Log home heating efficiency compared to a conventionally built home.
Handcrafted log home walls have comparable R-values to what you get with standard construction. However we have noted that log homes are often easier to heat than what you would expect from the R-values. There is more to the story — thermal mass. Logs offer better thermal performance based upon its mass.
If you are considering building an energy efficient home, consider the benefits the R-values of wood have to offer.
The R-Value of Wood
A material’s thermal resistance or resistance to heat flow is measured by its R-value. In a solid log wall, the logs provide both structure and insulation. The R-value for wood ranges between 1.41 per inch (2.54 cm) for most softwoods and 0.71 for most hardwoods. Ignoring the benefits of the thermal mass, a 6-inch (15.24 cm) softwood log wall has a clear-wall (a wall without windows or doors) R-value of just over 8.
Compared to a conventional wood stud wall (3½ inches (8.89 cm) of insulation, sheathing, and wallboard, for a total of about R-14) the log wall is apparently a far inferior insulation system. Based only on this, log walls do not satisfy most building code energy standards. However, to what extent a log building interacts with its surroundings depends greatly on the climate. Because of the log’s heat storage capability, its large mass may result in better overall energy efficiency in some climates than in others.
Logs act like “thermal batteries” and can, under the right circumstances, store heat during the day and gradually release it at night. This generally increases the apparent R-value of a log by 0.1 per inch of thickness in mild, sunny climates that have a substantial temperature swing from day to night. Such climates generally exist in the Earth’s temperate zones between the 15th and 40th parallels.