Improve the quality of the air in your home
Homes are sealed more tightly than ever. This increases the concentration of a variety of toxic compounds. For example, formaldehyde, a well-established carcinogen, is used in the materials that make up your home, as well as in the furniture and various other objects inside of your home.1 Then you have hormone-disrupting carcinogenic compounds known as perfluoroalkyl substances (PFAS).2 These are commonly used in stain resistant rugs, carpets, and furniture fabric. Then there are numerous other volatile organic compounds (VOCs) that arise during the cooking of food, from cleaning products, from paint on your walls, air fresheners, and personal care products.3 Lastly, you have carbon dioxide, which comes from the occupants in your home. Elevated CO2 levels have been associated with cognitive impairment, disrupted sleep, and a variety of other adverse health effects.456789
The best remedy for all of these issues is to have installed an energy recovery ventilation system or a heat recovery ventilation system as part of your HVAC. These systems bring a constant supply of fresh air into your home in an energy efficient manner. They are best installed at the time the house is built. Unfortunately, they are expensive to retrofit into an already existing home.
Alternatively you can have installed a whole house dehumidifier with fresh air intake. These units have a simpler design that can be attached to your existing HVAC. Some units are able to operate year-round, even when you do not need dehumidification.
Or, of course, you can always just open your windows if the weather is seasonable.
Even if the weather is unseasonable, you can bring in fresh air in an energy efficient manner by doing it very quickly. Place a high powered fan a couple feet inside of an outside doorway or window, blowing the air in your house to the outside. At the same time, open some other windows to allow fresh air to come in, preferably on the other side or your house and/or on a different level. Five or ten minutes is all you will need. You want the fan to be located a couple feet inside of the window or door, in order to take advantage of Bernoulli’s principle:
Do this air exchange a few times per day.
Another tip is to keep your bedroom door open at night while you are sleeping, and/or have your HVAC fan on continuous mode, to help reduce the build-up of CO2.
You can test the quality of the air in your home using a couple different monitors. WapoRich makes a good monitor for formaldehyde and VOCs. Aranet makes a good monitor for CO2. Using these monitors, I found that my tightly-sealed home frequently had high levels of VOCs, and it frequently had CO2 levels above 1300 ppm, peaking at about 2000 ppm in my bedroom at night (you want the level to be no higher than 1000 ppm). Taking the above-described steps significantly improved these numbers, and qualitatively made the air in my home feel much fresher.
Another aspect of air quality is removing dust, pollen, mold, and other particulate matter. A good HEPA filter is all you need. Rather than putting a HEPA filter on your HVAC, which can limit HVAC performance, I prefer a separate stand-alone unit. AirDoctor makes great air purifiers. They are quiet, and they have an accurate sensor that will increase airflow when they detect more particles in the air. When my air purifier starts to cranks up, I know it’s time to dust my house!
Finally, there is the issue of humidity. Ideal indoor humidity is 40-50%. Below this level, and your airways will start to feel dry, and it may increase your risk of airborne infection.10 Above this level, and you will potentially increase the amount of allergenic mites and mold in your home.11 If the humidity in your home is frequently outside of this range, consider investing in a humidifier or dehumidifier.
By the way, the Aranet monitor I mentioned above is great because it not only measures CO2, but also humidity.
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