A passively designed building uses strategies that maximize energy efficiency and maintain human comfort. The key to the strategy is to maximize the energy that is gained, and minimize the energy that is lost. This type of design can be applied to homes, office buildings, and high-rises. Passive design must have continuous insulation, an airtight envelope, highly insulated windows, heat recovered during ventilation, and solar gain.
Continuous insulation is quickly becoming not only a smart design option, but also a requirement since the 2009 International Energy Conservation Code. Continuous insulation is an uninterrupted envelope of insulation where thermal bridging only occurs at the fasteners. An airtight envelope decreases the amount of air that passes through a space, thus decreasing the need to condition that air. Highly insulated windows will decrease the energy demand for heating and cooling, but the design and placement of windows is even more important. In the northern hemisphere, windows should be placed on the east, south and west facades to maximize the heat from the sun. The use of heat recovery devices decreases the energy demand by pre-heating or pre-cooling the incoming air. Solar gain can be utilized to comfortably heat a space, but if designed incorrectly, a space can become unbearable. The sun is at its lowest angle in the winter, so solar radiation can easily pass through a window and transfer heat into a space. The sun is at its highest angle in the summer, and windows should be shaded to prevent heating the interior of the building.
For the United States, buildings that are designed to use very little energy can be Passive House Certified. The certification is granted by the Passive House Institute US, and is not limited to only houses. The non-profit organization began by rising to the demand of home owners who desired to decrease the energy used in their homes. The value of using an architect is clear as we can guide your next project to accomplish effective passive design – helping our environment, while also helping your energy expenditure as a property owner. JL Architects designs for you, and our shared world; contact us for more information.
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