While burning wood provides an excellent source of heat, there are numerous disadvantages to this activity, including the relative amount of pollution it generates, its intrinsic messiness, its cumbersome weight and overall dimensions, and finally, the danger it poses if left unattended. Other heating sources, such as natural gas, have fewer disadvantages.
Soot, smoke and ash are the natural byproducts of a wood fire. Smoke must be channeled effectively through a chimney or flue in order to prevent asphyxiation. Soot is composed of particles of incompletely burned carbon that often adhere to the sides of the chimney, creating black marks that require frequent cleaning. While ash can be used as a base material for composting piles, in urban areas it is harder to dispose of in an environmentally friendly way.
In addition to soot, wood also generates piles of wood chips, sawdust, and other debris. Frequently, wood is a nesting place for spiders, crickets and other insects that can lodge within cracks or holes. As the wood is transported from an outdoor environment to an indoor environment, smaller pieces of bark may flake off, or insects may spring from their hiding places. Just as wood piles require frequent cleaning, fireplaces also require a daily sweeping and scrubbing regimen.
Different types of wood have different densities; balsa wood has a density of seven pounds per cubic foot, while pine wood has a density of approximately 52 pounds per cubic foot. Wood used for burning frequently has a density of between 20 to 40 pounds per foot. Because of this density, wood must be cut into two- to three-foot logs in order to be transportable. The amount of wood required for a substantial fire for an evening often requires between 10 to 12 logs, necessitating several trips.
Burning wood in a safely engineered chimney still poses a danger if an errant spark from the burning wood escapes the confines of the fireplace and alights on carpeting, furniture or other flammable materials. While fireplaces are often equipped with glass doors or mesh screens designed to prevent errant sparks, on some occasions accidents do happen. Wood driven fires must be attended at all times to effectively guard against this danger.