The whole idea of my design is to take advantage of natural climate to maintain a comfortable temperature indoors.
Conduction – is the transfer of energy from molecule to molecule by direct contact
Convection – is the heat transfer by the mass movement of molecules within gases or liquids. When it is heated and caries the energy away from the source of heat.
Radiation – is energy traveling as waves or particles through space or through a material medium.
Some materials let more heat through than others, like how a thin layer of wood would let more heat through than a thick layer of concrete. Solid brick wall and concrete slabs floors take longer to heat up on hot days and longer to cool down on cold nights.
This is because they provide large amounts of thermal mass. Thermal mass is the ability of a material to absorb and store heat energy. Concrete holds radiant energy and keeps a home warm and dry inside. This can be shown by the diagrams below.
The outside materials of the house that are exposed sunlight would have to be light coloured pigments that reflect the sunlight. Darker colours are better at maintaining heat so a lighter colour will be better at reflecting heat in the warmer seasons. This can also reduce the amount of insulation needed to cool the house. This can be shown in the diagram on the left.
Insulators are used to minimize transfer of heat energy by conduction, convection and/or radiation. Insulation prevents loss by conduction in winter and gain of heat by conduction in summer. It keeps the heat in on cold days, prevents too much heat from getting in on hot days and reduces condensation and dampness. Using insulation in walls and ceilings help to stop heat flow.
An R value (the thermal resistance) measures the ability of insulation to stop the flow of heat. This means that the higher the R value, the better it insulates. Mineral wool batts have an R value of 15. I have used Mineral wool batts in my design (pg) as it is not combustible, holds its shape even in a fire and is very good at keeping hot air in on cold days and the cold air in on cold days.
Insulation is a barrier that minimizes the transfer of heat energy from one material to another by reducing the heat loss or gain. So basically, heat energy can’t properly flow through them.
Glass lets a large amount of heat through it.
The direction the window faces affect how much heat the house receives from the sun. Locating larger windows on the northern side and smaller windows on the southern sides of the house will allow the sun to warm up the house in winter. Placing covering windows from direct sunlight will allow the sun in the house in winter but out in summer.
Window frames also conduct heat, so the use of timber frames would be a good choice as they don’t conduct heat and are an insulator.
Ventilation is important in summer as it is what will keep the house cool. It is also important as the air-tightness of a home may trap pollutants. Natural ventilation would be caused by windows and opened doors. There are different types of natural ventilation:
Draughts are caused by air moving from a warm area to a cold area creating a breeze and contributes to heat loss. Draughts typically come from gaps between frames and walls during construction, gaps around badly fitting windows and doors and the inability to shut off heated areas, chimneys and flues. These problems can be fixed with the use of weather strips on doors to stop air leaks from doors, chimney damper to stop air leaks from the chimney, sealing gaps and cracks in windows to stop air leaks from windows.
Weather stripping can be used on doors to seal the house from any air leaks by creating no gaps between the door and the door frame.
Window seals are also a good way to cover up any potential gaps with the windows.
Shape/Layout of the house
The shape of the house influences heat loss. The house is two stories as it will make the house have a simpler cubic design with less surface area. This will make the house more energy efficient as a simpler layout won’t have as many corners or weak points. The roof is also more likely to be more weather-tight. It will be easier to keep warm as it has less roof surface to lose heat from. The top storey will be warmer because heat rises up through the house. A one-story version of the house I drew the plan for (pg) would be much wider than the original two-story version I drew and would have a much larger concrete foundation area. The concrete foundation area is a prime spot for cold leaks. As the warm air from a heating system rises it pulls cold air in from the bottom. This means that the less cold air leaking means less cold air messing with the air that is being put in from the heating system. The diagrams below show how this works.
Planting plants (like shady trees) will keep the house cool in summer and go against the harsh winds in winter. Planting can also be used to channel breezes through the house, filter strong winds and exclude bad hot or cold winds. The diagrams on the right give a visual representation on how this works.
Trees and shrubs can also provide shading by blocking out direct sunlight in summer. Deciduous trees are good for blocking out sunlight only in summer as they lose their leaves in winter.