Please see the attached file for the fully formatted problem(s).
Determine which of the following 3 material substrates would have the best R-value or lowest thermal conductivity. The purpose is to determine which of the 3 materials would make the best insulator to heat and cold?
The following is given:
Solid wood (pine)
Wood w/ hollow-core air space
Wood with hollow-core space filled with rock wool
Assuming that the outside air temperature was 100 degrees F determine which of the 3 substrates above provides the best/greatest insulation value or resistance to temperature transmission. Explain why and show calculations knowing that:
C = 1/R where C = thermal conductance; and
C = k/thickness (inches) where k = thermal conductivity (Btu-in/ft2-hr-oF)
The key to this problem is in knowing the differences in thermal conductivities of the 3 materials (wood, air, and rockwool)
You can see a list of several different types of thermal conductivities ...
Thermal conductivities of three materials are compared.