On Tue, 08 Nov 2011 12:43:59 +0000, Roger Chapman wrote:

Glass reflects so it will radiate comparatively little so windows should
appear colder.

Glass is complicated in that it's transmission/reflection abilties
varies with IR frequency. I *think* glass will transmit the higher
frequency IR radiation but reflect the lower. So sunlight with high
levels of HF IR gets through this is absorbed by objects behind the
glass which reraditates it at lower freqencies which the glass
reflects. This is how greenhouses work...

They should usually also feel colder to the touch as even double glazing
tends to be a worse insulator than all but thinnest of solid walls.

Yep, and in the context of IR radiation anything that does go through
isn't likely to come back.

--
Cheers
Dave.