You would need only 2,340 btu/hr for a 10’ x
15’ room with an 8’ ceiling. Most room
vented fireplaces put out over 30,000 btu/hr. You
would need a room 96 feet long to be able to accommodate
that output in a room vented product!
6. What else should I know about
the differences between direct vent and unvented
hearth products?
For starters, you should check with your local building
code to confirm if unvented products are allowed
to be installed. For instance, there are several
states that ban their use entirely.
Second, consider the ”comfort control” you
have with direct vent models. Many offer options
that allow you to put excess heat into other rooms,
or outside the home completely if you choose. (A
nice feature when you’re entertaining a room
full of guests.) Since all the heat form an unvented
type product comes into the room, it can make a room
uncomfortably hot in a hurry!
Last, while unvented products are technically “safe” when
sized, installed and operated properly, there are
several reputable sources and industry experts who
do not believe they are “healthy” in
certain conditions.
“We truly believe that direct vent fireplaces
and inserts represent the “Healthy Hearth’ choice
of you, your family, your friends; for anyone who
gathers at your hearth. Enjoy…Relax…Breathe
Easy!”
But don’t just take our word for it,
consider these statements from industry experts
when making your decision:
“An unvented gas fireplace that’s safely
sized needn’t pose any acute health hazard.
But our tests confirm that these heaters contribute
significantly to indoor air pollution. If you are
planning to buy a gas fireplace, a vented model should
be your first choice.”
Consumer’s Report Magazine - November,
1998
“The data in a AGAR (American Gas Association
Research) report on unvented appliances suggests
that tighter houses may not be suitable for the installation
on unvented products. This is especially true for
colder regions of the country, or when cold snap
periods are occurring in milder zones.”
Paul Stegmeir
Hearth industry expert
on indoor air quality
“Direct vent, sealed combustion models
are the only type of gas fireplace we allow in
our Health House project”
Diane Walsh-Astry
Director, National Health House
American Lung Association
