Test Your IQ on IAQ

(And Why We Can’t Stop Talking About Indoor Air Quality)

At steveworks, when we speak with clients about their vision for beautiful, energy-efficient home renovations, we are also talking about indoor air quality (IAQ) and how we can provide a healthier home for families.

So what is indoor air quality?

According to the EPA, “Indoor Air Quality (IAQ) refers to the air quality within and around buildings and structures, especially as it relates to the health and comfort of building occupants.” Studies show that the health effects from indoor air pollutants may be experienced soon after exposure or, possibly, years later.

What causes poor indoor air quality?

Many factors contribute to poor IAQ. Indoor air includes pollutants that penetrate from the outdoors, as well as sources that are unique to the indoor environment. These sources include the following:

  • Human activities within buildings, such as smoking, burning solid and fossil fuels, cooking, and cleaning;
  • Vapors from building and construction materials, equipment, furniture, and rugs; and
  • Biological contaminants, such as mold, viruses, or allergens.

Some common contaminants are listed below (see National Institute of Environmental Health Sciences for more information):

  • Allergens 
  • Asbestos
  • Carbon monoxide 
  • Formaldehyde 
  • Lead 
  • Mold 
  • Pesticides
  • Radon 
  • Smoke, including from gas ranges

How To Improve IAQ

There are several steps we take to improve a home’s indoor-air quality, including testing for pollutants and moisture, eliminating contaminants, remediation (if needed), and improving ventilation. For every home renovation, we start with a pre-construction assessment that includes the following:

  1. Blower door testing to determine how much air is entering or escaping from your home;
  2. Infrared envelope inspections to evaluate building exteriors for facade integrity and energy loss; and 
  3. Air monitoring to collect and measure samples of indoor air to evaluate the status of the air pollutants, including volatile organic compounds (VOCs), carbon dioxide, and radon. (Air monitoring is done by placing devices in your home for a week or so to “sniff” and log the air quality. We then evaluate the results.) 

Airthings Indoor Air Quality Monitor

Once we determine if there are air pollutants, the first step is to eliminate as many of the contaminants as possible. VOC sources may include cleaning products, heating appliances, glues, polishes, waxes, pesticides, personal care products, and the migration of emissions from attached garages. Formaldehyde is one of the most common VOCs and can be found in pressed-wood products (plywood, particle board, paneling), foam insulation, wallpaper and paints, as well as some synthetic fabrics.

We also recommend replacing anything that is burning fossil fuels, including appliances, since they also contribute to poor air quality. Gas stoves are a large culprit. In fact, a 2023 NIH study showed that gas stoves were the primary cause for nearly 13% of childhood asthma; once the gas stoves were replaced with an electric ranges, the children’s asthma resolved. We strongly recommend induction stoves, and our customers love them!  

Ventilation above the stove, even if there is induction, is critical. Recirculating fans are a waste of electricity. Instead, use a vent to the exterior of at least 400 cubic feet per minute (CFM), since all stoves will emit pollutants from food and cooking oil. For more than 400 CFM, make-up air needs to be provided, which is also a good source of fresh air. The makeup air should be placed in a toe kick away from the stove or prep area, or in the ceiling if we use an exhaust mounted in the ceiling, so as not to blow cold air on the “cook.”

Vent To the Exterior Above the Stove

If we find radon, we introduce a mitigation system appropriate to the level of radon and the source. Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil, rock, and water. According to the EPA, radon is the leading cause of lung cancer for nonsmokers and the second leading cause of lung cancer for the general population. There is state and federal funding that can help many homeowners subsidize the cost of utilizing radon mitigation systems.

Radon Mitigation System

One of the most important steps in improving air quality is installing an air ventilation system. We recommend energy recovery ventilators, or ERVs, because they preserve energy. In the summer, warm and humid outside air is pre-cooled and dehumidified via the total energy from the outgoing cool interior air. In the winter, cold and dry outside air is preheated and humidified via the total energy from the outgoing warm interior air. Since less energy is needed for conditioning and ventilation, HVAC equipment can typically be downsized. There are a number of programs that help subsidize the cost of ERVs, including MassSave, which provides an instant $500 discount for qualified ERVs.

Since people spend most of their time indoors, especially during the cold New England months, we continue to talk with homeowners about IAQ to help them understand the risks of indoor contaminants, suggest they test their air quality, and take necessary steps to mitigate air pollutants. It is important to note that the risks of poor IAQ increase as building technologies advance that allow us to build homes and additions that are increasingly airtight. No more counting on those old drafty windows to circulate the air!