Page 47 - Green Builder Magazine Sept-Oct 2021

according to “Reducing Exposure to Cooking Pollutants: Policies outside more difficult and can require drywall demolition or
and Practices to Improve Air Quality in Homes,” a report by the relocation of the range, notes Kahre. “Anything that can create
Environmental Law Institute. Health impacts associated with these air movement up and across the face of the pan will be better for
pollutants, especially particulate matter, include cardiovascular dis- removing contaminants even at lower speeds,” he says. “Under
ease, respiratory disease and cancer, according to the report. cabinet or island hoods often have difficulty creating this effect,
Unfortunately, a microwave fan doesn’t exhaust most particu- especially when large pots are placed on the back burner, blocking
lates, says Nelson. the air flow.”
When selecting a range hood, Kahre recommends looking for
HOME ON THE RANGE--—BEST PRACTICES FOR RETROFITTING
one that vents outside and doesn’t recirculate air; one that is large
The simplest solution to control contaminants is to remove them
enough to cover as much of the stove top as possible; and one that
from the home at the source with a range hood, says Kahre. Some
operates quietly enough that people will be more likely to use it.
modern microwaves do vent to the outdoors, but “none can do this
He says quality range hood prices range from $250 to more than
as well as a range hood.”
$1,200, depending on the size, materials and functionality. A con-
Range hoods that vent to the outdoors are considered more effec-
tractor would need to install the range hood for proper ducting.
tive than other kitchen exhaust system types, particularly ductless
Matos-Rogers hired an HVAC company that specializes in design-
or recirculating range hoods that use a filter before blowing the air
ing systems from a building science perspective for their ventilation
back into the room, according to ELI’s report.
project. Ventilating the microwave took less than one day and cost
In a new construction home, venting a microwave fan or a more-
about $1,500.
traditional range hood is simple, since premade exterior vents and
“This seems fairly typical, though less-complex retrofits could
standard ductwork make most vents easy to vent, says Kahre.
cost less,” Matos-Rogers says. “Our microwave isn’t located on
an exterior wall and couldn’t be vented through the roof, which
RETROFITTING EXTERNAL VENTING IS MORE CHALLENGING
required running a longer duct to an outside wall. The contrac-
“The toughest thing about retrofitting a range hood is the duct-
tors had to remove the microwave to cut a hole in the cabinet for
work,” says Nelson. “If you have a 10-foot-high ceiling, that might
the ducting, and then it went right back in place when they were
work. But if you have an 8-foot-high ceiling, you might have to cut
finished. We just had to order the manufacturer’s adapter to con-
through the attic.”
nect the ducting, as it had been discarded during the original
A range on an island or an interior wall makes running ductwork
installation.”
MANAGING NOISE POLLUTION
Regardless of the type of range hood or exhaust fan you have in
your kitchen, it is useless unless you use it. A recent study by the
Center for Real Life Kitchen Design at Virginia Tech found that only
8 percent of people use their range hood regularly. Twenty-three
percent use it almost never or only occasionally. For many people,
the fan is just too noisy.
Panasonic’s WhisperHood IAQ range hood, which is part of the
company’s Cosmos Healthy Home System indoor air quality line of
products, offers an extremely quiet kitchen ventilation system.
“Fan noise is measured in sones, with an older kitchen fan typi-
cally measuring 6 or 7 sones,” says Nelson. “The WhisperHood
range hood can be as quiet as 0.3 sones, depending on the speed.”
While it’s best to address pollution at the source in the kitchen,
Nelson says installing a fan in a nearby powder room or other room
can help pull pollutants from the air.
“Panasonic makes a bathroom fan with a trigger that automati-
cally turns the fan on and off when it senses moisture in the air,”
Nelson says. “They’re easy to install and quiet and help pull mois-
ture and pollutants. No range hood is as quiet as a bathroom fan, so
that’s why we recommend putting bathroom fans in nearby rooms.
You don’t want an automatic trigger on your range hood to start it
up at 2 a.m.”
For Matos-Rogers, spending the time and money to install an
Need to vent. The typical recirculating range hood does little more than pull exterior vent on the microwave was worthwhile. “Tracking trends
air from the cooktop through a filter and then back into the kitchen. The on the IAQ monitors gives us verifiable data,” he says, “while
more-efficient, safer models vent outside and do not recirculate air. our senses notice the lack of smoke buildup and lingering smells
CREDIT: ANDRII ATANOV/ISTOCK from cooking.” GB

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