Just how energy efficient are your log properties?
Eaglerock log homes are energy efficient. The thermal mass capacity of log walls are higher than those of brick or concrete walls of the same thickness. Logs have the ability to store heat, and then relinquish the heat when it becomes cooler inside. Consequently the overall energy efficiency of a log home is better than comparable structures.
 The Nations Model Energy Code in Canada now recognizes the energy conservation benefits of thermal mass, which has been a victory for the Log Homes Council (LHC). The LHC has been claiming for years that a log wall's thermal mass does make a log home as energy efficient as a well-insulated frame wall.
This claim was not officially acknowledged previously, due to the difficulty in quantifying thermal mass. Log home owners had the home heating bills to verify these claims, but the Department of Energy and Code officials required more than empirical evidence. In direct response, the LHC has gathered scientific statistics from independent research projects to substantiate its assertion. At the heart of the debate were the R-values, or the measure of heat transfer through materials. R-value measures a material's resistance to the transfer of heat from one side to another. Log walls have the ability to absorb and store heat in their cellular structure.
The following is an excerpt from the LHC( Log Home Council).
Thermal mass is a material's capacity to absorb, store and slowly release heat over time. Logs do this well. The LHC set out to prove two things. First, logs have thermal mass because of their cellular structure, bulk and thickness. Second, this thermal mass provides significant energy-saving benefits because it released heat back into the house when temperatures drop.
Early studies proved thermal mass properties significantly reduce heating and cooling loads in moderate climates. The National Institute of Standards conducted the most important of these studies for HUD in 1981-1982. However, energy experts continued to question the value of thermal mass during the winter months in northern climates. They doubted its benefit when heat is needed constantly and thermostat settings are opposite outdoor temperature.
Two recent studies, both conducted in cold climate states, answer this question to the log home industry's benefit. In 1990, an independent testing agency, Advanced Certified Thermography, conducted a study for the Energy Division of the Minnesota Department of Public Service. It focused on heat loss through air leakage, assumed to be a problem with log walls because of their many joints. The study found the industry has substantially reduced air infiltration rates in the past 15 years. It credited this reduction to improved joint construction and the use of expanded foam sealants and gaskets on all joins and corner intersections. Leakage in the 23 test homes occurred in the same places it does in frame houses: at the peak of the cathedral ceilings, around window and door frames and along the tops of walls. The study concludes that air leakage in well-built, modern log homes is not due to their log walls.
NAHB's research Center conducted the second study for the LHC in 1991. It showed the thermal mass of log walls does significantly reduce energy use for heating in cold climates. it based its conclusion on a comparison of the actual energy use of eight log homes to the actual energy use of eight well-insulated frame houses during one winter. The number of houses were evenly divided between upstate New York and Montana.
The study also compared the homes actual energy use to their predicted energy consumption. The results led to the conclusion that log homes were as energy efficient as the frame houses.
"What is significant here is the log walls' average R-values was 44% lower than the frame walls" average R-Value." says Carter. "Clearly we must conclude the thermal mass performance of log walls is an advantage to log home owners."
An American study has shown that logs have a thermal performance value of R-22 for a building with 10" diameter logs with no insulation added. The logs used in our homes have a 12"-14" mean diameter, and with the addition of insulation being placed between the logs in the lateral grooves and notches add an even greater placed between the logs in the lateral grooves and notches add an even greater energy efficiency.
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