Customer says tint works better on the outside ??

Bham · May 25, 2022

Okay all you smart people, help. I wish we had Smarty2shoes back.

Let me start by saying I don't have all the information on how this person is measuring heat, but here's the situation.

Customer calls and says that he's wanting some limo tint for the outside of his RV. I tell him that it won't last that way and he says he knows that, he is trying to replace what he has already put on. I ask him why he doesn't just put in on the inside and he says that it works better on the outside. He says he had it on the inside, took it off and put it on the outside. He says that it is 12° to 15° cooler when done this way rather than putting on the inside. :hmmm Now I'm not the smartest person about tint and maybe this is a thermal dynamic situation that I don't understand, but this seems wrong to me. Even if he's using a surface temperature type devise(laser) it shouldn't be this way, especially with normal automotive film.

Any ideas on how or why this person is thinking that the film is working better on the outside? :dunno

TintDude · May 25, 2022

Paging @Tintguy1980 :phone

I don't think it's going to work better myself. It's still going to heat and reradiate both ways. Maybe the wind has a slight effect since the outside surface may be a tad hotter than the inside, so maybe it would. :dunno

Bham · May 25, 2022

I don't know how he's measuring or what area, say internal temps or glass surface temps, but I really think he's missing a variable somewhere that is making him think it works better on the outside. I think we all know it shouldn't be the case, but something in this situation is missing. Maybe if I get to talk to him again I can find out more but I wanted to see what everyone else smarter than me thought.

Dano · May 25, 2022

I doubt I'm any smarter but I'll guess his logic is that he's blocking the heat before it hits the glass. I like to see the condition of the film in a year just for laughs.

Ryker · May 26, 2022

I would just run away from this guy as he knows more than we do.....

Auto film on the outside vs inside of single pane glass is not going to change much. Maybe a couple percent tser but not enough to make and real difference. Reflective film might get a few more percent yet but still not enough to really notice except with some high end meter.

WearTheFoxHat · May 26, 2022

Works the best when he parks the RV in a warehouse at night with the lights off.

doctor4766 · May 26, 2022

Can't say I believe fitting the film externally would make much difference as far as heat rejection goes but I did do it on one of my vehicles many years ago. Here's why:

I had a '94 Toyota HiLux Surf/4Runner that I had tinted with a 20% film.

Back then Toyota installed light bronze glass in a lot of their vehicles instead of green, so a 20% grey film looked quite nice on most of the windows........ except, the cargo windows, which have a reflective coating from factory on the inside.

Now no film, no matter how black it is would make those windows look particularly dark, so I tinted them on the outside instead.

This had a much better appearance and blended with the rest of the car.

I had it on there for months without it ever peeling off.

I even drove across Australia, from Perth to Brisbane and down the east coast through heat and snow at times and it held up well, until..... after a month on the road the vehicle was looking a bit crusty, so I gave it a good going over with my pressure cleaner. The scratch resistant coating started to come off and looked like crap so I peeled it off and never bothered replacing it again.

So whilst this has not helped the discussion about heat rejection, it shows that it can be done.

And by the way, I spent some time in Dubai a few years ago and noticed that many cars had their back window film installed on the outside.

Tintguy1980 · May 28, 2022

Placebo effect. 😆

Ima thinking the limo film on the outside could do a tad better since it's absorbing the majority of the solar energy before traveling through glass. If limo was on the inside and he was using AC, the absorption would reradiate toward the cool air inside versus out though the glazing system. Has it been tested in my time analyzing film products? No.

If you look at the TSER of an interior mounted 20% reflective film, it's reported around 79%. For an exterior mounted equivalent, the TSER jumps to 84%. 5 percentage points in film performance translating into a 10-15 degree improvement inside is at best questionable.

We all know that air passing over the outside surface will carry away any heat build up in the outer pane, so, traveling down the road at 60 mph you'll have a difference compared with sitting still. Same would occur if filmed on the inside. Sitting in a campground with 7-15 mph breeze ... well ... meh!

That's how it strikes me but, I have to say there are far too many variables involved that are not known for any of us to be believing his claim of 10-15 degree difference between interior mount vs exterior. Here's a few: Dual-pane? Tinted dual-pane? LowE dual-pane? Air conditioning efficiency? Limo tint metallized? Limo Ceramic? Limo straight-dyed? Air movement on the exterior surface? Measuring air temp? Measuring temp where the sun strikes a surface inside?

:runforhills