The Corona Virus has shaken up our lives. For the first time in a century, we have had to deal with a life threatening virus that is highly contagious and is transmitted through people. This forced businesses to shut down for the last six months, the result of which is many of us now work from home. The pandemic and working from home have made me rethink work life balance.  I have also thought a lot about health: my own health, the health of my family and friends, and the health of the environment. The pandemic hit during the construction of a passive house that my husband Laurence Marner and I designed. Fortunately, construction in Connecticut was allowed to continue during the last six months and we were able to move into our home in June. 

A passive house is by definition a house that uses minimal carbon-free energy. Based on principles developed by the Passive House Institute United States (PSIUS), passive houses rely on orientation and construction methods to vastly limit the amount of energy the house uses.  Passive houses are carbon free (no gas cooktops or fireplaces) and rely on electricity as the only energy source. 

During the construction of our house, I became a WELL (International WELL Building Institute) Accredited Professional. The International WELL Building Institute’s mission is to promote health and wellness for the people who inhabit houses and buildings. While getting accredited, I realized that many of the things we were implementing in our house design dovetailed with WELL Standards, the most significant one being air quality. 

It’s no coincidence that air is the first of the seven categories addressed by WELL. 50,000 deaths a year in the United States are attributed to poor air quality. A space with good air has an abundant quantity of air, as well as technologies to filter contaminants and control humidity which improve the quality of air. Buildings and houses today are substandard when it comes to air quantity and quality. As little as 11-20% of fresh air comes into a building based on the current ASHRAE standards for acceptable indoor air quality. In traditional residential design, as little as 5 – 10% of fresh air comes in from a standard HVAC unit (most houses “leak” and additional air is brought in at windows and other apertures).

The heating and cooling of a passive house is achieved by a method called energy recovery ventilation (ERV). ERV technology brings a constant stream of fresh air into the house 24 hours a day. This equates to an air intake of 70-100 CFM per person, four times the amount of air coming into an office building. In residential and building design, air is also recirculated, whereas in passive house design, all used air is exhausted to the outside.

Air Quantity and Cognitive Function

Dr. Joseph Allen, an associate professor at Harvard and the author of Healthy Buildings: How Indoor Spaces Drive Performance and Productivity, has compelling research showing how increased air into a space dramatically improves cognitive function. 

His COGfx studies have quantified improvement in cognitive function and health when the percentage of fresh air coming into a space is doubled.

Air Quality

The California Air Resources Board (CARB) has identified about 200 pollutants in air as toxic. The WELL building standard encourages clients to test air quality on a regular basis to control and eliminate these contaminants, including:

• Carbon Monoxide

• Volatile Organic Compound (VOC) Particles

• Particulate Matter 10 (includes mold)

• Particulate Matter 2.5 Microns - .3 Microns (microscopic organic toxins that can be inhaled that include mold, bacteria, and dust)

MERV Filtration

A good filter in an HVAC system traps many of these contaminants. The higher the MERV (minimum efficiency reporting value) rating, the more contaminants filtered. The highest rated MERV filters are in the 14-20 range, and are used in hospitals and laboratories and require a powerful air distribution technology not available to most residences and buildings. A snapshot of how residential filters performed can be found below.

Filter rating performance in micrometers:

• MERV 8: 70% 3 - 10, 20% 1 - 3

• MERV 11: 85% 3 - 10, 65% 1 - 3, 20% .3

• MERV 13: 97% 3 - 10, 85% 1 - 3, 50% .3

• MERV 14: 99% 3 - 10, 65% 1 - 3, 75% .3

For reference a human hair is 80 – 100 micrometers.

Humidity Control

Humidity greater than 50% encourages mold growth and dust mites. We have controls in our house to maintain humidity below 50%. 

Tips

1. You don’t have to live in a passive house to control the air quality and quantity in your home.

2. Air quantity can be improved by opening up windows. Of course, there are energy bills to consider when windows are open while energy is being used cooling or heating your house. Figuring out a way to let fresh air in and keep cooling and heating costs down will require some trial and error, but more fresh air will make for healthier occupants.

3. Air quality can be improved several ways, the first by upgrading the filters in your heating and cooling equipment. I recommend a MERV filter rating of 13 but check whether your HVAC system has enough fan power for it (higher filter ratings require considerable fan power to push air through). Filters are available on-line as well as in your local Home Depot. Videos showing how to install filters are also available on the internet.

4. To supplement the air being filtered through your HVAC system, a portable air purifier and humidifier will trap the pollutants that you bring in from outside. These devices will purify and humidify about 400 square feet of space and use the highest rated MERV filters (rated 14 and known as HEPA), as well as ultraviolet light to purify the air. 

5. Vacuum cleaners that use HEPA filtration are now on the market. Our Dyson HEPA filter vacuum is cordless, lightweight, and cleans better than all the products I have used before.

6. Last but certainly not least are plants. The National Aeronautics and Space Administration (NASA) experimented with plants as a way to purify air in space stations and came up with a list of recommended plants. Our biggest plant, a Philodendron, is included on their list. 

Once you’ve made some adjustments to your home, you can reassure yourself that your strategies are working with a number of monitoring devices on the market. The device we chose is manufactured by Awair, and monitors the pollutants and microbes described here, as well as temperature and humidity. 

If there is a silver lining in this pandemic, it is the research response by companies such as Dyson and Awair that have quickly brought to market affordable ways to make healthier spaces in the home. The pandemic has also been a wakeup call for corporate America to make healthier work environments for their employees. Increased well-being and health, whether it be working at home, in the office, or a combination of both, is well within your reach, whether it be large or small interventions.

House Update

Passive houses depend on sunlight for heat; the beams in the ceiling extend outside and make sunshade to limit sunlight in the hottest months of the year.