It’s summer! Fresh breezes are blowing through the open windows and clearing out all those indoor air pollutants that built up over the winter months, right? Only, maybe not. If you’re in a traditionally heated and cooled home in California, you’re probably cranking up the air conditioning right about now. Worse, you’re keeping the doors and windows firmly closed against California’s terrible smog and wildfire season.

Unfortunately, summer months can have a worsening effect on indoor air quality if you’re using an AC unit. Beating the summer heat with air conditioning causes high humidity at the unit site, increasing the chance of mold. Closed windows and doors mean toxic chemicals, dust, and other airborne particles are stuck inside and accumulating from poor ventilation.

Volatile organic compounds (VOCs) and indoor air pollutants that can build up in your home and diminish your indoor air quality over the summer come from:

• Formaldehyde and other toxic chemicals common in traditional building materials (including flooring, carpet, and cabinetry), paint and furniture
• Synthetic cleaning and fragrance products
• Dry cleaned clothing and other textiles

Worse news, in California, a spike in ground-level ozone levels during the summer has given us the dubious honor of holding all the top spots on “worst air in the country” lists. Santa Clara gets an F rating on air quality.  So, even if you wanted to open up some windows to ventilate your house and reduce the concentration of indoor air pollutants, you wouldn’t be in much better shape.

Ozone levels and your indoor air quality

Ozone in our atmosphere is a good thing. It acts as a shield, filtering harmful ultraviolet radiation from reaching Earth’s surface. This is called “stratospheric” ozone. Closer to the surface, ground-level or “tropospheric” ozone is a harmful pollutant generally referred to as smog.

Ground-level ozone is created when VOCs and nitrogen oxides interact in hot, sunny environments. As human activities like burning fossil fuels and other types of energy consumption diminish our stratospheric ozone levels, in turn, they increase our tropospheric ones. The rise in ozone around us is the cause of health dangers like lung disease, asthma, and other respiratory illnesses.

Ironically, ionic air purifiers designed to mitigate indoor air pollutants like VOCs are actually contributing to the increase in ozone. A better way to manage indoor air pollutants during the summer months is through a combination of source control, ventilation, and filtration.

Reduce pollutants and cool your home naturally

Passive house principles can reduce or eliminate the need to run unhealthy AC units, keep outdoor air pollution from entering the home in the first place, and thoroughly filter and refresh the indoor air on a regular basis. At Clarum, our modern, custom homes are built with the passive house techniques and principles designed to prioritize health and comfort. Indoor air quality is assured through eliminating the causes of indoor pollution (source control), properly ventilating a home in all seasons (ventilation) and filtering out toxins that find their way into the house through other means (filtration).

Source control: Stay cool naturally so you won’t need to run unhealthy AC systems

• Clarum’s passive and high-performance homes are oriented to reduce direct sunlight exposure during the summer months, including building and design techniques like cantilevered roofs and over-hangs, screens and external sun blinds.
• Clarum’s whole-house approach to design utilizes materials that are high in thermal mass. Thick walls made from SIP panels, cross-laminated timber (CLT), wood fiber insulation, rammed earth, stone and concrete not only look modern and stylish but absorb heat when it’s hot and release heat when it’s cold.
• An air-tight structure is the foundation of a high-performance and passive home. By avoiding gaps in the structure, utilizing the best in efficient windows and doors, and minding incidences of thermal bridging, Clarum’s custom homes stay cool while temperatures rise.

Ventilation: Maintaining energy efficiency while minimizing indoor air pollutants

• Clarum’s custom home designs deploy the principle of stack ventilation to harness the fluctuation of air pressure, keeping stale, warm air circulating up and out, while cooler, fresh air enters in the lower living areas.
• Super insulated and high-performance windows don’t conduct heat, reflecting away summer heat while still allowing sunshine and light to enter the home. When you want to open windows, passive dwellings often include flexible options to open in a variety of ways to increase ventilation.
• Clarum uses the Zehnder Heat Recovery Ventilation (HRV) system to heat, cool, and distribute fresh, clean air throughout our custom homes. The system improves indoor air quality by replacing stale air with fresh air nine times per day. Plus, it runs on only 16 watts of energy, substantially reducing your energy bills and your contribution to Ozone-increasing pollution.

Filtration: When the air outside is more polluted than the air inside

• The HRV system in a passive home isolates and removes odors and contaminants through pressure control and filtration, exhausting polluted indoor air outside. Ozone and activated carbon.
• The air being brought into a passive home is highly filtered through the HRV system’s filters. At Clarum, we use MERV 13 filters layered with activated carbon, one of the most effective processes for removing ozone from the air.

At Clarum our modern custom homes are built with the most innovative and sustainable HVAC systems and building materials. Our attention to these details means your family will enjoy fresh, healthy and comfortable air, no matter what the smog advisory is this summer.

To learn more about our commitment to modern, sustainable design and toxin-free living, please call us at 650.322.7069.