By Shawn Rankin 

Once again, Canadians prepare for the long, dark months spent indoors. Like burrowing animals, we fuss about our homes waiting for the long cold months ahead. We store our lawn furniture, rake our leaves and put the lawn mower away for winter. Snow tires are installed and shovels are taken our of storage. OK, we’re ready for Old Man Winter.  We haven’t forgotten anything… or have we? 

 As Canadians, we  spend just about all of our time indoors during winter months.  Have we prepared our homes for the change of seasons? Colder temperatures make our homes work harder at keeping us comfortable.  Have we done everything we can to ensure a safe energy efficient, healthy heating season?  

Here are some healthy hibernating tips for your home and family.

Cooler climate generally arrives after the leaves have fallen.  Tall deciduous trees that grow close to the home rend to shed their leaves on our roofs and ultimately block our eaves troughs and down spouts.  Ensure your eaves troughs and down spouts are free of debris.

Insect your fireplace damper for operation.  Does your damper (located about 12 inches up your chimney, a door-like mechanism that controls smoke out and cold air in) operate efficiently?  Does it open and close completely?  Is your chimney clean and in good repair?  Have a WETT (Wood Energy Technology Transfer – a non-profit training and education association) certified inspector/cleaner service your chimney, wood fireplace and wood stove annually (www.wetinc.ca).

Are your smoke detectors and carbon monoxide detectors working?  Have you installed new batteries?  The building code now requires operating smoke detectors on each floor of your home. 

Have removed your garden hose and shut off the exterior tap from indoors?  Most homes are equipped with an indoor tap that remains closed during winter while the outdoor tap is left open and drains empty.  Frozen exterior hose spigots are common and expensive to repair.

Inspect all your exhaust and air inlets through wall fittings.  Are bathroom and dryer vents cleans and operating?  Have grass clippings or pollen plugged your make-up air or heat recovery ventilators’ inlet grills?  Clean all vents to ensure smooth operation and required air flow to combustion devices (boilers, furnaces and hot water tanks).  Ensure all direct vent gas fireplace wall fittings are free of leaves and debris. 

Cold winter days restrict the amount of fresh air we are exposed to through open windows.  Healthy hibernators now must rely on exhaust fans and air exchangers to dilute moisture and household generated biological and chemical air quality loads.  Household ventilation and dilution can be simplified by imagining your home is a giant glass fish tank.  The walls of the fish tank are made of magnifying glass and therefore all dust particles (Respirable Suspended Particles – RSPs) are visible.  Over time the occupants of this fish tank generate dust (skin cells, dust mites, dust mite fecal matter, dander, hair, lint, bacteria, viruses and moisture).  Occupant activity may introduce chemicals, soot tobacco smoke and odour.  With our magnifying glass walls we can see the accumulation of these conditions.  The small size of these nano particles (0.3 to10 microns) means they are aerosolized or airborne all day.  A micron is 1/1,000,000of a meter small.  The average human hair is 60 microns in diameter.  Typical household activity and forced air heating systems keep these small particles airborne where they are easy to inhale and difficult to clean.

After a couple of months of this type of dust accumulation, it is easy to imagine the interior of our fish tank as veritable sand storm.  If a sand storm is raging inside our homes and clean air is available outside our homes, we must ventilate.  Ventilation and dilution simply implies mechanically introducing dry clean, fresh air from outside by utilizing a whole house ventilator (HRV), or an exhaust only device (e.g. bath fan).

If we were to mechanically pump all the contaminated air out of our fish tank we would produce less air in the tank compared to outside ( building depressurization).  This is negative pressure would draw clean fresh outdoor air into our tank through leaks and cracks in the tank (wall and roof) assembly.  The small size of these leaks and the large number of leaks and cracks found in the fish tank means we don’t feel cold air on our bodies coming from any specific location.  Fresh air is introduced into our environment by simply exhausting contaminated air from our space.  Exhaust only systems perform the same function as open windows, however the discomfort and cold air sensation are not noticed because the air is infiltrating the space from many small areas.

Whole house ventilation, or a heat recovery ventilator (HRV), exhaust contaminated air from our environment and directs that air through a heat capturing exchanger before exhausting it outdoors.  Fresh clean dry air is then drawn from a healthy exterior location, pumped through that same heat exchanger, warmed up and then “supplied” back to the house. 

Over time exhaust only or heat recovery air exchange systems would eventually dilute or remove all the contaminated air from our tank.  If our mechanical systems were used regularly, then particle/moisture accumulation would be controlled.

If we are going to spend our winter indoors, and we understand the respirable suspended particles accumulation , then we must develop a means of ventilation/diluting our household air.  Exhaust only or HRV mechanical systems to exactly that. 

Most homes are equipped with an exhaust only system (bath fan or range hood directed to outdoors).  The issue then becomes the amount of time that system is in use.  Noisy fans and impatient occupants may discourage fan use.  If a 100 cubic foot per minute (CFM) fan is on for 15 minutes during your shower, you have exhausted (and therefore re-introduced) 1,500 cubic feet of air from you home.  The average Canadian home contains approximately 20,000 cubic feet of air.  Exhausting 1,500 CFM from 20,000 leaves 18,500 CFM of stale air.  Use your exhaust fans long enough to remove enough stale air to benefit the occupant.

Heating system maintenance requires pre-season service and regular inspection. If your house is equipped with an air handling unit (AHU) or a forced air furnace, you may wish to remove RSPs (remember our fish tank) from the household air through the use of filtration.

Modern furnace air filters come in a number of sizes and varsities.  A higher MERV (Minimum Efficiency Reporting Value) filter will  remove smaller particles with greater efficiency.  Too high a filter efficiency may restrict air flow through your furnace and cause mechanical problems.  Too low a furnace filter rating (MERV 2) will not remove RSPs whatsoever.  Contact a certified Heating, Refrigeration and Air Conditioning Institute of Canada (HRAI) furnace/ventilation technician to help choose the most appropriate filter for your home (www.hrai.ca).

Switching your furnace operation from “auto” to “fan on” during winter months will “scrub the air” (furnace air will blow through the filter continuously filtering or scrubbing your home’s air).  Temperature variation from room to room will be decreased with more air mixing throughout the house.

Humidity control and monitoring will reduce the likelihood of condensation forming on cooler building assemblies.  High interior moisture may condense on cooler building surfaces (inside walls and on windows).  If you don’t monitor your temperature and relative humidity, you cannot control it.  Purchase a couple of digital thermal hygrometers (about $25,00 each) and place them around the home.  If the temperature drops or relative humidity climbs above 60% you should accelerate ventilation to dilute and reduce household moisture.  

It is important to weather strip and seal windows and doors.  Houses with excessive air leakage cannot be effectively maintained.  Leaky homes are controlled by the fickle whims of Mother Nature, with temperature, moisture and particle infiltration entering the home environment randomly.

It is better to seal your home as much as possible, rather than to introduce effective controlled ventilation in order to address indoor air quality concerns on your terms, not Mother Nature’s.

During the winter, regular house cleaning is very important to remain healthy.  With window and doors usually closed, the accumulation of house dust and particles requires more flat surface cleaning and maintenance.  Use low VOC (volatile organic compound) soaps and cleaners.  Strong solvents and fragrances add to our environmental load.  Clean your home with low fragrance/chemical content cleaners and a damp mop more frequently to reduce RSPs.  If your home has carpets, vacuum floors and furniture with a true Hepa type vacuum regularly.

It is possible to have a healthy hibernation during the long winter months.  Your home may require some additional maintenance and monitoring.  We cannot rely on open doors and windows for ventilation so we must utilize our mechanical systems to their full potential.  Frequent filter replacement, more diligent housekeeping, and a new found awareness for moisture control will provide your home and family with a safe an healthy environment until spring.

Only 160 days until we can once again open our windows comfortably.  In the mean time, sleep well in your healthy home.

The current meteoric rise in public concern and interest regarding air quality and healthy environments has created an opportunity for industry to market and promote a myriad of diverse products and services. Everything from scented candles and snake oils to ozone generators and air  fresheners are being advertised as the air quality answer to all our healthy home needs.

On average, Canadians spend 80% of time indoors; a great deal of that time is spent in our homes. Controlling the air quality conditions of our work places can be difficult, however improving the home environment simply requires a basic understanding of how the home works. Universally, homes behave as an integrated system: what happens in the basement affects air quality upstairs.

The definition of a healthy home is not about having more. It is about living with less: less humidity and moisture, less chemical, and odours, less particulates and dust. Reducing air quality concerns at home means living with less irritants our bodies’ defense systems must address. Imagine if we were born with a “wheel barrel for environmental sensitivities”, ‘Throughout our lives each person loads their wheel barrel at a different pace (Environmental Exposure). Some people have the capacity to fill a larger wheel barrel of environmental sensitivities (Dose Response). Due to past environmental exposure, other people may not have room in their wheel barrel and may have difficulty handling the environmental burden (Multiple Chemical Sensitivity). The fundamental similarity between all wheel barrels is the universal benefit of environmental load reduction. We must seize every opportunity to reduce air quality and environmental irritants from our homes in an effort to keep our wheel barrel of sensitivities empty. If our environmental load is light, our capacity to shoulder unforeseen air quality exposures is increased.

If we are to adopt the “less load” philosophy to our own homes we must embrace some lifestyle changes that promote healthy environments. We must be able to recognize the conditions that generate poor air quality and we must take the correct steps to improve them. Recognizing these conditions of poor air quality is the first step to improve your environment.

Air quality issues can be divided into two main categories: chemical and biological. Chemical air quality concerns are introduced into your environment typically by the “offgassing” of manufactured products and materials, cleaners, new furniture, construction materials, solvents, dry cleaning, air fresheners, and by-products of combustion. Biological contaminants are generated within the building environment, such as skin cells and fragments, pet dander, dust mites, pollen, bacterial mold and viruses. These types of contaminants thrive in moist, damp environments. By controlling the humidity levels in most homes, the growth of some of these culprits can be minimized.

Once a homeowner has identified potential indoor air quality contaminants in the home, a lifestyle change is required to remove them and subsequently reduce the burden on our personal wheel barrel of environmental sensitivities. We should take every opportunity to reduce exposure to both biological and chemical loads present in our living environments. This load reduction is not completed overnight. Instead, our lifestyle change should incorporate the”less is best” philosophy on a daily basis.

There are four strategies to achieve this change: isolation, separation, ventilation and filtration. The daily application of these strategies will reduce exposure to air quality contaminants, minimize the strain on each person’s wheel barrel of environmental sensitivities, and create a healthier environment.

“Isolation” is a strategy where the term source control applies. If we can identify a situation in the home contributing to poor air quality, the isolation strategy requires complete removal of that condition. For instance, if we’re storing a box containing moldy books, discard them. If we have a leaking pipe adding moisture to our environment, repair it.

“Separation” strategy may be storing strong or foul smelling items in a sealed container. This contains and separates off-gassing or odorous items from the rest of the home. Items such as solvents, cleaners, and paint cans can be stored in a sealed plastic container for future use. Another example of separation is the use of waterproof membranes within the house foundation to prevent moisture or dampness from entering through the exterior walls.

“Ventilation” strategy, which means an exchange of interior air with exterior air, refers to the three types available to most homes. This strategy is a means of diluting the higher concentrations of airborne contaminants and moisture generated inside the living environment. Imagine our home represents a sealed glass aquarium that we inhabit. Inside this aquarium is a constant sandstorm of very small particles we breathe (Respirable Suspended Particulate, -RSP). If we were to create an opening on one side of the aquarium and let fresh clean air in, and we were to place an exhaust fan on the other side of the aquarium blowing out, we would eventually dilute and exhaust the higher levels of RSP found inside the aquarium. This example is how we should perceive the benefits and necessity of a sound ventilation strategy in our own homes.

Effective ventilation can be achieved in three ways. The first is simply to open the windows and introduce fresh air. This is an excellent, easy method of achieving air dilution and air exchange. During cooler months, leaving windows open is no longer reasonable. We now must begin to depend on mechanical means of ventilation. The second means of ventilation relies on “exhaust only” approach to aid exchange. Range hoods and bathroom fans mechanically exhaust air contaminants from inside the home to outside through the fan mechanism.  This exhaust only fan system creates less air in the home and develops a slight negative pressure to the living environment.  Fresh air is re-introduced into the home throught cracks around windows, doors, the foundation and ceiling. This type of exhaust-only ventilation is the most common.  Anew homes have building code standards that govern the size of exhaust-only devices when installed as the principle means of ventilation.  Lastly, the whole house ventilation system is an  integrated system of balanced filtered air in and balanced air out, creating no pressure differential with the home.  These systems can be installed with “heat recovery” technology (HRV)to save the warm air from being exhausted. All three types of ventilation systems perform the same function; to to remove airborne contaminants from inside the home environment, and to dilute the interior air through and exchange with outside air.

The fourth and final air quality improvement strategy should be the use of air filtration. Mechanically forcing household air through a quality furnace filter or filter media device serves the purpose of removing or entrapping airborne particles.  Forced air furnace systems are an ideal way to filter household air on a continuous basis. Switch the furnace fan operation from “Auto” to “On” and have the furnace fan run continuously with a quality filter on your forced air furnace.  If you do not have a forced air furnace, a stand alone HEPA (High Efficiency Particulate Arrestor) filtration device may help.

Although these air quality and healthy home recommendations may seem overwhelming, once you embraced your healthy home lifestyle changes, the benefits are noticed immediately.  Efforts should be make to reduce your environment exposure load and ventilate your home at every convenient opportunity.  If you “isolate” moisture and remove the sources you are aware of, if you “separate” moisture and off-gassing chemical-based roducts; if you ventilate and dilute air quality conditions at every opportunity; and if you filter or scrub the home’s air continuously, you will live in a much healthier environment.

A great source of healthy home and air quality information  can be obtained from the Canada Mortgage and Housing Corporation (CMHC) library located at 700 Montreal Road, Ottawa, Ontario or at their website: www.cmhc-schl.gc.ca.

Shawn Rankin is an accredited Indoor Air Quality Investigator, an  Indoor Environmentalist, and Heating, Ventilation & Air Conditioning (HVAC) Designer, and recognized by the CMHC as a Healthy Home Builder and Designer.  He lectures for the “The Healthy Home Academy”.

Whew… we survived. The periLs of Old Man Winter are behind us. Or are they…”

Early deep record snowfalls, little or no ground frost and warm spring sunshine are recipes for flooded basements, leaking foundations and moist concrete floors. Is your home prepared tor a moist spring and damp summer? Have you removed al the leftover cardboard boxes and winter accumulated junk From your basement?

Every season, spring arrives, melts the snow, and fills our ditches and streams with high water for a week or two.  Snow piles against the house disappear and we begin to store our snow blowers and shovels.  Our thoughts begin to drift off to scenes of summer sunshine and outdoor activities.

Typically, the city storm water managements system (storm sewers, gutters, catch basins and ditches) carry away the winter run-off with few floods or household calamities. ThIs season, heavy snow loads and shallow frost will place our homes in more peril.

Larger water run-off volume and higher ground water tables will mean more wet basements and busy sump pumps. Larger snow banks agaist our foundations add to ground source moisture contnet which builds vapor pressure against our foundation walls. The earth around our foundations that drains slowly, tends to draw moisture into our homes (Mother nature tends to flow from hight to low, moist to dry and warm to cold).

Shallow winter frost typically affects the amount of moisture the earth can absorb vefoe the snow metls and drains water away from our foundations.  More moisture in the ground around our homes increases the water table under our footings and floor dreains.  Cidy homes are connected to the city storm water management system be a perforated drainage pipe (weeping tile of Big “O”) that rests on the outside of the foundation wall, level with the underside of the footing under 8″ of 1/4 clear gravel.  Ground sources moisture, rainfall from the roof and surface drainage water is meant to drain down the foundation wall, work throught the clear gavel, enter the perforated 4″ drainage or weepeing tile then migrate by gravity around your house to the ciyt storm connection and enter the strom water managements system.  Wow lots of stuff hat to happen to keep water out of your basement.

Rural housebolds are not any better off.  Atypical rural ome without connections to the city S.W.M.s. (storm water management system) drains the Big “O” to a hole cut into the basement floor (sump pit).  These sump pits service all the home’s needs for lower level drainage.  Floor drains, condensation pumps, water softeners, air conditioning drains and the entire weeping tile are discharged into this pit to be electrically pumped to a buried pipe exhausting to the ditch at the end of the lane way.  Let’s not begin to talk about heavy March/April snow melts, when the power goes out to these folks.

We can protect the durability and environment of our home if we control our household moisture. Active water leaks or high relative humidity  in our environment can create conditions that foster poor air quality.

Health Canada recommends that homes have a relative humidity between 35 and 45% Dust mite populations increase in moist environments, especially in older carpeting on the concrete basement floors.

Microbiological organisms, such as fungi and bacteria, thrive in moist damp environments, Moisture and cellulose (wood, cardboard boxes, paper goods) are the perfect combination for fungal activity.  It doesn’t take long for these areas to become musty, smelly and unhealthy.

We can avoid these unhealthy situations if we isolate the moisture sources and remove opportunity’s for  bacterial and fungal contamination.  The following time will make a difference.

• Don’t pile snow against the side of your home;

• Ensure that window wells are uncovered and free of leaves and organic materials which can block drainage;

• Enable spring runoff to leave your property by chipping snow and ice away to improve drainage;

• Service and maintain your sump pit.  Inspect pump float levels and operation. Remove all debris and other drainage hoses from the pump float mechanism;

• Install a second sump pump to an independent exhaust hose powered by a different breaker (or fuse). Set pump float adjustment 1″ higher than your primary pump as back-up;

• Install free flowing eaves trough and downspouts with extensions that remove water away from the home.  (There is no point in dumping all your roof water by the corner of your home, with no grade drainage.  Roof water simply seeps down to your weeping tile and into your sump pit or city drain, adding moisture to your environment);

• Keep cardboard, paper, clothes, carpets, hockey equipment, wood, stuffed animals and pillows off concrete floors and away from damp foundation walls;

• Store your items in plastic containers off the damp floor;

• Ventilate your environment during drier cooler months;

• Purchase a digital hygrometer to accurately monitor you environmental conditions;

• Dehumidify damp basements during warmer “muggy” months. Maintain relative humidity levels between 35 to 45%.  Purchase a large enough dehumidifier energy star rated appliance (50-60 pint); and

• Seal/caulk or repair any leaks in the floors and foundation wall assemblies to avoid moisture penetration.

And finally, use your nose.  If you can smell something “earthy” or musty from the storage room or under the carpet, you must deal with it.  Mold will not move out on its own.  Remove the source (moisture and food), wash the area, then keeps things dry.

Indoor air quality conditions can be improved with proactive household maintenance.  Anticipate moist conditions, inspect all pumps and drains, ensure ventilation and dehumidification, and store items off the floor.

Your healthy environment literally begins at home.  Put a spring into your step and into your healthy dry home.