Ventilation & IAQ - FAQs
Are the contents of indoor air really that bad?
Maine residents face exposures:
Radon Formaldehyde Carbon monoxide
Lead Asbestos Mercury
Pesticides Chemicals Tobacco products
That's not including biological contaminants such as:
Viruses Bacteria Molds
Dust mites Allergens
On top of that, all of these are trapped in the air we “re-breath”.
In our attempts to be energy efficient, we live in tightly sealed homes
for up to 8 months a year. The tighter the construction, the greater
the concentration of these pollutants – and our bedrooms are the
These pollutants can have an affect on your quality of life and daily tasks and routines. Read Ventilation Rates and Office Work Performance for more information.
But I'm healthy, am I really at risk?
Certainly kids and seniors are most at-risk, however, indoor air
pollution can effect you in a variety of ways. Eye irritation, morning
grogginess, fatigue, dizziness, diminished ability to concentrate,
headaches, runny noses, irritated throat and lungs are issues
regardless of your age.
Breathing dirty, mold/bacterial laden air for long periods of time can
affect any part of your body, including, lungs, heart, liver, kidneys,
brain and nervous system. According to the EPA, indoor air can be up
to five times more contaminated than outside air and sometimes
What is Sick Building Syndrome?
From the EPA "The term "sick building syndrome" (SBS) is used to describe situations in which building occupants experience acute health and comfort effects that appear to be linked to time spent in a building, but no specific illness or cause can be identified. The complaints may be localized in a particular room or zone, or may be widespread throughout the building. In contrast, the term "building related illness" (BRI) is used when symptoms of diagnosable illness are identified and can be attributed directly to airborne building contaminants."
[Signs] of SBS may include:
Building occupants complain of symptoms associated with acute discomfort, e.g., headache; eye, nose, or throat irritation; dry cough; dry or itchy skin; dizziness and nausea; difficulty in concentrating; fatigue; and sensitivity to odors.
The cause of the symptoms is not known.
Most of the complainants report relief soon after leaving the building.
What can cause SBS?
There are a number of potential causes which the EPA has kindly collected and presented here: https://www.epa.gov/sites/production/files/2014-08/documents/sick_building_factsheet.pdf
There seems to be a lot of moisture in my home,
is that bad?
Mold spores are just waiting for enough moisture to start growing.
Mold uses the cellulose in wood fiber as a food source – this is how
dead trees disappear in the woods. The outbreak of Legionnaires
Disease demonstrated just how deadly mold can be. There are a
number of ways that excess moisture occurs in a home, and reducing
them is a good step forward to helping reduce this issue. Some of
these examples are:
Plumbing and roof leaks
Cooking without a range hood
Showering without properly venting the steam (bath fan or
Larger families or homes with multiple large animals
Improperly vented clothes dryers
Drying clothes on an indoor drying rack or line drying indoors
Flooding and sewer backups
Poorly maintained gutters, downspouts and drains
Water seeping into the basement without proper drainage
Open and/or unvented crawl spaces
With so many problems, I'll just get an air
purifier! That will fix my air, right?
There are 3 main types of air pollution: particles, gases and moisture.
Most room air filters only filter out particles. The gases may be the
biggest threat to our health. A filter will do nothing for moisture and
depending on the type of unit, likely will not help with gases. They
also do just a relatively small area: one room. So to help with the
whole house, you would have to get one for each room. Air purifiers
do not effectively aid in the reduction of radon in the air.
So is Radon really that much of an issue?
Radon is an odorless, naturally occurring gas produced from the
decay of uranium in the ground. It has a high statistical correlation
to lung cancer for people who have never smoked. Here in Maine,
the problem is serious. In residences tested, from 44% to 74% of the
homes (depending on the county) produced levels high enough to
require remediation. According to recent CDC reports, Maine has a
Lung Cancer death rate 20% higher then the national average.
Radon is the number one cause of lung cancer among non-smokers,
according to EPA estimates. Overall, radon is the second leading
cause of lung cancer. Radon is responsible for about 21,000 lung
cancer deaths [in the U.S.] every year. About 2,900 of these deaths
occur among people who have never smoked.
What if I don’t want the system running all the time?
Since our focus is to improve the overall health of occupants like heating your home, our recommendation is to run the system while the home is expected to be lived in. Main controllers always include the option to turn the unit off, whereas others have a manual on/off button on the unit itself.
Won’t we lose heat if we are constantly bringing
in fresh cold air?
Yes. You will lose some heat. This is why we are tightening up our
homes. The truth is, you already are losing heat energy by running
the bath fan, clothes dryer, range hood, or any other movement of
warm air from inside to the outside. The difference is that with a
mechanical ventilation system, you can control the air flow. Energy
recovery ventilation systems provide a way of ventilating a home
while minimizing energy loss. They reduce the costs of heating
ventilated air in the winter by transferring heat from the warm
inside exhaust air to the fresh (but cold) outside supply air. In the
summer, the inside air cools the warmer supply air to reduce
A better question is whether we can stay healthy and avoid health
care costs by ventilating out harmful pollutants!! Because of the health care burden of our houses, the Government is making steps to address this issue.
If my system is on all the time, how much of an
increase in my electric bill can I expect?
There are a lot of variables to consider however, the average home is
between $6 and $10 per month.
The Broan ERV200TE uses under 20 watts at low speed and that
equates to $2 a month in electricity usage.
The Venmar EKO uses as little as 26 watts and uses less then $3 a
month in electricity.
Others use a little more, some up to $20 per month.
The question is really this: Is your health worth it?
What if it's the stuff in the outside air that bothers me most?
Allergens from outdoors like pollen, especially in the spring time, can cause a lot of problems. One of the advantages of a ventilation system is you control the inbound air stream; this gives you the opportunity to filter (clean) said air stream. A variety of filters can be used such as Pleated, Carbon(Charcoal), Electrostatic and HEPA Filters.
Pleated Filter - UL Class 2 filter. Arrestance (measure of the ability of an air filtration device to remove synthetic dust from the air. The arrestance describes how well an air filter removes larger particles - such as dirt, lint, hair, and dust). is 90-92% and efficiency at 1 micron is 21%
Carbon Filter(Charcoal) - UL class 2 filter. Average arrestance is 80% according to ASHRAE.
Electrostatic Filter - The filter's electric field captures particles of 0.3 microns or more without producing ozone or ions. The efficiency at 1 micron is 90%. DC 12 volts & uses 1 watt.
High Efficiency Particulate Air (HEPA) Filter - Removes 99.97% of particles that are 0.3 microns (also called micrometer) or larger.
As a point of reference, the average human hair is ~50 microns in diameter; the longest chromosome in our DNA is ~10 microns long and a strand spider web is ~3 microns in width.
Is it a big job to install an air exchange system
in an existing home?
It all depends on the home. Most can be installed in 3 to 5 days
How long before I notice an effect on my Indoor
Many customers notice that within only a few hours, the house feels
fresher. Many of them have shared with us the various benefits they
Is a whole house system going to be noisy, will I
Due to these systems being designed for homes, there are ratings on the noise level that these systems generate and are called sones. These units are designed to produce little noise. Most systems when run on low speed, are very quiet. High speed will carry a higher level of noise due to increased fan movement and air speed and is typically is not a complaint issue in the home. In fact we have had very few complaints on noise levels.
Considering other things in the home that produce noise such as furnaces, heat pumps, refrigerators, air conditions most people think these systems produce a lot less noise than those. Unit location plays a hand in how much noise can be heard.
What exactly does home ventilation mean?
As we move to the future we try to be as energy efficient as we can. With that, we close up our homes nice and tight to make sure no heat gets out; but is living in a balloon really very healthy? Energy-efficient homes -- both new and existing -- require mechanical ventilation to improve and then maintain indoor air quality.
How do I know if it's right for me? Is it expensive?
The first thing you need to consider is how high a priority is the well being of you and your family? If there is something harming you and you can't see it, do you want to know? If you knew, would you want to fix it? Price varies per house by quite a bit. The best way to know the cost is to Request An Estimate. Generally speaking however, for a ventilation unit prices range from around $1,000 to about $3,000. The higher you go in price, the more energy-efficient the system is.
What process do you take to create an estimate for me?
There are several questions we ask to help us determine the closest possible response. Please see our estimate page, currently on our .net website to Request an Estimate.
My electrician/plumber/contractor says he can do it for a lot less, why is that?
If they're installing a system properly for a significantly lower cost there's probably something wrong. In the United States there is no certification and no requirements for a "correct" system. Kurt Johnson went to Canada where they have a certification program and received proper training for system design and installation through the HRAI SkillTech Academy, Certification #8630.
What about specific rooms; or just ventilating my basement?
Ventilating a basement is a good start as radon and mold are very common there. But due to a phenomenon known as 'stack effect' air wants to move up. Ventilation in the basement will reasonably reduce the effects of radon and mold, but it's still possible to find their way into the rest of your home. Regarding effectiveness of reducing radon levels, in a basement or elsewhere, the Maine Radon Director Robert Stillwell has stated that ventilation can reduce radon by up to half.
What is Cross-Flow, Counter-Flow an Enthalpy Wheel?
These are different design strategies each intended to extract the most heat and/or moisture from the outgoing airstream as possible.
Cross-Flow is the more commonly recognized in which the shape is a square turned at an angle, some call it a diamond, in which the air moves through in an X shape without mixing.
Enthalpy Wheel, also called a rotary heat exchanger or thermal wheel, is a cylinder turned on it's side inside of a cassette. Sensible efficiency around 85%. We usually encounter these in older units, and the cost to replace the wheel is roughly the same as a newer unit.