As we design new custom homes and renovate existing homes into dream homes, we have to think about indoor air quality issues. Studies have shown that we spend 90% of our time indoors. Scientists have reported that warming temperatures have a direct impact on seasonal allergies such as tree pollen. I know my seasonal allergies are impacting me daily! We have also seen a rise in airborne viruses. Add the pollen and viruses together with building code requirements for tighter and more energy efficiency and you get indoor air quality challenges in your home.
Filters
There are ways to design better systems that not only filter out pollen but clean the air in your home to a point where you will get sick less often. The first line of defense is a high-efficiency air filter for your heating and cooling system. This filter should have a MERV 13 or higher rating with pleats that catch allergens like pollen, dust mites, and pet dander. Then you need to remember to replace the filter on a regular basis. I use a 5” pleated filter in my system at home which should be changed every 6 months. Many filters require a 1 – 3 month change if they are not as robust as a 5” pleated option.
In addition to a quality filter, you may think about installing an air purification system on your return duct, such as a UV germicidal lamp. These systems will kill viruses that land on the coils of your HVAC system.
Humidity
Humidity control inside your home is also a key feature to keeping mold from growing. This is not only done with your air conditioning system but could also include a dehumidifier. Other impacts to indoor humidity are insulation in your thermal envelope of the home, the water management system on the exterior of the walls and roof, and the source of fresh air. Keeping humidity below 50% reduces the chances of mold growth.
HVAC System
A quality HVAC (Heating, Ventilation, and Air Conditioning) system will include ducts and vents that have 10% or less air leakage before they get to the room they are intended to heat and cool. This is not the normal standard air leakage I see in ductwork for many existing homes. You may also consider adding ventilation to your HVAC system if the house is tight enough to need it. This can also be done in the return duct using an ERV (Energy Recovery Ventilator).
Keeping your HVAC system running efficiently can also contribute to better indoor air quality. This regular maintenance will verify that all systems are functioning properly. The company doing this work will also look at preventative measures to keep your system functioning properly.
Materials
Thinking through the materials inside your home is another important indoor air quality design strategy. You will want to make sure that you don’t add anything that has toxic off-gassing once installed. There are many glues, paints, and stains that no longer have VOC’s. Using hypoallergenic furnishings and carpets is also recommended. Paying attention to your ductwork install is also important. Masking off ducts during construction keeps them clean prior to startup.
If you are like me – itchy eyes, running nose, and a seasonal cough – you will want to do everything you can to improve your indoor air quality. It will pay off in less sick days, more energy, and a clearer head.
