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R-factors and "Our" factors©



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The stark reality of conventional insulation
 

We need to start with some basic physics by identifying the three types of heat movement which are:

Conduction and convection are methods in which heat flows.  Conduction utilizes a solid to conduct heat while convective heat flow reacts to fluid dynamics and the differential buoyancy which causes hot air to rise and vice versa.
Radiation is a source of energy in an electromagnetic wavelength, much like light.  Consider this: once radiation is stopped (absorbed), conduction and convection are created.

Webster's definitions:

Conductive Heat "To act as a conveyor, transmitter, or conductor, as of electricity, heat, etc.";
Conductive heat requires a solid entity to allow heated molecules to transfer heat. Conduction is fairly easy to limit by placing a non conductive or low mass separation in its path.

Convective Heat; "The transference of heat by the circulation of movement of the heated parts of a liquid or gas;"
Convective heat moves by the changing density of air or liquid. This creates a constant movement of heat as long as there is a temperature differential between the air or liquid and the source of heat. Convective heat movement is also fairly easy to restrict, just keep the medium (air or water) from moving. Fibrous insulation works well to limit convection.

 Now let's take a look at the not so obvious:

Radiant Heat; "In Physics, (a) the transmission of electromagnetic energy through space in straight lines; opposed to conduction and convection; (b) energy in process of transference through space; used especially of light and infrared heat."

When radiant heat is viewed as a form of energy, a wave length, rather than a type of heat movement, it becomes easier to understand how it behaves with fibrous insulation products. When radiant heat can be reduced from entering a home, conductive and convective heat (which increases power usage), also decreases proportionately. Therefore, if you can reduce the amount radiant energy, you reduce convective and conductive heat loads which increases comfort and significantly reduces the need for energy.
Reducing infrared heat can be accomplished by placing one or more highly reflective surfaces between the space being heated or cooled (your house), and the source (the sun or your ceiling during the winter).  Keep this in mind:  Heat always moves from a higher temperature to a lower temperature.

Radiant heat facts: