Wood-Fire Boilers Cause For Concern

Conflicts between Wisconsin neighbors over emissions from outdoor wood-fired boilers are anticipated by the University of Wisconsin - Extension this winter season.

Wisconsin is among the states with the most number of residents using outdoor wood-fired boilers, which are popular in northern states because the fire hazard is external, wood storage and handling is done outdoors, and wood tends to be less expensive than other energy sources, the extension service says.

Along with that popularity come disadvantages, however, the service says, as the boilers are less energy efficient than other heating options.  And, when the boilers are not used properly, or are located in a dense area, conflicts with neighbors can occur due to wood smoke and resulting health effects, says David S. Liebl of UW-Extension’s Solid and Hazardous Waste Education Center.

The Wisconsin Department of Health Services reports that homeowners who are chronically exposed to smoke often complain of adverse health effects such as respiratory irritation, sinus issues or headaches. People with preexisting sensitivity or lung or heart conditions are more at risk.

Excessive boiler smoke can arise from the stove's design, or through inappropriate fueling practices, says Scott Sanford, rural energy program specialist with UW-Extension.

For example, operators should only add wood when there is a demand for heat, and only add enough for heating the next 8 to 12 hours (or less) to help reduce smoke emissions. Poor location, or weather conditions that prevent smoke from dispersing, can also lead to excessive wood smoke.

“Installing a stove with a stack that is too short, or at a distance too close to a neighboring building is probably the foremost reason for exposure to outdoor wood-fired boiler smoke,” says Sanford.

When smoke envelops a neighboring house or property, air quality degrades to conditions similar to a level that would cause the Wisconsin Department of Natural Resources to issue an air quality advisory for fine particles. The difference is that a DNR air advisory covers large areas of the state, not neighborhoods or towns, says Liebl.