Glass Roof Question

[xyeahtony]

Quick follow up, you mentioned you had a Lexus previously. How would you compare the service levels?

A lexus dealer will pamper you more. The one i used to visit had shopping and a buffet inside haha. You won't find such things in a Tesla service center, but at least you'll get a Tesla (more often than not) loaner

Then again you shouldn't be visiting a Tesla Service center often if ever.

 

[houstonian]

Quick follow up, you mentioned you had a Lexus previously. How would you compare the service levels?

Leased a ES350 for a family member from Lexus two years ago. Toyota's done a good job of instilling motivation (fear?) in the Lexus dealers to focus on the customer IMHO. I did not see any turnover with the dealer employees I dealt with, and all were curious and strived to anticipate my needs and questions.

Just completed the 12.5k service on my 2017 S a few days ago (first time to Tesla service) and was pleased. Tesla service is considerable beneath Lexus, but not in the way you're thinking.

Tesla service struck me as being more straightforward regarding scope of work than Lexus and Tesla's operation appeared as being less complex. The service center itself is like the car - spartan, but not bare. I only noted three front-of-house employees at the Tesla SC (greeter/receptionist and two service advisors), but there may have been more. Checking the car in, going over the service, checking out the loaner, and getting on my way took about 25m - with about 5m of me asking questions - and this did not strike me as taking as long or requiring as many steps when dropping off the Lexus (or my Acura before) to their respective dealerships.

Lexus OTOH operates polished, amenity-laden, massive service center operations. You drive up into a large facility, 10+ service advisors are nestled nearby to check you in, their paperwork is impressive, verbose, and printed in triplicate. The waiting areas strike me as being similar to an airline lounge at an airport sans the booze. Their scope of operation feels far larger than Tesla SCs (again, more potential mechanical repairs on an ICE) and I can't recall a time with either Lexus or Acura where I was able to drop the car off at service and get out in a loaner in under 45m.

I prefer the quicker in-n-out of my Tesla SC experience to Lexus/Acura. I want to drop off, collect the loaner, return, and reclaim my car ASAP. I certainly appreciate the effort Lexus invests in making their service centers nice and am certainly grateful for them, but the pros of that do not cancel out the efficiency of my (only one so far) Tesla SC visit.

 

[gowthamn]

Why can't they implement magic sky control.

 

[TexLaw]

Quick follow up, you mentioned you had a Lexus previously. How would you compare the service levels?

Lexus service always was excellent. Fortunately, I've only dealt with Tesla service one time, and they also were excellent.

 

[Italia81]

Thx, I'm pretty much sold. I just have a to figure out my charging situation and lease vs. buy. It looks like the lease bakes in the tax credit? I keep my cars a really long time and have always bought but it seems like cars are just going to be come devices going forward. People might want to keep upgrading them for better batteries, tech, and charging time.

 

[Snowstorm]

I was wondering about UV IR protective property of the glass roof and rear hatch and it looks like that it should be pretty UV proof as it is made of laminated glass like the windshield. You can see this if you look the the junction of where the hatch meets the roof. The glass on the top is made of 3 layers, unlike the side windows.

This tells me UV resistant is high, not sure about heat or IR though.

 

[dknisely]

We took a road trip to central WA state last weekend, where it was over 100F all day, and there were no problems with uncomfortable heat in my pano-roof model (sunroof, but basically the same as pano all glass rood in exposure). I had ordered a screen/sun block insert, which I have yet to pull out.

I really don't think you'll have a problem, but even if you do, the screens will block almost all the light if needed.

 

[Buster1]

We discussed the heat issue the other day at our local Vegas Service Center. The salesman told us heat really wasn't a problem, and that actually the glass roof cars were cooler than a comparable solid roof car. This was due to the minimal insulation and heat conductive properties of a metal roof and underlying insulation, vs the glass roof's ability to reflect all that heat and not conduct it.

Now I'd like to think I've seen a few magic acts here in Vegas, and that I'm a smart-ish man...but the salesman's pitch was not very convincing. Maybe he's right!? But I kinda expected him to pull a long handkerchief from his sleeve next.

Maybe we can do a side by side test somehow, with two cars sitting in the sun. I'd like to see that.

 

[Snowstorm]

I call BS. The glass roof maybe very good enough, but it cannot beat an insulated metal roof when it comes to heat rejection, especially not a white metal roof.

Based on my limited knowledge, there is no way a dark coloured glass roof will reject more solar energy than a light coloured metal roof.

There are three things sun light/energy of all wavelength can do. Reflected away, transmitted through, or absorbed. Of the 3 methods, only reflection will mean it is not heating something on the car up. If it is absorbed, then the roof will heat up and how much of it you will feel depends on the insulation.

A glass roof will transmit more as you can see through it. It will reflect less than a light color metal roof as it is dark. Whatever that is absorbed by the roof/glass will heat the inside up more as there are no insulation.

You can have a pretty good glass roof that blocks almost all UV, most visible and IR if it is properly made and coated, but there is no way it will beat a metal roof with insulation, especially not a white metal roof, for the ability to reject heat overall.

 

[DarkMatter]

Except not all Teslas are white. I suspect a black or dark gray Tesla with a metal roof takes in more heat than a pano or all glass roof. After all even though you need to see through it, it can be reflective and thus opaque to the IR and UV. Unless you're a cyborg, you'll never notice.

 

[SageBrush]

I call BS. The glass roof maybe very good enough, but it cannot beat an insulated metal roof when it comes to heat rejection, especially not a white metal roof.

Based on my limited knowledge, there is no way a dark coloured glass roof will reject more solar energy than a light coloured metal roof.

There are three things sun light/energy of all wavelength can do. Reflected away, transmitted through, or absorbed. Of the 3 methods, only reflection will mean it is not heating something on the car up. If it is absorbed, then the roof will heat up and how much of it you will feel depends on the insulation.

A glass roof will transmit more as you can see through it. It will reflect less than a light color metal roof as it is dark. Whatever that is absorbed by the roof/glass will heat the inside up more as there are no insulation.

You can have a pretty good glass roof that blocks almost all UV, most visible and IR if it is properly made and coated, but there is no way it will beat a metal roof with insulation, especially not a white metal roof, for the ability to reject heat overall.

I don't know the specifics of the Tesla roof, but the newest tints made of ceramic or nano-carbon (?) for glass reject 60% of solar energy. I think that is ball-park about the same as a white color, so then the question becomes one of insulation.

As an aside, I would be delighted to have a car act as a green-house in the winter. It would be awesome if tint could change character by season.

 

[Snowstorm]

I want the Boeing 787 like window where you can change the tint at will.

 

[ecarfan]

I recently spent some time in my fathers new S75D with the Glass Roof. I was amazed at how effectively it controls visible light. I found I could look directly at the sun while wearing sunglasses with no discomfort, but at the same time I could see details of wispy clouded and the leaves on trees. Remarkable! I am sensitive to heat but wasn't bothered at all by whatever heat transmission was getting through the glass. It was an 80 degree day in Southern California. However he finds the heat coming through the glass roof excessive compared to his previous Tesla with the standard metal roof. He plans to have a tint added to his glass roof this week

The Model X is almost all glass and I live in Sacramento Valley, CA, where it is super hot and sunny and it is by far the coolest car I have ever owned. Every other car I have owned have been solar ovens, but MX with it's glass top is nice and cool. You will be fine. Actually, I think the glass roofs are more of an issue in cold climates, due to lack of insulation.

Note that this thread discussion is about the new Glass Roof in the Model S. While the X windshield is huge and does go over the drivers head, the S Glass Roof occupies the entire space between the windshield and the rear window and is very different from the X roof design.

Annoying - to me at least - part of the roof is when the sun directly hits your eyes when driving through the roof. Does not haapen too often, but does happen enough for me to notice. When it does happen I put on a hat and it solves the problem. There might also be an aftermakret sunshade as well you can attach to the inside of the roof...seem to recall one for pano-roofs.

As I noted above, I did not have that problem at all. People vary a great deal in their sensitivity to light.

You can find an all-glass roof sunshade for the model S here for the near 100% solution:
Sunshade for Tesla: Model-S: 2012-2017 Auto Heat Shield
But living in Houston and driving around Texas last weekend in the high 90's, the glass roof was not where the heat comes in - it's the front and back glass even with Ceramic tint. The tint let in more palpable heat than the roof - but it was negligible and the A/C even on range mode (half power) was barely running most of the trip.

Yes I think the AC can handle the cabin temp control in anything but the most extreme climates. Not sure that "All Glass Skylight Sunshade" product on the Autoshield web page you linked to will actually work on a Model S Glass Roof. I don't see how it would clip into the cavity on the underside of the roof and stay in place, and it would be very awkward to mount because the glass area is so large that you can't reach all the way around it from either the front seats or the rear seats.

I live in Hawaii and I've had my model s with the glass roof for 3 months now. When driving, the heat is not too noticeable. When its parked in the hot sun the glass is so hot it hurts to touch it even from the inside. There is quite a bit of radiant heat from it when I get inside.

You live in a very toasty climate and I'm sure the Glass Roof interior surface gets very hot. But doesn't the AC manage the cabin temp adequately?

We discussed the heat issue the other day at our local Vegas Service Center. The salesman told us heat really wasn't a problem, and that actually the glass roof cars were cooler than a comparable solid roof car. This was due to the minimal insulation and heat conductive properties of a metal roof and underlying insulation, vs the glass roof's ability to reflect all that heat and not conduct it.

Like @Snowstorm, I also call BS on that point of view. Obviously the glass roof does not block "all" the heat. Neither does the metal roof, but it blocks nearly all of it due to the air gap between the metal and the headliner and the insulation offered by the headliner.

I want the Boeing 787 like window where you can change the tint at will.

I was in that plane last month on a trans-Pacific flight and some of the windows didn't work properly. But most of them did. It was pretty neat.

 

[Zaphod]

I call BS. The glass roof maybe very good enough, but it cannot beat an insulated metal roof when it comes to heat rejection, especially not a white metal roof.

Based on my limited knowledge, there is no way a dark coloured glass roof will reject more solar energy than a light coloured metal roof.

There are three things sun light/energy of all wavelength can do. Reflected away, transmitted through, or absorbed. Of the 3 methods, only reflection will mean it is not heating something on the car up. If it is absorbed, then the roof will heat up and how much of it you will feel depends on the insulation.

A glass roof will transmit more as you can see through it. It will reflect less than a light color metal roof as it is dark. Whatever that is absorbed by the roof/glass will heat the inside up more as there are no insulation.

You can have a pretty good glass roof that blocks almost all UV, most visible and IR if it is properly made and coated, but there is no way it will beat a metal roof with insulation, especially not a white metal roof, for the ability to reject heat overall.

Glass is significantly less thermal conductive compared to metals. Even though the glass is darker, by its very nature it will not absorb nearly as much heat as metal roof, no matter what color it is.

The minimal insulation in the metal roof will be hard to combat the absorbed heat in the metal. I think you would be surprised in the performance of the glass.

 

[SageBrush]

Seems likely that AGP is the OEM for Tesla glass.
This link gives a strong hint, but I could not find performance data.

 

[EV-lutioin]

I recently spent some time in my fathers new S75D with the Glass Roof. I was amazed at how effectively it controls visible light. I found I could look directly at the sun while wearing sunglasses with no discomfort, but at the same time I could see details of wispy clouded and the leaves on trees. Remarkable! I am sensitive to heat but wasn't bothered at all by whatever heat transmission was getting through the glass. It was an 80 degree day in Southern California. However he finds the heat coming through the glass roof excessive compared to his previous Tesla with the standard metal roof. He plans to have a tint added to his glass roof this weekNote that this thread discussion is about the new Glass Roof in the Model S. While the X windshield is huge and does go over the drivers head, the S Glass Roof occupies the entire space between the windshield and the rear window and is very different from the X roof design.
As I noted above, I did not have that problem at all. People vary a great deal in their sensitivity to light.
Yes I think the AC can handle the cabin temp control in anything but the most extreme climates. Not sure that "All Glass Skylight Sunshade" product on the Autoshield web page you linked to will actually work on a Model S Glass Roof. I don't see how it would clip into the cavity on the underside of the roof and stay in place, and it would be very awkward to mount because the glass area is so large that you can't reach all the way around it from either the front seats or the rear seats.
You live in a very toasty climate and I'm sure the Glass Roof interior surface gets very hot. But doesn't the AC manage the cabin temp adequately?
Like @Snowstorm, I also call BS on that point of view. Obviously the glass roof does not block "all" the heat. Neither does the metal roof, but it blocks nearly all of it due to the air gap between the metal and the headliner and the insulation offered by the headliner.
I was in that plane last month on a trans-Pacific flight and some of the windows didn't work properly. But most of them did. It was pretty neat.

Actually, the MX roof is almost all glass too. There is the front windshield, which goes almost all the way to the FWD glass panels, which go to the back hatch glass panel. The MX is ~ 80% glass. Not as much as the MS, but close.

 

[ecarfan]

Actually, the MX roof is almost all glass too. There is the front windshield, which goes almost all the way to the FWD glass panels, which go to the back hatch glass panel. The MX is ~ 80% glass. Not as much as the MS, but close.

I am aware. I have had multiple X test drives. I stand by what I wrote: "While the X windshield is huge and does go over the drivers head, the S Glass Roof occupies the entire space between the windshield and the rear window and is very different from the X roof design."

 

[Topher]

While comparing heat performance can be done from first principles, I would need to know a lot more things before I would undertake the calculations. Including emissivity of the various surfaces, any coatings on the glass including exactly which surface, thermal mass of the various components, reflectivity of inside surfaces, and so on, plus some significant amount of computer time.

It would probably be quicker and easier to wait for the car, and do an empirical test. Guessing without knowing those engineering specs is not going to be productive. Sorry.

Thank you kindly.

 

[CameronB]

I have the all-glass roof and I have no issues with heat nor the perception of being bombarded by many UV rays. I have little hair and still no problem at all.

What IS a problem is the rest of the glass - particularly the windshield. But also the side windows. I definitely can feel uncomfortably amounts of heat coming from everywhere except the glass roof. Looking forward to a good tint job next month to remedy this.

 

[Snowstorm]

I am getting 3M crystaline 70 on all windows (except glass roof) and crystaline 90 on the windshield. Very light on the tint, but claims to block about 50% of solar energy. Will let you guys know how it goes when I pick it back up.