House Materials And TechnologyBy Kate Kodagoda

Glass and windows• Triple glaze windows Triple glazed windows consist of three sheets of glass, each separated by an air gap. The air gaps provides

insulating layers between the glass, which slow down heat loss, keep in cool air in summer and keep hot air out, they also reduce the opportunity for condensation to form.

Using the right type of window frame is also important as heat and cool can escape through frames as well as windows. Normal window frames are generally manufactured from low conductivity materials, like from softwood, hardwood, glass fibre and composites. Insulated hollow frames can further reduce heat loss and improve comfort.

Low Emissivity Glass (Low-E Glass) The windows are coated with a very thin layer of metallic coating on one surface. To protect it from wear,

the coated surface is placed on the outer face of the inner pane in a triple glazing layer. The coating allows heat from the sun to enter the house but significantly reduces heat loss by reflecting radiant heat back into the house.

Insulated hollow frames

Triple panes of glass

Air gaps between glass

Low E glass surface

blinds and shades

• Honeycomb cell shades Cellular Shades, also known as Honeycomb Shades are made of a solid fabric that stacks like an accordion.

If you turn the shades sideways, they look like a honeycomb. The air pockets make cellular blinds very energy efficient.

Honeycomb air pocket

Bricks I have chosen a new form of brick which is made by pressurizing by-products of coal-power plants. While

making cement for concrete bricks spew's thousands of pounds of poisonous mercury into the air each year, this eco-friendly brick, uses a coal-power plants’ waste product - fly ash - which otherwise would fester in a landfill. The brick solidifies under pressure and not extreme heat, so manufacturing them saves energy and reduces costs by at least 20 percent, and with the bricks being moulded, they’re smoother and more uniform, this also reduces bricklaying time as well as labour.

Solar panels

The roof of the house is lined with Solar photovoltaic panels, or solar pv for short, this is a technology which converts daylight into electrical power. It uses energy from the sun to create electricity which transfers into the house’s electrical grid, this solar electricity will then operate electrical appliances and lighting.

These solar panels do not rely on sunlight but daylight, which means they are capable of generating electricity on a cloudy day. Using solar panels saves money and energy because you are not paying for all your electricity and it means less coal is burned.

Solar roof tiles

Solar tiles operate on the same principle as solar pv panels.

Water

• Harvesting rainwater for drinking and household usage The house has a pitched roof which provides a suitable rainwater catchment area and the existing

rainwater pipes and gutters will act as the harvesting system. It is preferable to collect the rainwater that falls onto a house roof.

From the roof the water runs through the gutters and underground into an underground water storage tank, the water tank is stored underground because lower light and temperature levels will reduce bacteria growth. Simple filtration without using chemicals or disinfectants is sufficient to allow rainwater to be used for flushing toilets and filling up washing machines.

Collected rainwater can be used for drinking as there is a UV sterilisation unit; the unit is switched on permanently and uses c. 40 watts. This unit will need two filters such as a sand filter, before the water reaches it.

There is a back-up mains supply that will operate automatically when the underground storage tank runs low.

Water tank

Grey waterThe grey water collected from the washbasin, showers, bath and dishwasher is pumped into a tank by an internal waste water drainage system. The water is then treated with a mixture of physical treatment( removing solid debris) and biological treatment( using chemicals) known as bio-mechanical treatment. Bio-mechanical treatment works by filtering solid debris from the tank and then using bacteria to remove organic material (contamination) from wastewater. Once this process is complete the water is fine to use on the garden. Although the bio-mechanical method is expensive, it uses less chemicals, which is better for the environment and the water can be kept in the tank for a longer amount of time.

Grey water tank

sewage

• A Bio-Septic tank

The Bio-Septic process begins when all wastewater from the toilets and bathroom drains into the septic tank.

The solid waste settles in the septic tank and naturally occurring anaerobic bacteria slowly break it down.The wastewater overflows into the aeration tank where air is diffused into two separate aeration chambers to create aerobic bacteria. These quick acting bacteria reduce the sewage to carbon dioxide and water. Because aerobic bacteria breathe oxygen there is no odour. Last, a small amount of chlorine is added to kill any pathogens that have survived the aeration process. The treated water is then suitable to irrigate the garden and any leftover sludge or grime is slowly eaten away by bacteria. Using a bio-septic tank prevents waste from contaminating rivers and oceans, which is good for the marine life and for us.

Garden plants: The Garden consists of plants and trees which need very little water to grow. I have also used artificial

grass made from recycled products and plastics, so there is no need for watering. All the trees and plants that have been chosen are found in Australia and are attractive as well as fairly self-sufficient.

Insulation

The walls floors and ceiling are insulated with a product called Cellulose Fibre, Cellulose is made from old newspapers and other waste paper.

How is it made? Cellulose Fibre is made using recycled shredded paper, treated with borax for flammability and smoulder

resistance. The borax also makes the insulation unattractive to vermin and resistant to insects, fungus and dry rot.

Recycled cellulose insulation has a low embodied energy compared to rock wool and glass wool insulation and, when removed from a building, it may be used again or disposed of safely without creating toxic waste.

Cellulose does not cause skin irritations and the thermal performance of cellulose insulation compares favourably to other types of insulation. These results are similar to those for glass wool or rock wool.

Water and energy saving appliances

• Water saving shower heads: Satin jet Genesis Wall Shower on Upswept Arm Satin jet uses Twin- jet technology and has been internationally awarded for its unique advancement in the delivery of less water while still feeling generous in its water pressure and spray. This shower head only uses between 7.5 and 9 L of water per minute. Ordinary full-flow showers use 22L per minute.

• Dual flush toilet: 4 star rating, can save up to 25,000ltrs of water a year

• Water saving dishwasher: the house is installed with a 5 star energy and water saving dishwasher.

• Water saving taps: water conserving taps that use ceramic disc (CD) cartridge technology that are resistant to scratches and do not leak like ordinary washered taps.

Lighting

The house is installed with Energy efficient light bulbs( Compact Fluorescent lamps) or CFL for short. CFLs use less power to provide the same amount of light as an incandescent lamp, reducing energy consumption and the environmental effects from power generation. CFLs last up to 6-15 times longer than incandescent light bulbs and 75% less energy in their lifespan.

Heating and Cooling The heating and cooling is controlled by a heat pump system. Heat pumps offer an energy-efficient

alternative to furnaces and air conditioners. Like a refrigerator, heat pumps use electricity to move heat from a cool space into a warm space, making the cool space cooler and the warm space warmer. During the heating season, heat pumps move heat from the cool outdoors into your warm house; during the cooling season, heat pumps move heat from your cool house into the warm outdoors. Because they move heat rather than generate heat, heat pumps can provide up to 4 times the amount of energy they consume.

The most common type of heat pump is the air-source heat pump, which transfers heat between your house and the outside air. A heat pump can trim the amount of electricity you use for heating by as much as 30%–40%. High-efficiency heat pumps also dehumidify better than standard central air conditioners, resulting in less energy usage and more cooling comfort in summer months.

Heat pump system