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 to 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.
My design includes a light grey coloured roof and exterior to reflect the heat energy from the sunlight. It also will include concrete flooring and brick walls to as they have large amounts of thermal mass.
Insulators are used to minimize transfer of heat energy by conduction, convection and/or radiation. Insulation prevents heat loss in winter and heat gain 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 hot 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.
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.
My design includes all of the windows being double glazed and heavy, close fitting curtains being placed on these windows to reduce the amount of heat energy that is transferred through the windows.
Ventilation is important in summer as it is what will keep the house cool. It is also important as the air-tightness of a house may trap pollutants. Natural ventilation would be caused by windows and opened doors. There are different types of natural ventilation:
My design includes windows and vents placed in various locations to increase ventilation in the house.
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. My design will include very effective seals and weather stripping to cover up any exposed areas that could contribute to unwanted heat loss or gain.
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 direction the window faces affect how much heat the house receives from the sun. The location of windows is very important as they would let larger amounts of heat through it. 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. Covering windows from direct sunlight with eaves and things that overhang will allow the sunlight in the house in winter but out in summer. The diagrams below show how this works.
My design includes windows with eaves and overhanging roof to hep block out the sunlight in summer, when the sun is higher, and let the sunlight in the house in winter, when it is lower. There is also larger windows located in the area that receives the most sunlight to allow the sunlight to be more in the house in winter.
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. The outside of the house design I created will include a lot of carefully placed shrubs and trees around the outside to fully channel the wind that passes through and block out unwanted excess sunlight.