HOW TO TURN YOUR GLORIFIED TENT INTO A THERMALLY COMFORTABLE HOME
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If you don’t know what “Passive House” means or how it is different from ”passive solar house” you are in good company. Talking to clients I notice there is a bit of confusion what distinguishes them and I explain the main principles and differences. "PASSIVE SOLAR HOUSE" or interchangeable used terms such as “solar house” and “passive design” means the design and construction applies sustainable principles, without reference to the extent of those principles nor reference to actual energetic performance of the house. |
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Passive solar buildings have been around ever since houses were built, seeking out the most comfortable and economical structures as our shelter. For instance, caves and mud huts are “passive” structures as they maintain a comfortable standard temperature throughout the year, that stay warmer during winter and cooler during summer compared to outdoor temperatures. Passive buildings operate on the same principles utilizing passive strategies to reduce the need for mechanical heating and cooling to maintain comfort.
Passive heating is when the building is properly aligned with the sun, using solar radiation as a heating source. As the sun’s energy heats up the space through windows, massing and structure can capture and hold this energy and warm the dwelling.
Passive cooling means natural ventilation, air cooling and shading. Those can greatly reduce the need for mechanical cooling. The use of evaporative and geothermal cooling strategies can also help with keeping the building comfortable. Solar shading like for example properly sized roof overhangs can be used in addition to other passive cooling techniques to minimize solar radiation and glare throughout the summer. One often used natural example is the termite mound. Termite mounds are found in very hot climates, however, because of their design that uses passive cooling through natural ventilation and the stack effect, they maintain a cooler interior temperature so the insects don’t overheat. This is both a massing and passive cooling technique that translates well to human dwellings.
Distribution mechanisms transfer the solar heat from where it is collected and stored to different areas of the house by conduction, convection, and radiation. Conduction occurs when heat moves between two objects that are in direct contact with each other, such as when a sun-heated floor warms your bare feet. Convection is heat transfer through a gas or fluid such as air or water, thermal radiation moves from a warmer surface to a cooler one and is what you feel when you stand next to a wood stove or a sunny window and feel its warmth on your skin.
The term passive solar house can be used from a build that uses a little bit of those principles to “earthships” applying all of them to a great extend. Many also supply their own electricity through solar panels, maximise natural lighting and ventilation and harvest and treat rainwater for household use.
The lived experience of a passive solar house very much depends on the quality of design, the quality of construction and the behavioural patterns of the occupants. If we assume that the designer and builder are skilled and diligent (we’d like to think they all are), then the major variable is the occupant! Many passive solar homes give a “grounded, earthy feel” and work like a dream. However, they come with a certain level of temperature fluctuations, rely on the residents running the building well - opening and closing windows allowing for the required air flow, adjusting shade etc. pending on how your design works - and require a block of land where a proper orientation can be achieved on.
Passive heating is when the building is properly aligned with the sun, using solar radiation as a heating source. As the sun’s energy heats up the space through windows, massing and structure can capture and hold this energy and warm the dwelling.
Passive cooling means natural ventilation, air cooling and shading. Those can greatly reduce the need for mechanical cooling. The use of evaporative and geothermal cooling strategies can also help with keeping the building comfortable. Solar shading like for example properly sized roof overhangs can be used in addition to other passive cooling techniques to minimize solar radiation and glare throughout the summer. One often used natural example is the termite mound. Termite mounds are found in very hot climates, however, because of their design that uses passive cooling through natural ventilation and the stack effect, they maintain a cooler interior temperature so the insects don’t overheat. This is both a massing and passive cooling technique that translates well to human dwellings.
Distribution mechanisms transfer the solar heat from where it is collected and stored to different areas of the house by conduction, convection, and radiation. Conduction occurs when heat moves between two objects that are in direct contact with each other, such as when a sun-heated floor warms your bare feet. Convection is heat transfer through a gas or fluid such as air or water, thermal radiation moves from a warmer surface to a cooler one and is what you feel when you stand next to a wood stove or a sunny window and feel its warmth on your skin.
The term passive solar house can be used from a build that uses a little bit of those principles to “earthships” applying all of them to a great extend. Many also supply their own electricity through solar panels, maximise natural lighting and ventilation and harvest and treat rainwater for household use.
The lived experience of a passive solar house very much depends on the quality of design, the quality of construction and the behavioural patterns of the occupants. If we assume that the designer and builder are skilled and diligent (we’d like to think they all are), then the major variable is the occupant! Many passive solar homes give a “grounded, earthy feel” and work like a dream. However, they come with a certain level of temperature fluctuations, rely on the residents running the building well - opening and closing windows allowing for the required air flow, adjusting shade etc. pending on how your design works - and require a block of land where a proper orientation can be achieved on.
