Our Path to Zero, Part IV: Sustainability and Wellness
One year ago, my husband and I embarked on designing our second house. Our first house, built twenty years ago, was designed with value in mind: we built our house for $100/ SF and sacrificed energy efficiency to do so. For the second house, we have done the opposite and designed a very energy efficient house.
There are different ways to be energy efficient. An 8,000 SF house with a full basement could qualify as an energy efficient or a net-zero energy home if there were enough solar panels to offset the energy consumed by such an architectural behemoth. A passive house achieves energy efficiency using a number of concepts besides the installation of an on-site energy source, such as solar panels.
Net Zero Energy House (NZEB)
The amount of energy consumed is equal or less than the renewable energy provided.
A standard of energy efficiency that reduces the ecological footprint. Typically uses 90% less energy than a standard house.
The criteria that informed the development of our house concept is as follows:
Design a one story compact house.
Minimize disruption to the surrounding landscape by working with the existing site grading and eliminating a basement.
Orient the house north/south and with minimal fenestration on the north side.
Insulate the house to maintain an ideal temperature.
Use a heating and cooling ventilation system that can recover 60-90% of heat and coolant from exhaust air.
Sustainability and Wellness
Because our house will use a fraction of the energy used to heat and cool a traditional house, it will conserve resources and thus be sustainable. Other aspects of the house that qualify it as sustainable will be the materials which, with the exception of the windows, will come from local sources. The house exterior will be finished with a mixture of pine tar and linseed oil, a non-toxic and maintenance free application method used extensively in Scandinavian countries.
Major aspects of the sustainability criteria we used quite fortuitously will promote our health and well-being. The ideas to do this are as follows:
Fresh air: the Energy Recovery Ventilation system we are using to heat and cool will circulate fresh air throughout the house 24/7.
Optimal sunlight exposure: the house will engage the landscape with operable floor to ceiling windows on its south orientation.
A carbon free home: the absence of carbon producing elements (gas stoves and fireplaces) will keep the air free of toxic particulate matter
Moisture control: with superior insulation and waterproofing, the house will inhibit the growth of other toxins such as mold.
The concept of fresh air 24/7 and a carbon free home, have been a huge “aha” moment for me. These features dovetail with a new area of research, the WELL Building Standard, for which I am pursuing certification.
The WELL Building Standard was developed to complement sustainability programs such as LEED (Leadership in Energy and Environmental Design). While sustainability programs like LEED rate buildings or communities that have been put in place, WELL is focused on the people that inhabit the spaces. There are presently 2,160 projects encompassing over 385 million SF applying WELL standards across 51 countries.
WELL is made up of 7 categories:
For the purpose of this blog, let’s visit the first category of air.
Poor quality air has been associated with physical illness and cognitive impairment. 50,000 deaths a year in the United States are attributed to poor air quality. The California Air Resources Board (CARB) has identified about 200 pollutants in air as toxic. WELL encourages clients to test air quality on a regular basis to control and eliminate these contaminants, including:
Volatile organic compound (VOC) particles
Particulate matter 10 (includes mold)
Particulate matter 2.5 (microscopic organic toxins that can be inhaled)
In our passive house design, the guidelines for ensuring clean air are followed and, in many cases, improved upon:
Because we will use a heating and cooling system that uses only fresh air (unlike typical systems which mix exhaust air with fresh), the air quality will be far better and meet or exceed the ventilation and energy standards set by The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE).
We will have fresh air circulating 24 hours, 7 days a week. Most heating and cooling systems stop and restart depending on temperature and humidity readings.
Elimination of items that produce toxic particulate matter (fireplaces and gas cook tops).
Our house is now in construction. When completed, it will almost heat and cool itself. The energy recovery ventilation, insulation, and 4’ wide floor to ceiling operable windows all combine to save energy and ensure clean air.
Air pollution is a huge global problem, one of the biggest challenges our generation and those to follow will face. Laws need to be in place to control the contaminants described above. While our healthy house won’t provide immunity to the problem, it is a start!
We hope it to be an example to other homeowners — an inspiration to build with these energy saving concepts in mind.