Wood stoves used to be pretty uncomplicated devices. Even though they weren’t airtight and they weren’t especially efficient, these cast-iron stoves warmed plenty of New England farmhouses in the dead of winter.
Our forebears never considered the source of makeup air to replace all the heated combustion gases that were going up the flue. They didn’t need to, because back then, houses were leaky. As the stove burned its load of oak or maple, makeup air had no trouble finding its way into the house.
In the era of airtight construction, however, a wood stove is a different animal altogether. For one thing, stoves are more efficient. For another, the current emphasis on air sealing has reduced the number of cracks and leaks that were traditional sources of makeup air.
Writing in a Q&A post at GreenBuildingAdvisor, David Meiland delves into the problem by describing two common methods of solving the problem.
“I’ve been wood stove shopping lately and noticed that ‘outside air’ for wood stoves is done in a couple of different ways,” Meiland writes. “The European stoves in general do not seem to have a direct connection for the outside air duct — it’s what the salespeople are calling ‘proximity’ air, meaning a 3-inch duct from outside terminates very close to the stove, but does not connect.
“The American stoves are much more likely to have a direct connection. To me, a direct connection makes perfect sense, whereas the ‘proximity’ air looks like an air leak.”
Anyone care to venture an opinion?
Adding a trap to control air intake
John Klingel is among those who wonders whether a trap could be installed in the incoming air duct…