Many problems affecting buildings today are often caused by inadequate
ventilation. Here are the most common ventilation problems and how to
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problem appearing on the left border. If you want to see them all, just
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Fogged Up Windows
In autumn, the windows of your home become foggy
Likely cause: In Northern countries, when the cold season begins,
indoor windows have a tendency to become foggy when the humidity level
inside the house is too high. Moist air, when in contact with a cold surface
such as a glass pane, deposits its excess water. This explains the fogginess,
water droplets and eventually the interior ice build up at the base of
Practical solution: There are two ways to solve this problem:
Lowering the indoor moisture level to 40% RH or less.
Increasing the heating level to keep glass panes at a higher temperature.
The most practical solution is to lower the humidity level to 40% or
less. This is usually done by installing a heat recovery ventilator. But
be careful: All heat recovery ventilators are not evenly effective during
autumn. When the outside air is very moist, a traditional passive heat
recovery ventilator that only exchanges air between the inside and the
outside will not help at all.
To get good results, whatever the season, the Nilan VPL-15
is probably your best choice. The VPL-15
is different from other HRVs because it contains an active heat pump that
has the power to extract water from the air. It works as a real dehumidifier,
extracting moisture by condensation.
Frost on windows
During winter, frost and ice appear at the base
of your windows. In the sun, the ice melts. Outcome: puddles on the windowsill
and water dripping down the wall.
Likely cause: The temperature at the base of your windows is too
low for the humidity level inside the house. Remember, in winter, the
interior humidity level should be below 40% RH.
Practical solution: Lower the indoor humidity level to 40% RH
or less with a heat recovery ventilator (VPL-15).
When the outside temperature is below -20C, maintaining an interior moisture
level as low as 20% could be necessary to totally eliminate the ice build
up on the windowsill. However, we must also take into consideration the
well-being of the occupants and not keep the air too dry. In winter, 40%
RH is usually regarded as comfort zone. This humidity level will not cause
many problems for your windows even if the outside temperature falls occasionally
It is also important to let warm air circulate around your windows. Dont
completely cover them with blinds or drapes. This prevents warm air circulation.
Damp Basement, especially in summer
During summer, your basement is really humid. Odors
and mildew infect the air.
Likely cause: In summer, two sources can cause a high humidity
level in the basement:
1. Outside air which contains a lot of moisture
2. Underground water. When the soil drains poorly, or when the foundation
damproofing is inadequate, the underground water can pass through the
foundation by capillary action.
Practical solution: Before attempting to dig around the house
in order to replace the foundation drains or to redo the damproofing,
which are very expensive undertakings, try first to dehumidify the basement
air. For that job, the VPL-15
is an excellent choice. In 24 hours, it can extract up to 3 gallons of
water from the ambient air. In addition, by continuously replacing stale
air, odors will disappear, making the basement much more comfortable.
Asthma and allergies
You suffer from allergies or asthma
cause: Many researchers suspect the diminishing air quality in buildings
has caused the enormous increase in asthma cases. According to Science
et Vie, March 1992, consultations at the emergency room of the Trousseau
Hospital in Paris, increased from 14 in 1973 to 1093 in 1989. This increase
coincides significantly with the beginning of energy saving measures in
Practical solution: The VPL-15
offers many advantages to relieve summer allergies caused by pollen. With
its functions of dehumidification, air conditioning (8,000 BTU) and ventilation,
the VPL-15 makes the home much more comfortable even when the windows
are closed. In addition, the optional micro-filtration system easily traps
microscopic particles making the inside air pollen-free.
For asthma cases, it is without a doubt that better ventilation of enclosed
spaces can make a big difference.
Please take also a look at the Air-T-Rex. It is a simple and affordable
solution to get rid of airborne particles like pollen and dust.
Indoor swimming pool
After the installation of an interior swimming pool,
the indoor moisture level suddenly increases to dangerous levels.
Likely cause: When the temperature of the water in the swimming
pool is higher than the temperature of the ambient air, the evaporation
increases causing an equivalent rise in the household moisture level.
We know that in winter, a humidity level higher than 40% is hazardous
for the house and its structure.
Practical solution: A multifunctional ventilation system offers
probably the most effective solution for this type of problem. The VPL-25
is the most often installed model. Its superior ventilation power allows
a high rate of dehumidification and its mini-heat pump guarantees considerable
Cigarette and bad odors
Cigarette smoke and other bad smells annoy you.
Likely cause: Lack of ventilation. The current norm recommends
a complete air exchange each 3 hours. That means that if you want to breathe
a good quality air, it is necessary to completely renew the indoor air
at least 8 times a day.
Practical solution: Whatever your needs, Nilan has a system that
will meet them. With air flows from 60 cfm (cubic feet/minute) to 10,500
cfm we have solutions for a room, a whole house or an entire commercial
building. Our specialists can calculate exactly how much ventilation you
need for whatever application you have.
Pollution at work
Your building indoor air quality does not meet the
requirements of regulating authorities.
Likely cause: Lack of ventilation or too much particles in the
Practical solution: This problem requires an investigation on
the site. This is not an easy problem because it generally involves the
entire building. On the other hand, if you need a fast, simple and low
cost solution to protect yourself, please take a look at the