Window tint reverse heat insulation?
 

So random question, and had no idea where to post this but…

I’ve seen some window tinting companies also make claims that their window tints also keep the car warmer in the winter because INFRARED RAYS Go both ways. So the heat it blocks out from the sun coming in isn’t the only thing the tints do. It also blocks the IR from going out of the car also. I’ve seen some people simply claim that window tints are insulation.

This kind of makes sense, but is it backed up at all? Have any tests been done? Will a car that has window tints stay warmer longer in the cold winter?

Sure infrared may go both ways, no wonder those thermal-imaging cameras resort to it, yet I'm not sure to which extent window tint would retain heat inside the vehicle. I have never even seen such claims by any window tint manufacturer.

https://www.skylinetint.com/why-you-...car-in-winter/

I’ve seen the claim used on many other sites too but that’s one example. I just haven’t seen any tests done to actually prove this

Would love to get two side by side identical cars. One tinted and one not tinted. Bring the internal cabin temp to the same and then turn them off and measure the rate at heat being lost

window tint
 

PhD Richard Feynman claimed that simple window pane would prevent UV radiation from passing.
Visible spectrum radiation would pass through, then change to long-wave infrared as soon as it touched a surface, and get trapped inside the 'greenhouse.'
Selective coatings on films could be tailored to particular wavelengths, as far as 'radiative forcing' goes.
They could do NOTHING as far as 'conductive heat-gain, or 'heat-loss' were concerned.
Sitting close to the glass, you might not 'feel' your body chilled or heated so much, but the R-Factor ( or it's inverse, heat-transfer coefficient ) of the cabin would be whatever it was.
At some point you need 'insulation.'

Possibly beside the point of this thread, but here is something I've always wondered about:
A tinted window will absorb certain wavelengths of light as heat, heating up the glass. This heat is then radiated to the environment on both sides of the glass, though more to the side which is cooler.
Am I right, or missing something?

yeah the tint absorbs the heat. in some cases, the glass can crack and shatter if its thin and weak glass attached to the tint

yeah i definitely can feel the cold coming in during winter nights if i put my hand near the window. thats why i was asking if the claims are simply false about IR going both ways

I have never seen a car glass shattering due to tint.