Energy-Efficient and Natural House Construction: Working with the Sun, Earth and Air
Jun 01, 2016 07:22AM
By Marilee Burrell
Natural Building Project by Lou Levy Construction
What is the basis of an energy-efficient house, addition or alteration project? Two primary conditions constitute this type of construction.
The first is that the completed project uses minimal external utility resources for heating and cooling. This goal can be achieved by doubling or tripling the amount of insulation around the envelope of the building or addition, and by using triple-glazed windows. High-efficiency appliances and lighting also can be used to minimize electricity consumption.
The second is that the house is built air-tight and sealed with state-of-the-art air and vapor control barriers that still allow the walls to breathe—that is, they allow air to filter through the building’s shell.
The project becomes a natural house, addition or alteration when we incorporate design elements focusing on nature and sustainability. The idea is to create an environment within the living space that is similar to the feeling we have when standing in the woods or on the edge of a stream or lake.
Three elements are key to natural construction: sun, earth and air.
Passive solar design uses the sun as a heat source, with proper roof overhangs to prevent overheating. This is accomplished by incorporating an interior thermal mass—stone or tile on concrete, a masonry wall or fireplace, a water feature (such as an interior pond, a waterfall or water wall, or a wall of enclosed water), or a crushed rock mass under the slab—with an air or hydronic transfer system. Solar-electric hot water and heating systems can also be incorporated.
The idea is to create an environment within the living space that is similar to the feeling we have when standing in the woods or on the edge of a stream or lake.
The earth is used to create flow in the design from the interior to the exterior environment. The ambient temperature of the earth (a constant 52 degrees below the frost line) has a natural tempering effect in the winter and cooling effect in the summer. The benefits from this effect can be incorporated by direct ambient gain or by a transfer system running through the thermal mass.
Natural ventilation is achieved by design and placement of active windows and clerestories to use what is known as “the stack effect.” In simple terms, hot air rises. So creating cross-ventilation by opening windows on the first and second floors along with a clerestory or skylights means the air will naturally ventilate.
During the winter months and the hotter days of summer, supplemental use of a central ventilation system with a heat exchanger can exhaust stale air and bring in fresh, tempered air.
Other aspects of a natural interior environment are the use of nontoxic building materials, finishes and furniture as well as geological and electromagnetic mitigation.
A house or addition built correctly along these parameters needs only minimal heating or cooling backup, such as a high-efficiency gas boiler or even a simple electric water heating system supporting a radiant floor or baseboard system.
Nature, efficiency and sustainability—a blend of designs that are age-old, as well as state-of-the-art construction, designs and products—are the keys to a balanced ecological environment that we call home.
For more information, contact Lou Levy Construction at 914.804.4145 or visit LouLevyConstruction.com.