Indoor Air Quality: Is your home safe?
Make sure your home air is safe.
Good air quality affects the health and comfort of those who live with you. How can you minimize the risk of health problems?
How do you ensure optimum home air quality?
You must control indoor pollutants in the home. As well, you must control the outdoor pollutants that enter the house. Third, you must make sure the moisture in your home is appropriate.
Let’s review these three elements one at a time.
Optimal air quality is achieved when you have proper:
- Air exchange
- Moisture control
1. Proper Air Exchange
Your home air quality is affected by pollutants both inside and outside the home.
In-home air pollutants
Current air quality inside your home is affected by outgassing paints, wood stains, varnishes, household cleaners, and furniture chemicals (eg, fire retardants). They are all classified as “Volatile Organic Compounds'” or VOC’s for short.
Natural gas or propane used in the home for heating and cooking purposes can also be a culprit. When burned, such gasses produce carbon monoxide (CO2). To test for levels of this dangerous gas, a Combustion Appliance Zone test (CAZ test) is performed to check for leaks, CO2 levels, and proper exhaustion of the gas.
Outdoor air pollutants
For every cubic foot of air which escapes from your home, another cubic foot of air is drawn back in. Natural air exchanges through your basement, crawl space and attic can introduce outside air pollutants contaminating your indoor air.
From the attic – If this air is drawn in from or through the attic, it can pass by dirty attic “dust” and insulation. Voila! You’ve introduced uncleaned (unfiltered) air in the home.
From the base of your home – Air is also drawn into your home from the base of your home. Here we are referring to airflow in the basement, subfloor and/or crawlspace. There are several possible pollutants that enter this way, including dusty air and, soil gasses (eg, radon, methane, others). Other outdoor pollutants, such as smog, smoke, pesticides and allergens (such as pollen), are also possible culprits.
When outdoor air enters the home without any controls, pollutants can accumulate in the home at levels that pose health and comfort problems. Knowing your home’s current air leakage rate and where these air leaks are occurring is the first step to truly controlling your home’s air quality. Here a blower door test and infrared scanning are used to test for such conditions.
2. Proper Mechanical Ventilation
It is important to have “fresh” or outside air introduced and exchanged, but controlled at the proper rate. The incoming air must be cleaned to ensure outside pollutants are not introduced into your home. Appropriate filtration will ensure this. Heat or energy recovery during the exchange is also key to not losing costly “conditioned” air.
To know whether you need to fix this situation, you must first measure the ‘air tightness’ of your home. This is done by using a blower door test to quantify air flow. Once determined, adjustments can be made to achieve the recommended level of air quality.
Proper mechanical ventilation involves a true air “exchange” at the appropriate rate. Most homes don’t have mechanical ventilation. An Energy Recovery Ventilator (ERV) or a Heat Recovery Ventilator (HRV) may help. Some homes may need such a device, yet homeowners don’t realize how unhealthy it can be without one. To learn more, view the brochure about Energy Recovery Ventilators.
3. Proper Moisture Control
If the moisture level (humidity) in your home is more than 35 percent, your home could be headed for trouble too. Moist conditions can lead to mold and mildew, which are unhealthy.
Wet spots in the walls or floors can cause problems, whether you can see them or not. While some types of mold are annoying or can produce allergens, some kinds are toxic. An infrared scan helps detect hidden moisture in the home.
If needed, humidifiers at the furnace will ensure the desired amount of moisture or humidity will be present in the home. In some climates, air conditioners are needed.
"Seal Tight. Ventilate Right."
This industry phrase means that a home should technically be as airtight as possible. This is accomplished by various tests and then adjustments to achieve this excellent air quality in your home. In other words, it is a science.
So, how do you determine if your home air quality is not optimal?
You can order any of these tests for a specific problem. But a home energy audit, which includes all the tests mentioned above (and more), can pinpoint your home’s current air quality, plus provide recommendations on exactly what to do about it.