A baffle plate is a metal plate that sits over the firebox. The baffle plate blocks off the chimney and forces hot gases to remain in the stove for a longer period. This increases the efficiency and heat output of the stove.
Baffle plates may be composed of stainless steel, cast iron, firebrick, ceramic fiber board or any combination of these materials. Exposure to extreme heat deteriorates baffle plates, requiring them to be removed and replaced periodically. The use of a respirator is recommended when removing ceramic fiber board baffle plates. Some stoves have baffle plates that cannot be replaced, rendering them unusable when the plates deteriorate.