged. The appliance can then be turned on and off using the remote control unit.

An alternative to a green switch is a ‘Master Control Switch’ which is a switch that can be installed over nominated circuits (power and lighting) to enable the fittings on the nominated circuits to be all switched off at once. For instance, when retiring at night, all lights and appliances in the house that are on (or are on standby) can be turned off from the one conveniently located position.

Ask your builder to install a Master Control Switch over nominated power and lighting circuits.

A ‘Smart Meter’ is normally installed by the electricity supply company and provides data that enable customers to make choices about how much energy they use by providing them with accurate real-time information about their electricity consumption.

Space Heating

In the cool climate of Googong, heating will most likely represent the majority of your energy consumption, so install the most efficient heating system available and ensure that the heat you generate is retained within the building by the use of thermal mass, insulation and draught sealing (see Passive Solar Design factsheet).

The amount of heating you need depends on many things, including your home’s star rating, extent of draughts and microclimate.

Options for space heating to achieve a comfortable home include:

Solar Hydronic Solar to air Reverse cycle air conditioning Electric Gas Solid fuel

Hot Water

Hot water is the next largest energy user after space heating. Purchase the most energy efficient hot water system available and ensure that it is positioned to maximise solar gain while minimising heat loss from the storage tank itself and from the pipework taking the heated water to delivery points.

The choice of the most appropriate system is detailed on the Hot Water fact sheet. An evacuated tube system would provide the most efficient water heating system in a location such as Googong as such a system will extract the maximum heat from the available sunlight.

Locating the system close to outlets is important to minimise runs to delivery points, so locating bathrooms close together can assist to reduce heat loss in pipework. Insulating the pipework will assist in retaining the valuable heat energy generated by the collector panel.

Lighting

Advances in lighting technology mean that energy efficient lighting is possible with no sacrifice in lighting quality. Older style incandescent light fittings which produced a significant amount of heat have been replaced by compact fluorescent and LED lamps with significant savings in energy consumption.

LED lamps in particular can reduce energy consumption by up to 70% compared to incandescent fittings and have lifetimes of 50,000 hours which make their initial cost more acceptable over the long term. LED lamps are also more reliable, efficient and operate at safe low voltages.

Lighting Plan

A lighting plan comprising natural daylight, low energy light fittings, lighting control systems and innovative circuitry can:

Provide a high level of visual comfort Use daylight via windows, skylights, skytubes and clerestory windows where

appropriate Have low energy requirements Include motion sensors for limiting the time lights are on and turn off when not

required Highlight the architecture and design Minimise consumption by designing circuits so that only lights that are needed are

switched on

Operational energy demandThe amount of energy consumed in your home will depend on a number of factors, not the least of which is the amount of time appliances, lights, air conditioning and heaters are switched on or left in standby mode, ready to leap into action in the blink of an eye.

Motion sensors and timers can save a lot of energy where, for instance, lights will only turn on when you enter a room or space controlled by the motion sensor. Lights will remain on as long as the person is in the room. The time length of the sensor can be adjusted to suit the activity.

As previously mentioned, forgetting to turn off appliances at the main power point can also contribute to significant ‘phantom’ energy use, which can amount to 10-12% of the appliance consumption.

Control systems and power management

Understanding your home energy use is a first step to managing and potentially reducing your energy consumption. A simple way to start coming to grips with your consumption patterns is to install a power usage meter which lets you measure energy use and calculate the running costs of different appliances as well as their greenhouse gas emissions.

Knowing which appliances consume the most electricity will help you choose when to use them based on the electricity rate at the particular time you plan to use them. For example, you may choose to use your washing machine during off-peak times when electricity is cheapest.

Wireless meters let you take readings without having to access the main socket unit.

More sophisticated (and expensive) systems operate as ‘data loggers’ which will monitor energy use over a range of appliances, including air conditioning systems. This type of system will be useful, to those seeking to make serious changes to their usage patterns.

Rating Tools

There are a number of house energy rating and modeling tools available in Australia for carrying out assessments of the thermal performance of proposed buildings. At present there are no accredited tools which measure overall environmental performance.

The accredited tools which have been developed to assess thermal performance include:

BERS Building Energy Rating Scheme, which is more applicable to tropical and subtropical climates

NatHERS National House Energy Rating Scheme is the framework tool used to assess thermal performance of house designs against minimum compliance standards set by the BCA (Building Code of Australia)

AccuRate Developed for thermal assessment in the ACT, now the standard tool for thermal assessment of residential buildings in Australia

First Rate Developed by the Victorian Government for use in Victoria

Ratings prepared by accredited assessors using the above tools are accepted by most authorities in Australia.

Using one of the above rating tools will enable the inclusion of factors which will facilitate the design of higher star rated buildings, with the potential for significant energy and water savings.

In NSW, new houses are required to meet minimum energy and water reductions mandated under the Government’s BASIX compliance scheme, which requires reductions of 40% in water and 40% in energy compared to standard houses. Houses in Googong are required to meet the stricter requirement of a 50% reduction in water use as part of the DA process.

The rating tools produce a ‘star rating’ which indicates the thermal performance of the building in its requirement for heating and cooling within a range or ‘band’ of energy consumption, measured in MJ/m2 per annum, required to achieve comfort levels as follows:

Star Rating Annual MJ/m2

heating and cooling1 2842 1863 1254 885 666 517 398 269 14

10 5

Recent research * by the CSIRO found that building a 5-star rated dwelling will provide improved thermal comfort whilst saving money both during construction and occupancy.

Links

NatHERS www.nathers.gov.auBASIX www.basix.nsw.gov.au/basixcmsCSIROwww.industry.gov.au/Energy/Pages/Evaluation5StarEEfficiencyStandardResidentialBuildings.aspx

10. GREEN MATERIALS = HEALTHY MATERIALS

All materials used in building construction will have an impact on the environment and potentially your health ranging from relatively benign to reasonably toxic.

To be considered ‘green’, healthy or ‘low impact’, building materials will have the following characteristics:

Renewable and abundant, low resource depletion Low embodied energy Non polluting Durable Recyclable and able to be re-used High recycled content Minimal impact on air and water quality Non-hazardous formulation (avoiding constituents such as formaldehyde, PVC) Equitable, local production 3rd party accreditation

Materials which are renewable and abundant will incur minimal resource depletion and come from diverse natural sources whose production has a low impact on the environment.

Low resource depletion materials include mud brick, rammed earth, reinforcing steel, particle board and plywood whereas materials requiring substantial resource extraction include metals (copper, aluminium) and plastics.

Embodied energy is the energy used to extract, transport, manufacture and fix in place. Metals used in building (eg copper pipe and sheet, aluminium extrusions) and some plastics (eg PVC pipes, ducts and conduits) have high embodied energy, whereas materials such as mud bricks, rammed earth, clay bricks and timber products have low embodied energy.

Durable materials will last longer performing their required function than inferior, cheaper materials and will therefore not require replacement for much longer.

Materials which are recyclable will have another life when they have finished their current function, so will reduce the need for new materials to be created. This also applies to how materials are fixed into a building, for example bolting members together can facilitate later re-use without damaging the original material.

Materials with a high recycled content include recycled timber (which can be 100% recycled), ‘green’ concrete with a cement substitute and a recycled aggregate content, building boards made from timber waste with a binding agent, steel reinforcement made from scrap metal.

Materials which ‘off-gas’ or emit harmful vapours, particles or toxins into the environment due to their manufacturing processes will have an impact on air quality over a long period of time, often resulting in VOCs (volatile organic compounds) being released into the

atmosphere well after the material has been fixed in place. Other materials, such as lead flashing, can contaminate the soil and waterways by carrying lead particles in rainwater.

This is amply demonstrated where lead flashing is used in conjunction with galvanised gutters resulting in corrosion of the gutters due to the galvanic reaction between the lead runoff in rainwater and the zinc in the galvanised gutters.

Materials with a non-hazardous formulation present no risk to builders or users by virtue of the nature of their constituent materials. E0 MDF (zero emission medium density fibreboard) boards for example use no toxic glues in their manufacture, so they don’t off-gas during use and present no problem to fabricators working with the material (cutting, sanding, drilling etc).

Where possible, materials which are derived and produced ethically via socially fair means and through local production will maximise equitability and local employment whilst minimising the environmental impact by virtue of the shorter distances required to transport the material in both raw and manufactured states.

3 rd party accreditation organisations will attest to the environmental impacts of mainly timber materials, eg the Australian Forestry Standard (AFS) and the Forest Stewardship Council (FSC) organisations which certify timber as being a single species from a managed resource, a mixture of species from managed resources or recycled material.

The following list comprises preferred materials with a low environmental impact:

Timber products generally, with AFS or FSC certification Recycled solid timber Plantation timber for framing, lining and cladding Green concrete with 40% less cement and 60% recycled aggregate Stone (sandstone, limestone, granite, marble) Natural insulation such as wool, mineral wool, paper Hay bales Straw based wall panels Cork, linoleum HDPE (high density polyethylene) drainage pipes Stainless steel mesh termite management Clay brick and tile Terra cotta Double and triple glazing in a timber or thermally isolated aluminium frame Zero emission MDF board (E0 MDF) Plant based oils, paints and, stains and beeswax Polyethylene electrical and data cables

The following are examples of materials which have positive ecological properties and contribute to a healthy environment both during construction and occupation.

Drainage pipesHDPE (High Density Polyethylene) drainage pipes

Adhesives and tile groutNon-polyurethane or formaldehyde based adhesives for carpentry and timber joinery generally

Paints, oils and stainsPlant based paints with no VOCs (volatile organic compounds) for both interior and exterior use. Linseed oil based finishes and natural waxes protect and enhance the life and appearance of timber

JoineryCupboard carcasses and other joinery items constructed from E0 MDF boards (zero emission, medium density fibre board) are VOC-free.

Ecoply plywood uses VOC free adhesives

Non chemical pest controlThe only non-chemical system for managing termites is a stainless steel mesh barrier (‘Termimesh’).

Where cost is a significant factor, low-impact chemical membranes which are impregnated with chemicals (eg ‘HomeGuard’ and ‘Kordon’) are approved under the Building Code of Australia for termite management.

Chemical spray/saturation techniques are also approved under the BCA but are to be avoided as the chemical residue remains in the soil for a considerable period after application and requires regular re-application.

Indoor Environment Quality-Sick Building Syndrome

Unhealthy/toxic materials pose a risk both to the environment and to those who use the materials as well as those who live within them. As buildings have become more airtight for energy efficiency reasons, so has the need to minimise the amount of emissions from building and furnishing materials released into the interior environment.

When chemicals build up in the internal environment and there is a lack of ventilation, sick building syndrome can develop, potentially causing headaches, fatigue, sleepiness, loss of concentration, nausea. This can be exacerbated by the type of lighting employed, the temperature and humidity of the air and factors relating to ability to control the indoor environment.

The following materials are unhealthy - some dangerously so and should be avoided:

Asbestos Lead Lead cadmium Mercury Chlorinated polyethylene Chlorosulphonated polyethylene Petrochemical fertilisers and pesticides Chlorofluorocarbons (CFCs) Phthalates chloroprene (neoprene) Polyvinyl chloride (PVC) Formaldehyde Wood treatments containing creosote, arsenic, cyanide or pentachlorophenal Halogenated flame retardants

11. LIGHTING

Lighting includes both natural and artificial light and the design of a lighting system will form an integral part of the overall sustainable design approach.

On average, lighting your home makes up 5-10% of your electricity bill, so increasing the energy efficiency of your lighting system will improve the overall energy efficiency of your home.

An efficient lighting system will:

Make use of natural light, so living areas including kitchen and bedrooms don’t require any artificial lighting during the day

Provide a high level of visual comfort Allow the efficient performance of a visual task Provide the best light for the task (how bright is bright enough) Provide controls for flexibility to minimize the number of lights required in a space and the

amount of time they are on through the use of motion detectors and timers, for instance Have low energy requirements by selection of energy efficient lights and lamps Create an atmosphere or ambience

Daylight

Sunlight is used (see passive solar design fact sheet) to provide both warmth to the interior of a house and light for daily tasks. Glazed windows, clerestory windows and skylights admit light to the internal spaces of buildings, and insulation in windows, walls, floor and roof provide the means to retain the warmth, whilst the position of windows and internal colour selection will assist in optimizing the use of daylight.

Glare arising from bright sunlight falling on work surfaces forms a distraction, reduces attention and causes fatigue to the eye. Glare can be avoided by carefully positioned external fixed shading and/or adjustable shading devices such as operable louvres, blinds and awnings.

Lighting Layout

Artificial lighting will provide lighting for those tasks where natural daylight is insufficient and at night. The layout of your lighting system will have a big impact on the comfort of the tasks and the energy consumption associated with them.

With the advent of low-wattage light fittings, such as CFLs (compact fluorescent lights) and LEDs (light emitting diodes), it is possible to design your lighting to minimize the number of lights turned on at any particular time and provide task lighting where, in the past, lighting of whole spaces was required to provide an adequate level of illumination for tasks and comfort.

This is not to be confused with ‘low voltage’ light fittings such as halogens, which provide more heat than light and contribute to excessive energy use.

Allow for lights which are not used for long periods to be fitted with a sensor to detect movement and switch on for a short period and turn off automatically. Timers can also be used to activate lights as a security measure when you are away from the house for any length of time.

Install a ‘Master Control Switch’ over nominated lighting circuits to enable fittings on these circuits to be all switched off at once.

Light fittings

Incandescent fittings produce light by heating a metal filament, which causes a lot of heat to be lost in generating light, consequently this type of fitting is no longer legally manufactured for sale in Australia except for stock which was made before the legislation came into force.

Traditional halogen bulbs also create lots of heat, which means that ceiling insulation must stay clear of down lights to avoid the risk of fire and this degrades the effectiveness of the insulation, which leads to significant heat loss through the roof space.

LED down lights however, produce almost no heat, and many types can be ‘capped’ – meaning you can run your ceiling insulation right over the top of them.

Ask your builder to recommend LED light styles.

This graph shows the improving efficiency of different lighting technologies over time. You can see that to generate the for same amount of light, a Halogen uses 60W, whereas an LED uses 4-5W

Passive cooling Passive solar heating with active heating from roof space

Summer Winter

12. VENTILATION AND COOLING

Natural ventilation Natural ventilation relies on natural air movement and is primarily associated with the provision of adequate cooling in summer. It can save significant amounts of fossil fuel based energy by reducing the need for mechanical ventilation and air-conditioning.

The principal factors affecting natural air movement around and within buildings are:

The site and local landscaping features The building form, orientation and envelope design, including position and size of

openings The internal planning of the building and room design

Influence of site and landscaping features

Local factors, such as wind conditions, topographic features such as hills, ridges and escarpments and landscaping elements such as trees, shelter belts and shrubs will influence the way air moves around the site. Local wind speeds can be estimated from Bureau of Meteorology wind data which needs to be moderated for the abovementioned local factors.

In summer, the ideal would be for light winds to provide sufficient internal air movement for thermal comfort during all but extreme conditions and for night time cooling of the building (‘night purging’).

The problem for temperate and cold climates in winter is to avoid excessive wind through ventilation openings and leaks in the building envelope.

Vegetation can help modify the external wind direction so as to enhance ventilation as well as cool incoming air. Dense shrubs and tree canopies should be kept clear of windows and other openings to minimise obstruction to air movement.

Sketches of summer passive cooling and winter passive solar heating and active heating from roof space

Casement sashes to catch breeze

Awning sashes

Prevailing breeze

The main design elements for passive cooling of buildings in a climate like Googong are:

Orientation for exposure to cooling breezes Increase natural ventilation Effective shading to reduce heat load Adequate levels of insulation Floor plan zoning to maximise comfort for daytime activities and sleeping comfort Appropriate windows and glazing to minimise unwanted heat gains and maximise

ventilation Landscaping for shade and cooling High thermal mass construction (see Passive Solar Design fact sheet)

The building form, orientation, envelope design and window openings

Naturally ventilated buildings should be oriented to maximise their exposure to the prevailing (summer) wind direction, with a relatively narrow plan form to facilitate the passage of air through the building (cross ventilation). Passive solar requirements (see Passive Solar Design fact sheet) will need to be optimised with ventilation requirements so both can contribute to thermal comfort.

Image courtesy Dick Aynsely Environment Design Guide

Windows should be located to receive the prevailing wind for summer conditions and should ideally be installed on both sides of occupied spaces for cross ventilation. The total area of windows on the outlet side of the building should be bigger than those on the inlet side to facilitate air movement.

Passive-design shade (eaves, roof overhang, awnings) will limit heat build-up in summer and admit the sun in winter.

Different window styles and sizes will provide varying ventilation rates. See diagram below.

French doors and wing wall

French doors with one leaf wall fixed

Wind Outlet

Internal resistance minimised

Louvres Horizontal & vertical sliding

Casement Awning Bi fold

Different window styles offer different ventilation outcomes

Louvre windows offer almost 100% opening area. Casement windows with friction stays can be up to 60% more efficient than other sash types or sliding doors on the windward side.

Sliding windows can be problematic in that they can only be opened half way and can’t be adjusted according to wind direction.

Short ‘wing walls’ can increase air flow through windows when the prevailing wind is not perpendicular to the window wall.

Internal planning and room layout

To facilitate the natural ventilation of rooms, the resistance to airflow through the building needs to be minimised. Air movement will be facilitated by large openings and by reducing the number of rooms through which the air has to pass.

Natural ventilation of a building

Landscaping for shade and cooling

Prevention of unwanted summer heat build-up is important in reducing mechanical cooling requirements, in particular air conditioning, and landscaping can contribute by providing shading to buildings and ground surfaces. Care needs to be taken to ensure that shading is not extended to solar collectors which will generally be on the roof.

Vegetation helps lower surrounding air temperature by evaporative cooling resulting from transpiration.

Plants and grasses can also help to reduce the heat load on exposed surfaces by the provision of a vegetative ground cover which obstructs the heating effect of solar energy.

In Googong, a minimum of 30% of the front garden area is required to be planted garden beds, minimising reflective surfaces, which will go a long way to reducing heat load from both direct and reflected radiant solar energy.

Carefully located planting can also be used to assist in funnelling cooling breezes into and around the house in summer and blocking cold winter winds.

Benefits from landscaping are:

Support for indigenous and endemic plant species and backyard food production Improved thermal and sound insulation Reduced heating and cooling requirements from the formation of microclimate Reduced stormwater runoff Increased biodiversity Encouragement for birds and other wildlife Amenity, aesthetics

Food Production

Using open space around the house for a vegetable garden can contribute to your food requirements, even if you only plant some herbs.

Permaculture gardening, no-dig garden beds and ‘wicking’ beds are simple ways to start creating a productive garden.

Your garden will benefit from the rich compost derived from a compost system or worm farm and will help to minimise the amount of waste generated from your house.

Green Walls and Roofs

Green walls (also known as ‘Living Walls’, ‘Vertical Gardens’ etc) are particularly useful where space is limited for a horizontal garden and if attached to a wall can help reduce the temperature of a building by evaporative cooling through the process of transpiration.

Green walls can also help filter and purify water which can be continuously cycled through the soil medium.

Green roofs are roofs planted with vegetation which can provide many benefits as follows:

Reduce heat load in summer and heat loss in winter Filter air and water pollutants Reduce stormwater runoff Adds thermal mass Encourages natural habitat creation

13. WASTE MANAGEMENT

A large percentage of waste going into landfill is related to the construction, demolition and renovation of buildings. Even more waste is produced during the occupancy of buildings through the consumption of goods and services.

This waste constitutes not only considerable environmental degradation but also represents a big financial burden for current and future generations.

Ask your builder to prepare a waste management plan to minimise, separate and recycle waste generated on building sites so that:

Waste going to landfill is minimised Emissions, pollution and contamination are minimised Scarce resources are protected Construction costs are reduced Tipping fees are reduced or negated

Design, detailing and specification stage

At the design, detailing and specification stage, make decisions which will have an impact on cost effective waste reduction techniques. Material selection and construction detailing strategies can have a big impact on the amount of waste material that is generated, as well as affecting the way the building is recycled later in life.

This includes errors in documentation which necessitate rectification or replacement of building elements incorrectly installed.

Consider the size, flexibility and adaptability of the project as this will affect the resource use per person and consequent waste, space allowance and energy use, as well as future recycling and/or re-use of the building and its components.

Life cycle analysis (LCA) of materials used in the construction can identify material durability, recyclability and disposability issues as well as environmentally damaging, toxic or waste-prone materials, which should be minimised or eliminated.

Buildings that are designed for deconstruction will consider materials and jointing methods which permit disassembly and deconstruction which will encourage re-use and recycling.

Prefabrication of certain building elements, eg roof trusses, precast concrete elements can eliminate on-site waste, whilst standardised work practices and full utilisation of offcuts can further contribute to resource efficiency and waste reduction.

Modular design that accommodates standard material sizes should be the norm. This is particularly relevant in wall linings where ceiling heights determine sheet size – perhaps it should be the other way round. Sheets are normally supplied in 300mm increments in size so offcuts are almost unavoidable unless the ceiling heights are 2400, 2700 or 3000mm.

Legislation, contracts, policies and Australian Standards can be barriers to greener specifications and the incorporation of reused, recycled and reconstituted materials.

Councils generally require a Waste Management Plan to be submitted with a Development Application, which applies to:

Site preparation (green waste) Demolition and destination of demolished materials Construction waste and destination of waste material Waste generated from occupancy (allow for compost heap or worm farm system)

Before starting to build

Make sure your builder has prepared a waste management plan that is communicated to suppliers, subcontractors, labourers and staff. Ensure this is monitored and adhered to.

Ask him to plan the site to reduce waste at different stages (excavation, building structure, envelope, interior fit out, finishing) and require subcontractors to adhere to the site waste management plan.

The following table illustrates typical construction waste generated during a build.

Waste Description

Percentage of total waste (by weight)

Soil 36Concrete based masonry

16

Brick and tiles 16Timber 10Vegetation 3Metals 2Plasterboard 2Hard plastic 1Paper 1Others 13Total constructionwaste

100

During construction

A considerable amount of waste material can be generated during construction, a large percentage of which can be avoided if sustainable practices (eg prefabrication, standardisation) are observed. It is in the builder’s interests, not to mention the environment’s, to minimise waste requiring disposal.

Ordering and purchasing

Estimate quantities accurately, aim for nil waste allowances and avoid over-ordering. Purchase materials and components that can be re-used or recycled. Plan to limit the number of skips used in accord with your total waste budget.

Packaging

Negotiate with your suppliers to:

minimise packaging in their deliveries only use packaging that can be re-used or recycled take back packaging once goods are unpacked

Site waste management

Include the waste management plan in site induction procedures and train labourers to observe the plan. Monitor the site waste management during construction.

Reward good progress.

Provide labelled receptacles on site for waste in the following categories and volumes:

timber recycling bin 3m3

mixed waste disposal bin 3m3

metals recycling bin 3m3

brick, tile and concrete recycling bin 3m3

During occupancy

This is more of a sustainable living issue, however waste management during occupancy will be more manageable if systems are designed-in to facilitate waste separation for recycling.

Install under-bench systems in the kitchen to encourage recycling at the source and ask your builder to allow for a compost system and worm farm in the garden are.

List of images:Solar orientation - both from Tony

Insulation - need a generic picture of bulk insulation batts (preferably installed tightly a cross ceiling) and a roll of reflective insulation to illustrate the difference between bulk and reflective insulation, source from wherever you like

Sealing - picture of leaks comes from Your Home manual (http://www.yourhome.gov.au/passive-design/sealing-your-home )

Heating – Star stick out picture comes from http://www.energyrating.gov.au/

Hot water heating - pictures come from the net, but they could come from anywhere. I suggest a picture of a solar hot water heater and an instant hot water heater as those are the two kinds of hot water heaters we are encouraging people to invest in.

Windows - convection current picture comes from : https://www.eeb.ucla.edu/test/faculty/nezlin/PhysicalOceanography.htm . I think we should have a picture of a convection current. Here is a link to a similar picture from another educational website: http://www.propertiesofmatter.si.edu/Density_Creates.html WERS logo comes from WERS website: http://www.wers.net/wers-home