Between 9 18 4 the difference between the r values is caused by the thickness of the doors 1 model is 1 3 8 and the other model is 2.
R value of solid wood garage door.
R values climb as thickness of the material increases.
Even though it seems worse than other materials because wood has a lot of mass it actually can store energy not just prevent the ingress or egress of energy which is only what r values measure.
A 2 1 4 inch solid core wooden door for example has an r value of 3 70.
Higher is better when looking at garage door r values but it s not the only factor to consider.
Today s garage doors with polyurethane insulation will have an r value of 12 18 garaga s residential garage doors provide up to r 18 but you also want to choose a door that has otherwise good construction.
As a final tip understand that a garage door that has an r 16 value will actually help keep your home protected from heat and humidity during the summer months.
Another thing that effecting the r value is the material of the insulation.
There are mainly 2 materials for insulating garage doors polystyrene and polyurethane.
You also add heat to the garage every time you open an interior access door from the main house to the garage.
R value for solid wood doors this is a reprint of a recent article on some studies done to show that the straight r value of solid wood is misleading.