LISTEN...

Radiation heat transfer moves at the speed of light, because it is a type of light! These light waves are categorized in the part of the light spectrum called Infrared.

You can feel radiative heat from:

• Any surface that has any heat at all
• The surface of the sun through the window to the floor
• The sun to the roof, the roof to the ceiling

Radiation heat gain and loss happens primarily through windows...

You can see radiation using a FLIR camera - Focused Laser Infrared - which shows a thermographic reading of the hot and cold things in a space. The picture below shows a kitchen: