Renovating and Indoor Air Quality

November 13th 2009
Renovating and Indoor Air Quality

As Canadians spend more time inside during the winter months with their furnaces running and windows sealed up, addressing healthy indoor air quality is crucial to keeping our homes healthy. Through our efforts to be energy efficient, today's homes are built to seal the heat in and keep the cool air out. Even if you don't live in a new home, you likely spent time weather stripping doors, caulking windows and upgrading insulation in walls and attics. As a result, you've succeeded to cut your heating bills, however at the same time you have made it more difficult for fresh air to circulate through your home and allow the stale air to move out. From the products we use to the way we approach upgrading our homes there are some considerations to keep in mind that can impact the air quality inside our homes.

One of the biggest issues that impact air quality is excess moisture usually caused from insufficient ventilation. Condensation on windows, peeling paint and musty smells are all indications of an indoor air quality problem. It's actually a sign of high humidity in the house. When excessive moisture or water accumulates, this creates the perfect conditions for mold spores, particularly if the moisture problem remains un-addressed. Humidity is measured by a hygrometer which can be obtained from hardware stores. Keep the humidity in your house below 50%. Ideal humidity is 30% - 40%. The way to control this is by increasing ventilation to reduce indoor moisture caused by daily household activities such as cooking, showering and bathing.

Adequate ventilation promotes a healthier home environment by circulating and renewing the air removing pollutants and excess humidity as well, it protects the structure of your home by removing excessive moisture. The "least" energy efficient way to ventilate in the winter months is through open doors, windows and other non air tight openings known as drafts. There is wide range of more effective devices to address ventilation. To start, use kitchen and bathroom exhaust fans that exhaust directly to the outside. Run your bathroom fan at least one hour after each shower and bath. Install a dehumidistat, a device to operate a ventilation system such as a bathroom fan, furnace motor or an HRV (heat recovery ventilation.) The settings of this unit is determined by the outside air temperature.

Consider installing a whole house ventilation system. A Heat Recovery Ventilators "HRV" or "Air to Air Exchanger" allows fresh air to enter while exhausting an equal amount of stale air and recovering the heat from the exhaust side using it to warm up the cooler fresher air coming in. This is by far the most economical way of improving the indoor air quality in the house while reducing energy consumption. Air is filtered before being redistributed in the house. If you suffer from allergies and asthma you can add a HEPA filtration system to the HRV. Check out

Air Filtration - Filtering out pollutants is what cleans indoor air and maximizes indoor air quality. Check and clean or replace your furnace filters with a good quality filter on a monthly basis. Check the M.E.R.V. rating (Minimum Efficiency Reporting Value) This Furnace Air Filter comparison provides an overall review of the efficiency of commonly used furnace air filters. Another product available is The Ultimate Vent which replaces the fresh air intake vent on the outside of your home, designed to filter out insects, dust and air pollutants. Go to

Have your heating ducts cleaned professionally after a major renovation or after new home construction as saw dust etc. do get in the heating ducts. It's ideal to have your heating ducts cleaned when you are replacing your furnace as well.

Have a qualified technician inspect and clean fuel-burning appliances yearly, to ensure they are in good working order and that they are properly sealed and vented. A working Carbon Monoxide detector is essential. Carbon monoxide is an odorless gas that is produced by a number of common household sources, including wood or gas fireplaces, gas furnaces and gas appliances. Carbon monoxide detectors warn you when the level of the gas in the air has become dangerous.

Whether you are installing new windows or upgrading your heating system, changing one item can cause issues elsewhere if your home's ventilation is not adjusted and could cause excess moisture and condensation problems. Your home must always be dealt with as a system.

There are several reasons why you may have air quality issues and there are a range of corrective measures. There may be ongoing health concerns with allergies and asthma triggered by dust or molds or perhaps the off gassing of new paint, furniture or flooring so it's important to choose products and materials wisely that won't contribute to the problem. In older homes moisture could be coming up through basements. If after all other measures are taken and there is still concern such as ongoing odors or excess condensation on walls and windows you may require a specially trained independent air quality inspectors or basement and foundation specialist to help diagnose the problem and determine corrective measures. For more information on these services contact Shell Busey's Home Services Referral Network at 1-888-266-8806 or