By Shiva Jayabalan, Manas Sesetti and Labib Khan We all face a large problem during summer: keeping our house cool. With the sweltering weather, which Australia provides, keeping our houses at a modest temperature can be a pain. This booklet is a guide as to how to beat the heat this summer. There are many ways in which we can keep our houses cool during the warmer months in the year. None of these methods are difficult to execute either, so performing these procedures will in fact not be inconvenient. Even though many people rely on air conditioning to keep their houses cool, this can be expensive and very energy inefficient. By following the tips mentioned below, you will be able to substantially reduce your need for air conditioning in your house. R o s s m o y n e S e n i o r H i g h S c h o o l 9 S C I H _ 1 2 0 1 5

C o o l H o u s e A s s i g n m e n t

Cool House Aim: To design a house that keeps cool in summer and limits heat.

Introduction: Heat can enter a house in many ways- through the windows, roof, walls, the doors, etc. This can be very inconvenient for us because in a country as hot as Australia, we need to try and keep our houses cool. Heat enters a house through a mixture of conduction, convection and radiation- radiation from the sun, conduction from the air outside to the air inside and convection through lack of ventilation in roofs. In a similar manner, heat can exit a house just as easily. Using a variety of methods, which are explained below, can prevent heat.

DESIGN, MATERIALS, LAYOUT AND REASONS FOR CHOICE

Orientation The orientation and shading of your house is in fact a very important factor of its temperature. Your house should be orientated such that the longer axis of your house is facing in the East to West direction. This will minimize the sidewall area exposed to the morning and evening sun (since the sun rises in the east and sets in the west). Make sure that that living areas and rooms that you spend the most time in should be north facing. Verandahs and shading tools, as well as natural factors that dont cost a thing such as trees and large shrubs, can be used to shade the walls and the windows of your house, particularly in the east and west directions because that is where most of the sunlight will be coming from. For additional shade, you should also tint any windows which are exposed to the sun, because this will also help keep out the heat. Eaves over north facing windows can keep unwanted sun in summer and let in the suns heat in summer as well.

Ventilation Ventilation is also important since the provision of fresh air to a house a significant part of keeping a house cool. If there are less hallways (and other cramped up) areas, and there are not many internal walls, it would be easier for fresh air to transport in between rooms, so there will be good cross ventilation. Having at least two doors in every room can also increase cross ventilation. If there are wide opening doors and windows, this will also assist with the ventilation. Ventilation in the roofs is of course necessary, and all doors and windows should be positioned such that it would be easy for them to trap winds, which are coming from the northeasterly and southeasterly directions.

Materials Building materials and colours should also be taken into consideration when attempting to keep a house cool. If the building is lightweight, this is preferred because they cool very quickly at night. The roofs and walls should have light colours (the lighter the better) as light colours reflect heat much better than dark colours, which absorb heat. Most importantly, however, the paints, which you use to colour your roof and walls, should have low emissions, because this will be much healthier for your family. Even though it will be slightly more expensive, it will not be much different in terms of price and safety should be valued over money anyway. Limit the number of glass in your home as it can make your house very hot in summer. Constrain the amount of glass windows on the east and west side of your home.

Insulation Insulation is very important because it is what will be the most significant in terms of how much heat will enter your house. Your roof should have reflective bulk and foil insulation, in order to reflect heat and keep your house cool. Similarly, your walls should also be insulated with foil and bulk insulation to substantially reduce the amount of heat entering your house.

Outdoor Living Rooms

Almost everybody has outdoor living rooms. These also need to be kept cool during summer. To do this, try to make them well ventilated, weather proof and centrally located. Outdoor areas should also be linked to internal living areas using sliding doors to make the indoors cooler with fresh outdoor air. Between the pavilions, there should also be courtyard spaces so you can have useable outdoor areas, and to have access for breezes to enter the home. Use of Energy

In general, you should also make sure that you use as little energy as possible. Make sure your lighting is 100% energy efficient, and you use energy efficient appliances to save running costs. Solar power and hot water should also be used to have free energy from the sun; a renewable source of energy. LED lights save as much energy as fluorescent lights and last up to three times longer but the best option is natural lighting in the home which saves energy and money.

Garden Your garden should also be able to help keep the heat out. It should compliment your house design and vegetation should be incorporated to shade your house and to help breezes make their way into rooms. You should also have native plants in the garden to attract native fauna and to reduce the need for watering. To save water, use a rainwater tank to provide water for the pool and garden, keeping your house cool. In addition to keeping the heat out, a veggie garden can be used to provide your family with fresh fruit and vegetables, for free. Trees and shrubs can be used to block out the harsh morning and evening sun in the west and easterly directions (sunrise and sunset). In the end, the energy star rating of your home is what defines how well it keeps the heat out. Talk to your builder or designer to identify how you can use the features mentioned above to increase the energy star rating of your home.

Sketch up Model

NOTE: THERE WAS A ROOF COLOUR ERROR SO THE REAL ROOF COLOUR IS A WHITISH-CREAMISH COLOUR!

The roof colour is white (wrongly shown on the picture above) and heavily helps reflect suns light, which stop a lot of heat from entering the house (radiation heat). The roof has aluminum foil and many other materials which reflect sunlight (stops radiation heat) and stop heat from being conducted into the house.

Ventilation

Evaluation Overall, everything in our Cool House Assignment went to plan; it was a solid effort. We all worked together to provide a more than adequate finished product: Shiva and Manas worked on the written sections and Labib worked on the designing of our house. We did quite a few things well. Our report on the features of our house was detailed and contained substantial information with regards to every aspect of our house which contributed to it preventing heat. Additionally, every heat preventing aspect in our house was justified as to why we used it and how it prevents heat from entering our house. The house design, which was done on a Sketch Up model was also very detailed and it, was very accurate and consistent with our description of the house. We also considered many additional features on our house, which could help it prevent heat from entering; such as the insulation of our house. There were also some things, which we could have done better. We feel that we should have spent more time on the report of our houses features, rather than doing it quickly and immediately before we started the design of our house. Our house design also would have been improved if we looked at a broader range of sources on the Internet; and not just two sources and our general knowledge. Cost would not really have been an issue with our house; perhaps it would be slightly more expensive than it would have been without the heat preventing features, but it would not have made much of a difference. Our Cool House Assignment was a decent effort and we have learnt tips and tricks to save heat in our houses too.