Moisture Generated in the House can come from many sources - people, pets, cooking, showering, fish tanks, drying cloths
etc etc were air born moisture can be produced, and all this moisture which is captured in the air as humidity should be
directed outside, if not, then there is a real possibility that this high level of humidity can condense on cold surfaces such as
windows, behind cold toilet tanks, on cold water pipes or cold surfaces such as exterior facing walls and possibly produce
condensation or water and in the long term it may produce mold and damage building components. Here is another
detailed publication from CMHC about Moisture and Air - CMHC Moisture and Air - Householder's Guide.
Controlling the Humidity Generated in the House is key, too high and you may produce moisture related problems like mold,
musty smells and or water damage, too low and you may feel dry throat, breathing problems, static shocks etc. In New
Construction - Homes are even more susceptible to moisture, due to the amount of water used in construction materials
which will evaporate over the first few years - can damage wood floors, cabinets and produce very high levels of moisture in
basements behind insulation and on cold water pipes. HRV's Heat Recovery Ventilators are also being installed in many of
the newer homes to help reduce the humidity/moisture levels. In some cases Dehumidifiers may be required in basements.
Where do you Ventilate:
1. Washrooms - Fans in washrooms should always be left on for approx 25-30 minutes especially after showers or the
very least a window should be left open to help draw that moist air outside. You may want to provide a timer for the fan. I
find timers to be more useful since it's easy to push a button and walk away. Some people feel connecting the fan switch to
the light switch is an option. Personally I don't like this since most people will turn off the light switch when they finish in the
washroom, however you may still need more time to reduce the humidity level in the washroom. For more info click the
following links; HVI Washroom Fan Guide, CMHC Washroom Fan Guide and Choosing an Energy Efficient Fan.
2. Kitchens - Range Hoods should also be used during and after cooking. Some earlier construction used flow through
range hoods which only captures the grease and not the humidity. Ideally range hoods should vent DIRECTLY outside. For
more info click the following links; HVI Kitchen Range Hood Guide, CMHC Range Hood Guide and Choosing an Energy
3. Laundry Rooms/Dryers - If you have a laundry room with a ceiling fan, you should be running this fan during the drying
cycles. Also make sure your dryer vent hose is connected directly to the outside and the hose itself is not damaged, leaking
moist air into the house. I would also make sure the dryer vent hose is of the flexible metal type, see image to the right. And
make sure you have the hose cleaned regularly of lint, lint can be combustible (catches on fire).
4. Cold Cellars (Cantina) - Basement cold cellars will typically have a window or a vent hole - this is used to allow fresh air
into the cold cellar to help reduce the humidity level, which can condense to free flowing water/moisture when the
temperature starts to drop. Don't block these holes or you may get musty smells and or water damage, such as mold.
5. Basements - May require a Dehumidifier which can help reduce the moisture levels. You may also want to insulate any
exposed cold water pipes, warm moist air can condense on the pipes and drip water, see picture to the right.
6. Attic - Most attic's will have roof venting and or soffit venting, some will have turbines and some will have fan's inside the
attic which will have either a manual switch or controlled by humidity levels. Attic ventilation or venting is required to reduce
the possibility of humidity condensing on the attic walls causing water related damages such as attic mold. Ventilating the
attic can also have other benefits read further...HVI Attic Ventilation.
FYI - have you noticed a switch directly above the furnace thermostat, usually located on the main floor family room, and
when you turn it on nothing happens, well the next time you turn it on see if the upstairs bathroom fan turns on. This is
called a Ventilation Fan Switch and what it does is it controls the upstairs bathroom fan so when the hot moist air rises the
fan can help suck it outside. It should be a three-way switch which means the fan can be controlled by the upstairs switch
and or at the switch above the furnace thermostat. Fell free to use it on those cold days when you don't want to open the
window but make sure the bathroom door is open.
Humidifiers (ONLY USED DURING THE WINTER) - Humidifiers are used to add moisture to the air. In the old days homes
were not as well insulated as they are today (approx 20-30 years ago), therefore air would easily flow through the house
and take out the humidity, remember humidity is not always a bad thing in the house, when controlled properly. That is why
you may see humidifiers attached directly to the furnace plenum.
The lack of humidity may produce dry throats, static electricity and poor living and health conditions. However, the
humidifiers that are attached to the furnace may not be used properly, meaning, set to a high number and forgotten...this
can lead to a large amount of moisture in the house or mold build up inside the humidifier (depending on the type of unit
you have). I recommend to use a lower setting and monitor over several days to see if too much moisture is added. One
way to tell is if there is moisture or water condensing on the windows, (make sure the condensation in the window isn't
because somebody just took a shower and the didn't use the fan) then lower the setting!. Today most people who need
humidification, such as for babies, will purchase a portable humidifier...just a thought!
If your home is older, with old windows and low insulation in the attic then you may be losing conditioned air/humidity and a
humidifier may make sense. If your planning on upgrading the windows, adding attic insulation and or updating insulation
strips around exterior doors...making your home more tightly sealed, then you may not need a humidifier.
Before you run out and have a humidifier installed on the furnace plenum - Consider living in the house for a winter season,
making sure you use your fans properly, read the "where to ventilate" info as stated above, and then see if your humidity
level is low causing dry air, dry throats etc. Still not sure then have a professional further evaluate your home and living
Why We use HRV's
A long time ago, homes were not as tightly insulated. Due to outside winds many air exchanges through the house would occur
which would allow fresh air to be circulated inside the house and at the same time remove humid moist air. As energy prices
insulation...although this began to cut down on energy bills another issue began to emerg...to much moisture was developing
inside the house, this moisture would condense on colder surfaces and begin to cause mold/rot damages.
A Heat Recovery Ventilator was developed which would take the warm moist air from inside of the house, channel it through an
HRV unit which would pass the air next to another channel of fresh air from the outside, thus heating the outside air up before it
comes back into the house. Heating the air this way saves on energy costs because you don't use your furnace to heat the
Canada Mortgage and Housing Corporation CMHC has much more information on their website Heat Recovery Ventilator which
will provide the benefits, description, how much you may save and design in much more detail. You can also look over the
Natural Resources Canada NRC guide on Heat Recovery Ventilators.
It's also important that you keep these HRV units clean. There are filters inside which get dirty and require changing, as well as
the unit itself may require cleaning due to the dirt and dust carried by the moisture collecting inside. CMHC has a video on
Maintaining your Heat Recovery Ventilator which I encourage you to watch.
Using an HRV
Many times people would ask me when do I use this HRV. It depends on your house and how air tight it is. There is a control
which is usually located near the thermosts for the furnace, sometimes the control is located near the HRV unit. There are a few
settings which can be used - Intermittent, Low and High. If you read chapter 4 page 17 of the NRC Guide it will help you decide
which setting is best for your specific needs.
Did you know that based on an April 2014 Toronto Public Health Report (Path to Healthier Air: Toronto Air Pollution
Burden of Illness Update) report that more than half of Toronto's air pollution is emitted within the city's boundaries itself.
Toronto Public Health estimates that air pollution in Toronto currently contributes to 1,300 premature deaths and 3,550
hospitalizations annually. This represents a decrease of 23% in premature deaths and 41% in hospitalizations as
compared with 2004.
A not-for-profit environmental watch dog, Toronto Environmental Alliance or TEA and Environment Hamilton have teamed
up to launch the INHALE - Initiative for Healthy Air & Local Economies Project. They have devised a unique approach to
monitoring the air quality. By using compact and easy to operate air quality monitors and GPS devices which can be
strapped to backpacks, bicycles, strollers and wheelchairs the devices can automatically draw in air and count the
volume of fine particulates which in turn can provide a guide to the air quality for that specific area of the city and TEA
has also gone one step further by actually mapping those findings on a city wide map (Fresh Air Finder Map) (as of today
South Etobicoke, Toronto and Hamilton have been mapped)...I highly recommend you read the full article in the North
York Mirror Thursday June 23, 2016 edition by Cynthia Reason and check out the Fresh Air Finder Map..
Webtrak is an online tool which provides real-time and historical flight path data so you can investigate aircraft operations.
Webtrak makes it easier for you to see what plane is overhead and to submit a noise complaint.
You could also plug in your home or office address and see if airplanes are in your flight path. This is a very cool site - I
plugged in my home address and it showed me a plane flying near my house in real time. You can even type in a specific
day and time to see what planes were flying overhead at that time.
I ran my mouse over the plane and it showed me the height or altitude of the plane as well as the origin of the flight, the
type of plane and destination...click on Webtrak to go to the site. Be sure to read the left side tab at the top "Start Here"
and the tab "Flights and Complaints" will allow you to enter your address. Be sure to investigate all the tabs and sections
there's a lot you can do with this site.
Aircraft noise has been a long standing issue in Toronto as well as most major and inter-city airports. As the population
increases in any given city the air traffic tends to increase. Most people know that aircraft can produce very loud noises,
but living in the flight path to a major airport may produce loud noises over a period of time which can have a more
profound effect on a persons mental state.
Typically noise is measured in Decibels (db) but how do you measure aircraft noise, over a period of time, type of aircraft,
night or day operation, weight etc. etc....many variables have gone into finding a formula to come up with the effective
perceived noise level.
The NEF or Noise Exposure Forecast was introduced by Transport Canada to provide a guide with a contour map to
visually identify the NEF rating around Toronto International Airport. The contour map will give you the NEF rating - look
very closely at the black lines and you will see a NEF Rating - (25,30,35,40). Basically the higher the number the louder
the noise. So what do the NEF ratings or numbers represent (when will people complain)...You can find the
information in Transport Canada Aviation Land Use Publication - Part 4: Noise. When you go over Part 4 you will be
directed to Table 1 which will provide the NEF values and the corrosponding Community Response to those values - the
higher the NEF number the more likely a complaint will be filed.
For more publications and links visit Toronto Pearson website
Toronto International Airport - Webtrak
If your thinking about buying a home or you already own a home near a railway line or yard there are some important CP
I also wanted to provide additional information and links, see below, which you may or may not find on CP and CN's
brochure and or web page. The Canadian Rail Atlas is very useful in zeroing on your actual community or street level and
identifying if a rail line is near by.
Canadian Rail Atlas - a website with a detailed map that outlines almost 45,000 Kilometers of railway network in Canada
where you can view class 1, short-line, tourist, commuter and intercity passenger railways. Make sure you read the USER
MANUAL first its very helpful in understanding the full use of the map, or go directly to the MAP.
Rail and Reason - A community blog for people affected by railway noise pollution.
Railway Noise Measurement and Reporting Methodology - was prepared to guide railway companies, citizens, and to the
Guidelines (see Guidelines below), the Methodology sets out procedures for the assessment of noise levels from existing
rail installations and installations under construction. The Methodology may be used by the Agency in reviewing noise
assessment submissions provided in support of cases for adjudication
Guidelines for the Resolution of Complaints over Railway Noise and Vibration - The Guidelines set out the collaborative
measures that parties must follow before the Agency will investigate a complaint. They also set out the elements the
Agency will consider in determining whether a railway company is in compliance with the noise provisions of the CTA and
the process to be followed in filing a complaint and the information to be submitted
Transport Canada - Website outlining railway safety - Acts, Regulations, Rules, Standards etc.
Heat Recovery Ventilator - Internal
Heat Recovery Ventilator - Control Panel
|Condensation on window = Mold/Mildew
Dryer Vent Hose - Flexible Metal
Bathroom Ceiling Fan
Water Pipe insulation - usually
cold water pipes
Humidifier attached to the furnace