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Haha! Searching for ceramic window tint to cut down on the greenhouse effect I ran across this! Look at the customer pics....
Two things from personal experience:
1. The cerramic window film will not lower the interior temperature of an Insight. I fell for this notion and had film installed. I did tests of two identical Insights, one with film - one without, parked parallel to each other. The interior temperature of the two was nearly identical. Apparently, sun heats the film which heats the glass, which heats the car. After a couple of hours in the sun, you can lay your hand on the film covered glass and definitely feel it is hotter than the clear glass. I recommend reflective window shades, or a silvered car cover.

2. Most states set limits on how dark the film can be. Be sure you understand your state law. If it is too dark, it is an open invitation to be stopped by the police.

A final observation, from the number of crappy film jobs one sees on the streets it seems clear that it is hard to install correctly. If you want it to look good, hire a professional or do a lot of reading on how to do it right.

Looks great on a Citrus, but totally ineffective in controlling interior heat:(
 

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Two things from personal experience:
I did tests of two identical Insights, one with film - one without, parked parallel to each other. The interior temperature of the two was nearly identical. Apparently, sun heats the film which heats the glass, which heats the car. After a couple of hours in the sun, you can lay your hand on the film covered glass and definitely feel it is hotter than the clear glass. I recommend reflective window shades, or a silvered car cover.
I remember debating someone about this. Instead of heating stuff in the car which heats the car you heat the tint which heats the air in the car and the glass through MECHANICAL contact (atoms shaking atoms, to put it visually.)

I wonder how much cooler a car with a white or silvery mylar "emergency blanket" draped over everything in the back (leaving the rear view unobstructed, for example, to reduce heat load while driving somewhere with a lot of sunshine) would be over a car without said sheet.
 

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If only one could chrome wrap windows without annoying the heck out of everyone on the road lol.

Although of all the cars I've been in, the Insight stays the coolest for some reason. Maybe some factory coating on the windows that helps? Even the Prius, which has some sort of factory coating, isn't any cooler than my Civic was, but the Insight stays relatively cool inside compared to other cars. No tint or anything.
 

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Discussion Starter #5
Two things from personal experience:
1. The cerramic window film will not lower the interior temperature of an Insight. I fell for this notion and had film installed. I did tests of two identical Insights, one with film - one without, parked parallel to each other. The interior temperature of the two was nearly identical. Apparently, sun heats the film which heats the glass, which heats the car. After a couple of hours in the sun, you can lay your hand on the film covered glass and definitely feel it is hotter than the clear glass. I recommend reflective window shades, or a silvered car cover.

(
INteresting. Here's somebody else that makes the same claim. And he used the expensive stuff....

https://forums.tesla.com/forum/forums/experiment-3m-crystalline-tint-makes-zero-difference-cabin-temp
 

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Discussion Starter #6
I wonder what this perforated film would do? I would probably just do the hatch glass. I don't have a rearview mirror and only use the wing mirrors, which is legal where I live. I'm tall and the rearview mirror obstruted my view out the front, plus I've driven trucks and trailers most of my life so I'm comfortable with wing mirrors anyway.

https://vvividshop.com/products/one-way-perforated-white-window-vinyl-privacy-window-film

This stuff comes in white and black. Obviously white would be better for heat....

 

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INteresting. Here's somebody else that makes the same claim. And he used the expensive stuff....
I used the expensive stuff also - a nationally known brand professionally installed.

I feel kinda foolish having fallen for this ruse. I have always believed that a product doesn't really have to perform, it is enough just to convince a large market that it does. Yet, I fell for it. DON'T WASTE YOUR MONEY ON FILM!
 

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So what happened to "Whose car is this"?
 

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retitle

Yeah, went off the rails, but it evolved into something worthwhile, so I'm going to retitle it;)
 

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Without looking it up, because what fun would that be, it at least changes the radiation from skin/interior damaging to just heat right?
 

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INteresting. Here's somebody else that makes the same claim. And he used the expensive stuff....

https://forums.tesla.com/forum/forums/experiment-3m-crystalline-tint-makes-zero-difference-cabin-temp
Mechanical engineer here with a background in thermal dynamics and optics. Let me share some knowledge.

1) I have not measured the IR / UV transmittance of the insight's factory windows
2) The reason why the Tesla saw zero improvement with the in cabin temps during their testing with CR90 was that the Tesla comes from the factory with glass that already blocks significant IR (IR spectrum carries the majority of the heat energy). This was confirmed directly from a Tesla Engineer. (I live a few mi from the Fremont plant and work closely with many Tesla guys). The CR90 didn't add anything in this case, causing his test results to appear like the tint has zero effect. Doesn't <120*f sound a bit cool for a car interior to you? (I've measured 180*f in my other cars)
3) Dark doesn't mean better heat blocking abilities. I made a chart that you can use for reference. I apologise for it being a phone pic and not a screenshot. CR90 for the front windows and windshield, CR70 for the rear and quarters is legally and visibly optimal. It's just very expensive. There is a diminishing returns effect with darker tint, so why lose your ability to back up at night, etc.
4) As the first post mentioned, tint helps with the greenhouse effect. The goal of tint is to keep the sun from hearing up the inside of the car. Less IR into the car = lower temperature on the inside of the car. Doesn't matter if the glass is absorbing that heat while driving, because you are driving and cooling the glass via convection air cooling. The effect? Less AC usage = MOAR. LEAN. BURN. (Twitches)
5) Eventually all things reach equilibrium temperature while parked. Window tint helps negate the effects of greenhouse heating effect, but don't fall for some of these false tests online. Crack the windows and use a reflective windshield visor, and park in the shade you are more worried about temp when parked.

6) Again, I haven't tested the light spectrum transmittance of the insight's glass. I'll see if I can test it at work, but it is difficult to do without taking each window out. Someone needs to do this and then we can confirm the effects of IR blocking tint.

Moar lean burn gentlemen. Moar.
 

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Without looking it up, because what fun would that be, it at least changes the radiation from skin/interior damaging to just heat right?
All the tint brands I researched blocked >99% of UV spectrum, regardless of % visible light transmitted. Yes, it's fantastic for your skin. That said, I didn't bother researching the specs of cheap tint since I was looking for specialty tint that blocks the most IR to visible light ratio.
 

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All the tint brands I researched blocked >99% of UV spectrum, regardless of % visible light transmitted. Yes, it's fantastic for your skin.
This I can believe, but that isn't where the heat comes from.
I was looking for specialty tint that blocks the most IR to visible light ratio.
And what were results of your search on IR and visible spectrum. From my experience, it is hard to believe that any of the "cerramic" films are very effective in that range:(
 

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3) Dark doesn't mean better heat blocking abilities. I made a chart that you can use for reference. I apologise for it being a phone pic and not a screenshot. CR90 for the front windows and windshield, CR70 for the rear and quarters is legally and visibly optimal. It's just very expensive. There is a diminishing returns effect with darker tint, so why lose your ability to back up at night, etc.
The pictures have too little resolution to be readable for the most part, but...

On the left hand thumbnail, can you tell us what the left hand(vertical) axis is? Is it % blockage of IR for example, or some other parameter?
 

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The pictures have too little resolution to be readable for the most part, but...

On the left hand thumbnail, can you tell us what the left hand(vertical) axis is? Is it % blockage of IR for example, or some other parameter?
The vertical axis is % IR blocked / % Visible light spectrum blocked. The goal of the graph is to maximize heat rejection at the least possible cost of drivability. 3M's crystalline line CR90 and CR70 massively won, and I stopped inputting data at that point since that tint line was a match for what I needed. There was several other lines of tint by 3M that could be similar.

And thanks for the welcome 😁 I will contribute where I can.
 

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The vertical axis is % IR blocked / % Visible light spectrum blocked. The goal of the graph is to maximize heat rejection at the least possible cost of drivability. 3M's crystalline line CR90 and CR70 massively won, and I stopped inputting data at that point since that tint line was a match for what I needed. There was several other lines of tint by 3M that could be similar.

And thanks for the welcome 😁 I will contribute where I can.
Hey @coreyosaur, apologies in advance for any ignorance. How is the IR blockage measured? And what is happening to the infrared energy - is it being reflected back out into the sky (ie, if IR were visible, would the glass appear mirrored), or being absorbed by the film and transferred to the glass via vibration at the atomic level, or converted to energy at another frequency (though I have no idea where that would be), or?
 

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The vertical axis is % IR blocked / % Visible light spectrum blocked. The goal of the graph is to maximize heat rejection at the least possible cost of drivability.
OK, got it. The problem here is in definitions. The term "blocked" is distinctly not "reflected" or directed away. If blocked means adsorbed, then the IR is converted to heat in the film, as I believe from my measurements to be the case. Just basic thermodynamics that the IR energy has to go somewhere - if not reflected, then adsorbed. The IR will heat the film, which heats the glass, which heats the air in the car. If not the case, then why would filmed window glass be much hotter than un-filmed glass?

I don't mean any disrespect to your engineering degree, but I have one also. I find that referring to my degree doesn't inherently shed any light on a question about the physical world. It may help -it may not. Engineers may have fewer blind spots, but they still aren't immune from making errors.

Can you explain the physical observeables in play: 1. the filmed glass is much hotter than the unfilmed glass, and 2. the two identical cars, one filmed- one not, reach the same interior temperature after 2 hours.

I tried to find unbiased, peer review information on this subject, but I could not. All the info I found on the internet is from various film purveyers and therefore highly suspect.

I could go on, but I've made my major points.
 
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