Why any tint? Anything that you put on is going to lessen the passive solar in and Michigan, you are spending more or heating than cooling. Only reason I could see for some tint would be if you had some solar control issues.

Are you getting new windows? How old are your current windows? Are you aware that new windows come standard with LoE-272 coating? LoE (low-emissivity) coating is designed to reflect heat. Windows made with LoE glass repel ultraviolet rays that generate heat during the summer but absorb UV rays and let heat in during winter.

There are several LoE levels - if you lived in Arizona for example, you'd want the stronger LoE-366. But the standard LoE-272, appropriate for Michigan, is transparent. There is no need whatsoever to add a tint to your glass, and I think it would be a big mistake. It would make your house look odd from the outside, and would be a huge deterrent if you ever want to sell the home. Windows are expensive enough and permanent enough that you won't be able to change them if you don't like the tinting effect.

The builder suggested we tint windows because our interior would fade. There is little to no sun in winter in Michigan so it won't help with any of our heating bills to leave them "naked", most of our winter days are grey and gloomy. The reason for tinting is to reduce glare and block more UV rays than the basic builder grade window can do. The glare is so intense I have to wear sunglasses in my house. I like my views so, I'd rather not cover that up.

I don't know what windows you are installing, but really, LoE-272 is standard in new construction, even on "basic builder grade". Your builder knows that. The LoE coating will be enough for the Michigan sun, and will prevent fading of floors and furniture. I would ask him about the LoE coating on the windows, and ask the name of the windows manufacturer if it were my new house and my money.

The tint is a bad idea as aready said above. If you want to pay more to your builder for an un-needed and unsightly tint, then go for it. You asked this forum, and received answers.

"The builder suggested we tint windows because our interior would fade."

Interesting theory but not completely correct. I am almost afraid to ask what bran d window he suggests to go along with the tinted glass?

We have Jeld-Wen. It's a new build and our confidence in what the foreman in charge tells is not that great. Either way, the windows still need something to block the intense amount of light that comes through without hiding/hindering our views in the summer and let in optimal light during the winter, when it's almost always grey and cloudy out.

Lo-E 272 as a standard should be perfect for your application. Unles you wanted to step up to a triple pane but I am not certain Jeldwen vinyl even offers that and the upcharge frm a developer may put it ouf of range as well.

Tina, you may have been given some questionable info by your builder. As the others have remarked above, the Low-e glass is what will provide both increased energy efficiency as well as offer some fade protection. Most glass with or without the low e will have a slight green tint. There is not a compelling reason IMO to go with a gray or bronze tint here. It will likely just make your home darker with no other real benefit.

There is a little bit of ambiguity here. On one hand, it sounds like these windows are already installed, and a tint application is being considered. On the other hand, a "new build", and a "foreman" are mentioned, insinuating that this is something still in process, and the tint under consideration would be from the factory on these new windows. To clarify, if you have any choice in the matter and the windows are not yet installed, you should be getting windows with a minimum of low e and argon. Any reputable builder would be installing that in MI, even with a budget window. If that is the case, and you have not yet experienced the windows in the home, I believe that they will perform to your liking, and bronze or gray tinted glass would not have much benefit.... IF these windows are already installed and you are unsatisfied with the performance, THEN perhaps an aftermarket film could be in order.

Tina, help us out a little on the details. :)

Umm Dude she said she had 8 large windows in the OP. Less Monster ok? ;) A low emission film coating on her existing windows will retain that heat in the winter and stop heat and fading uv to a great degree come summer. And look rich.

I'm not sure what any of that means. I'll ask my teenage daughter to translate.

Again some clarification would help. The third post by the op references a new build and the project foreman, suggesting that these windows may not yet be installed.

Low e windows do stop infra red wavelengths usually in the nanometer range of 780-2500 by design. Whether they exist or not, and whether they are low e or not, they will not be stopping UV light which is on the other side of the visible spectrum <350nm. Easy fix with film. Oh and Monster=caffiene.

If you read Tina's posts, they're a bit confusing. First she is living in the home with the windows and furnishings, then it's a new build with ongoing conversations with the foreman. Did the foreman make the sunglasses comment, or is that Tina's opinion? Also, her posts ignore entirely what WoW and I wrote, as if our posts were not there. I am wondering if the foreman/builder really is the poor communicator here.

Tina should just get sheer blinds on those windows, finished. She said she wants the view, but if the sun is so blinding she needs sunglasses inside, she can't look out at the view anyway. Sheers will filter the sun, and have a small stackback, so that on days when it's cloudy, or not in mid-day, the view can be enjoyed. Has Tina thought about what happens at night, when there is no view? During the long and cold Michigan winter, I cannot imagine having 8 large windows with no treatments on them; sheer blinds would be subtle enough not to bother anyone. And, unlike tinting, they are removable if you want to do something different, and won't be weird-looking from the outside. You can have all 8 window shades controlled by a clicker, so that they go up and down in unison and effortlessly.

Trickyputt, standard low e will block some uv rays and offer fade protection. It looks like you edited the post where you had recommended that specific aftermarket film, but I agree with the premise that solar control films can and will offer BETTER fade protection than standard low e, albeit with drawbacks as well. That said, again, different glass could be sourced in the initial window purchase if that is still on the table. Something like guardian's climaguard spf would be a superior solution - and cost less- than an aftermarket film applied to new windows.... It also remains to be seen what the OP's weighted priorities are here, and exactly what the current situation is.... I think our speculation is taking the conversation off course a bit at this point...

Thank you all for taking the time to provide input. Here is some clarification; we had the house built this year, March 2017. We just moved in. Unbeknowst to us, we picked the worst builder in the area. (Yes, we tried doing our research but were not successful.) Therefore, the quality/workmanship of our house is not so great. Bottom dollar is key for the builder. Our windows fall right into that category.

We've looked into sheers and unfortunately, it's not an option for us. We are considering having Vista window film installed with the choices being grey or bronze with variant degrees of darkness, glare reduction, heat reduction. Right now, our main priority is to keep some, not all, of the intense glare out while still maintaining our view to the outside. We love natural light but this much is just blinding. All Vista window films come with a 99.9% UV reduction.

So, my concern is with the aesthetics of the window film color, grey vs bronze.

I hope that cleared things up a little.

Cleared it up immensely Tina! Sounds like it's more of a design question at this point... which makes sense given the title of your post. I agree with your initial sentiments that the bronze may be a little "warmer" than the gray. Ask the vendor if they have a showroom with some installed, or at least some pictures etc where you can get a better feel for the colors. Beyond that, the only thing I'd suggest would be to limit the film only to the areas where this is a concern for you (with some thought to aesthetics of course), because WOW's initial comment on the solar gain is still valid even if you don't get much sun. I'd imagine that our weather here in Milwaukee is similar to yours.... You did mention only one bank of windows, so perhaps you are already on top of that :)

Just be certain that you won't void your glass warranty with the film. Film has been known to cause heat buildup and the seals to failure prematurely............

Actually, what I do see from time to time is a one window failure on film installations, not all of them. That means it was weak somehow from the factory. The film companies have a film to glass application chart to follow, and the factory warranty on films from the larger companies covers 3 year thermal seal and 5 year glass breakage if you do not have a warranty, and can replace or supplement your existing warranty, which ever is better. The main difference in seals is speciality applications such as hurricane rated glass which requires a more tenacious frame as one might imagine. The seals I see regularly on low e or regular double pane are the same seal. The low e windows around here in Birmingham are stopping 40 degrees across the glass where the regular glass only stops 20 degrees. Any coating or film to improve that is a big plus.

You selling window tint tricky? Seems that way. Doesn't have much application value up north, and like millworkman said, I'd worry about voiding manufacturer warranties. Not sure about these "tenacious frames" either, or how that would affect seal failures. Snake oil imo.

The Vista window film company will match the Jeld-Wen warranty. The window film also helps retain the temperature in the home, keeping it cooler in the summer and warmer in the winter - according to the manufacturer.

@Homesealed, I wish the vendor had a showroom! He did tell me that the grey is more popular than the bronze but didn't have a reason for it. It's just what people are used to I suppose. He, however, has bronze in his own home.

Actually yes I have 3 tint companies in different counties. I have been doing this through college, actually it paid my way so I did not have to borrow. And I disagree with you about not needing it up North, as the low-e works to retain heat, but the process of emissions, and the super smooth finishes necessary to accomplish such mechanical designs are often lost on people who started working in the the back and made their way to the front counter. I know. I hire people like that and actually have to argue with them to understand basic concepts, but in this case of emissions it works exactly like a lightning rod which is not too complicated for us here in the age of google.

Sounds like you have your bases well covered Tina.

Trickyputt, what do you recommend for the Seattle area? We want to enjoy our small water view, but have UV and glare protection? Thank you.

Teaka123–did you end up doing anything?

I see no one responded.

I just found this thread today as I am also now looking at bronze or gray tinted glass for new windows/doors in our renovation. I’m currently considering bronze-tinted cardinal glass on impact resistant hurricane glass. We live in sunny Fort Lauderdale, the glare is shockingly painful a good amount of the year. The bronze tinted glass from cardinal reminds me of that sepia film color in photography from years ago. To me it feels more warm/homey than gray.

Edith Keeler,

City on the Edge of Forever fan??

Bit of trivia, tinted impact glass with PVB interlayer is likely going to use a tinted interlayer rather than tinted glass, but if using SentryGlas (SGP) interlayer is almost certainly going to use tinted glass. You shouldn't be able to tell the difference, but just how it's usually done.

When you get a tinted glass IG unit (impact or not) that also includes a coated lite, there is the question of coated lite versus tinted lite location as installed in the window. In other words which one faces outside and which one faces inside.

Both aesthetically and performance-wise it does make a difference. For example placing the LoE coated lite interior while the tinted lite is exterior is going to trap a lot more heat between the lites than will happen if the coated lite is outboard.

This is true regardless of whether the tinted lite is part of a lami unit or just a monolithic lite. The temperature can be extreme and can result in seal failure or even broken glass.

If the window company is using Cardinal glass and their IGU system, Cardinal can determine if the glass used in the window should be heat strengthened prior to building the IGU in order to withstand the increased stress due to trapped heat. Cardinal IGU IGU/spacer system is very robust and should be able to handle the heat without issue. Glass breakage is the bigger concern, but again heat strengthened or tempered glass eliminates that risk.

Per aesthetic, that's really a personal preference.

Some years back I was involved in a situation where a home on the California coast had a wall of bronze tint and LoE windows facing the ocean in a standard IGU (not impact) configuration. Unfortunately the glass looked different; two different colors and very noticeable.

Turned out that the window company had installed the IGU's with about 2/3 tint outside (correct) and 1/3 tint inside (incorrect). The window company stated that the 1/3 of the IGU's with tint inside were built "backward" which was not true, they were all correct and it was the window company mistake on installation of the IGU's into the sash.

The fix was to deglaze the 1/3 incorrect IGU's, turn them around and reglaze. Unfortunately for the window company turns out that the homeowner really preferred the look of the LoE outboard and bronze inside, which was not the original plan, so that the window company actually ended up deglazing and reglazing 2/3's of the IGU's rather than the original 1/3 that were initially "wrong". Thus my comment on aesthetic preference.

Keep in mind that any window that adds tint to LoE is going to be dark, and I agree that bronze is softer and warmer than gray.

Also for reference, tinted glass be it interlayer or glass in an impact product, or just regular tinted glass, has visible light transmittance of 52% for bronze, and 44% for gray. There is also a 28% gray for specialty requirements.

As an aside, wish I had seen this thread when trickyputt was comparing films to LowE glass, that would have been an interesting discussion.

Oberon476,
You are the ONLY person to get or call me out on my Star Trek reference! I didn’t think it was possible for me to be MORE impressed by you and then BAM, you make it happen!

I have in my hands grey- and bronze-tinted glass samples as we speak, I think they’re PGT or CGI, (not Marvin). There’s two lites that from the side appear to my untrained eye to be laminated. One lite looks to be clear glass, the other lite appears to be tinted glass. Both PGT and CGI use PVB. I can’t remember if they even offer SGP, but I don’t think they do.

Thank you for the response, information, and trivia—now I also have glass production interlayer tint questions to get answers to. I’d rather know than not.

Is every clear glass lite made nowadays with a certain level of LoE? That’s one question I haven’t asked anyone yet.

LoE366—that one for me is ruled out. Courtesy of the previous the owner of our home, we currently have three sets (nine 3’ panes) of vinyl circa 2013 CWS argon IGUs with LoE366. I’ve lived with the odd green hue inside the house from the 366 and the vinyl for 6 years and I just can’t anymore. The vinyl with our heat and humidity expands, contracts and makes noise. I guess I’m one of the few people affected by being able to see the green hue it gives off?

If I do get a bronze tint, 366, he won’t be involved. I’ve seen the LoE366 with grey and bronze tint, WAY too dark for me (and there’s still that greenish “meh” dull hue to it.

With the benefit of your input, now I’m down to bronze or old-school clear on the glass color. The glass will be lami impact, no Argon/air IGUs. Give me sound reduction, increased strength/security of lami, but I’ll pass on the potential seal failure and sacrificial outer pane of the IGU. (We had two units replaced due to seal failure)

I’m 99% sure I’ve decided to go with Marvin Coastline for our reno(hope I’m making the right decision). So, Monday/Tuesday I’m headed up to the SIW showroom in Delray to touch/feel all the products and torture the people who answer questions and determine who makes their glass, how it’s tinted and what exactly it will look like. I’m pretty sure Marvin uses Cardinal, but I’ll find out.

I know Marvin acquired SIW Windows & Door’s assets in 2019 and took over production, but there’s still an “SIW Solutions” in Delray. I think they’re contractors/installers. I’ll figure it out when I get there.

I know Marvin offers PVB and SGP and multiple glass thicknesses on their coastline products (more decisions), but I’m torn on the interlayer. We currently have 95% impact on our house, I’m fairly confident they’re all PVB laminated.

I really enjoy and can attest to the noise reduction property of PVB. SGP, I’ve read, is superior to PVB in strength and slower-to-yellow benefits, but that in sound reduction it’s not as good as PVB. If that is true and I’m gonna get noticeably more noise with SGP, then I think I’d have to stick with PVB. I love not hearing the drama of my neighbors.

Now I’m gonna read your last post three more times and make notes for my field trip on Monday…

…and if you ever do debate the merits and values of film and LoE glass with trickyputt, give me a heads up, I want the opportunity to make popcorn first, k?

;)

Edith Keeler....must die...

Great episode from an amazing series. We don't proper acknowledge how brilliant Roddenberry was.

HAHAHAHAHAHAHA!! Nice to know I’m not alone ;)

They don’t recognize Roddenberry’s brilliance and vision, but we do!

The square multicolored floppy disks and the round silver disks that looked like CDs, that kind of thing still freaks me out. Which came first/chicken egg kind of thing….

And anyone not familiar with the episode may be really wondering what WoW is planning after his reply up there......!!

Easiest way to reply I think.....

"I have in my hands grey- and bronze-tinted glass samples as we speak, I think they’re PGT or CGI, (not Marvin). There’s two lites that from the side appear to my untrained eye to be laminated. One lite looks to be clear glass, the other lite appears to be tinted glass. Both PGT and CGI use PVB. I can’t remember if they even offer SGP, but I don’t think they do."

My earlier comment about tinted interlayer versus tinted glass were meant specifically to Cardinal/Marvin. Sometimes I need to remember to clarify...PGT, CGI, others might or might not do it that way. Sounds like your samples are tinted glass rather than interlayer.

Both PGT and CGI used to offer SGP and honestly I would be very surprised if they still don't, but I have been out of the loop for a few years so would have to make a few inquiries to know for sure and if that was important; which I suspect it isn't based on what you said a little further down in your post.

"Is every clear glass lite made nowadays with a certain level of LoE?"

Nope, although hardcoat LowE is applied during the float using a process called Chemical Vapor Deposition, softcoats (way more common) are applied after the fact in a process called Magnetron Sputter Deposition that is totally separate from glass manufacturing.

"I guess I’m one of the few people affected by being able to see the green hue it gives off?"

Although the vast majority of people either don't notice or aren't bothered by it, there are some folks like yourself who are really bothered by the color shift. There are alternatives available.

"With the benefit of your input, now I’m down to bronze or old-school clear on the glass color. The glass will be lami impact, no Argon/air IGUs."

This one is a bit more involved. I am seeing that you are getting monolithic impact glass and not IG units, either bronze tint or clear. I am going to reply based on that idea.

"Give me sound reduction, increased strength/security of lami, but I’ll pass on the potential seal failure and sacrificial outer pane of the IGU. (We had two units replaced due to seal failure)"

Monolithic laminated glass is potentially a real plus for sound reduction, but is even better (potentially a lot better) when used as part of an IG unit rather than monolithically. I won't go into the details here, but can in separate post if you want to know more of my thoughts on that.

Also I am going to strongly recommend that you reconsider the idea of not using a LowE coating in your window glass regardless of IGU or monolithic. I am not going to suggest advantages of IGU over monolithic glass windows specifically because of where you live, but I firmly believe that using an IGU is better than not. I also believe that in your environment monolithic impact glass will work quite nicely for you - but I am going to suggest that you consider using not only one but two LowE coatings in the construction of a monolithic impact glass window.

But due to time constraints and the length of this reply already I will be back a little later.

Part 2

LoE coatings can be applied to either the exterior or to the interior of a laminated glass unit. When applied to the exterior of either a lami or single glass sheet there is no energy performance or aesthetic difference between a lami lite or a single monolithic lite, but when applied to the interior of a lami unit, against the interlayer, the U-factor performance of the coating is negated while the SHGC performance remains the same as an exterior application.

This was a good deal for folks in the deep south who wanted impact glass because it meant that they could block solar heat as well as get the benefits of the impact glass. But even in the south there are times when a little bit better U factor was a good thing, so impact glass manufacturers began adding a hard-coat LowE, typically Pilkington Energy Advantage, to lami surface 4 (the surface you can touch inside your home) to improve U factor performance. Eventually surface 4 sputter coats, such as Cardinal i81 and i89, were introduced for surface 4 application with slightly better appearance and performance over the pyrolytic hardcoats in that application.

Once again, if you are curious about this option let me know and I will go into more detail, otherwise just there for your consideration.

"I’m pretty sure Marvin uses Cardinal, but I’ll find out."

Yep, Marvin impact glass does come from Cardinal, as does about 95%(+) of all their glass.

"I know Marvin offers PVB and SGP and multiple glass thicknesses on their coastline products..."

That is correct.

"I really enjoy and can attest to the noise reduction property of PVB. SGP, I’ve read, is superior to PVB in strength and slower-to-yellow benefits, but that in sound reduction it’s not as good as PVB."

That is also correct. SGP is 5x more tear resistant and 100x stiffer than PVB, but it has basically no sound performance improvement when compared to regular glass. If you want sound performance ensure that you get PVB.

Per yellowing, neither PVB nor SGP are going to noticeably yellow in your windows. That's something I wouldn't be even remotely concerned about.

"…and if you ever do debate the merits and values of film and LoE glass with trickyputt, give me a heads up, I want the opportunity to make popcorn first, k?"

I will reserve you a front row seat!

Safe trip to visit the Marvin distributor, and pay attention and watch out for small trucks when crossing a busy street!

Thank you SO MUCH for all the information, validation, and confirmation.

In recent email conversations with an installer sales representative, she has told me outright that LoE366 with or without tint is my only LoE option, so I'm going to try to speak to people up in Delray, see if I can get an answer on Marvin Coastline LoE and tint options here in South Florida with two soft coats of LoE. Maybe I wouldn't notice if it was only two coats with a bronze tint? Dis... we do not knowdis.

I understand and I concur, there is a palpable definite advantage to the LoE IG units, I have them currently in two sets of SGDs across the east-facing wall of our house, 3 panes on the north end and another 4-pane SGD toward the south end. When you physically compare the heat on the inside of the glass between 8am and 11am, the IG units have minimal heat transfer. (There is still warmth while standing near the glass from visible light, I guess, but the dogs like it.) The older clear laminated monolithic glass (hope I'm using the right terminology) without LoE (why that window was not replaced by the previous owner, wedonotknowdis), the incoming heat is clearly stronger during direct sunlight. From my rookie experiments and through living through summers here with the two different products, the IG units with LoE366 are superior and do their job, hands down, no doubt.

U-factor isn't a thing here. It's warm in the winter, warmer in the spring, hot in the fall and unbearably, brutally, astonishingly hot in the summer. Keeping the heat inside is only potentially needed maybe 3 days a year, and that's if we're lucky.

You know it'll be WoW waiting for me in Delray behind the wheel of that truck! ;)

Did you know that the U factor given for windows is technically the winter U factor and that there is also a summer U factor (but that is not generally published)? Honestly I don't know how often that its even computed, but it is a real thing.

Obviously when it's -30 outside and 70 inside that's a hundred degree difference and U factor is pretty darned important. But what if it's 50 outside and 70 inside? Twenty degrees difference just not a big deal, even a single pane clear glass is going to do well in that situation.

So what about 90 outside and 70 inside? Again not a big temperature difference, but nature doesn't care, nature is still going to try to get those temps equal by moving some of that heat inside your home. So even though it's not comparable to the difference -30° to 70°, when you want your home at 70° and nature wants it at 90° any U factor improvement is going to help affect your indoor comfort when it's unbearably, brutally, astonishingly hot in the summer outside. You might even save you a couple bucks when you don't have to torture your AC to work extra hard when you are trying to sleep at night.

Without doubt in a cooling dominated climate blocking solar heat is by far the more important consideration, but we need to remember that heat also moves by conduction and convection, so for best results it can be important to address those areas as well as the all important solar radiation.

That's where adding the surface 4 coating to monolithic laminated glass came from. The low solar gain coating between the lites blocks radiant heat gain through the glass while the surface 4 (lower U factor for monolithic ) helps keep the 90° ambient heat outside where it belongs and not inside messing with your calm.

Your grasp of the technical terms is right on the money.

WoW's not only a really smart guy, he's also a really big guy. So if it was a little truck he might not fit inside, he might have to carry it.

Oberon, you make-a-me laugh!

Because you know what WoW looks like, now I'm thinking there's a club and I have to find a way to join.

I grasp the concept of U factor a bit more now. I know by code the windows/doors we install have to meet a certain U factor number. If the window/door product I choose doesn't meet code, I will HAVE to put tint or LoE to make it meet code. I also know because we are not putting an addition, the bar is lower on that requirement.

Now realizing that U factor relates to keeping the 90-100 heat outside the house. I did not realize LoE assisted in doing that...very interesting. I was looking at acquiring thermally broken windows/doors. WinDoor (company in Orlando now also owned by PGT) makes thermally broken frame window/door products; however, if memory serves, they're not HVHZ zone of Florida in which we reside code compliant/thermally broken doesn't pass code. Hopefully the fact that I chose white aluminum frames, that will help by reflecting some of the heat away since I can't get thermally broken.

We're sealing the attic space/closing the vents, removing the ceilings and putting that new-fangled foam in the attic/under the roof, the stuff that hardens and is supposed to be the funk phenomenon (I don't know the name of it). We currently have a subpar amount of the old-school fluffy pink stuff that has become useless and broken down with time. We're also adding insulation to the west, south and east-facing CBC/masonry walls because NOTHING holds onto heat longer in this house than concrete block and the concrete roof. I feel like doing those two things will make a HUGE difference in our AC runtime. (Hopefully I'm not repeating myself, I have CRS more and more nowadays)

This surface-4 coating to monolithic laminated glass, that means the coating is on the outside surface of the glass weathering the elements. Surface number one faces the interior of the home, surface two faces (hypothetically) the PVB interlayer, surface three is the exterior lite that faces into the PVB interlayer, so surface four faces out to the sun/heat; did I get that right?

Squirrel moment--

I have noticed that Marvin's Multi-slide SGD is 9/16" thick using a SGP interlayer.

I've also noticed CGI's Estate Series SGD is 1/2" thick using a PVB interlayer.

Marvin's glass is a teensy bit thicker with an SGP interlayer (allegedly bomb resistant, I've read).

I'm guessing Marvin uses the SGP interlayer to make the glass stronger.

1-doesn't that make Marvin's door more qualified against hurricanes?

2-Will the less-than-stellar ability of SGP to reduce outside noise to the degree that PVB can reduce noise be noticable? Is it a game changer?

3-Seeing that both CGI and Marvin use the same Cardinal glass, the Marvin frame is allegedly on par or stronger than CGI's, do these facts make Marvin a superior product?

(Feel free to ignore this question publicly and PM me, if you are so inclined.)

Marvin also has this SUPER COOL interior-installed retractable screen. They don't offer it in the Coastline product yet to Floridians, an oversight I'm trying to rectify right now with their people.

Check this out.

Retractable screen -- sorcery!!

Yep, coatings do contribute a great deal to U factor performance, and as a simple example of how much I am going to offer a few numbers, but in R value not U value because frankly it's easier to visualize.

If you don't know this already, R = 1/U and conversely U=1/R. They are inverse of one another. R value means resistance to heat flow and U value is a measurement of actual heat loss.

Window U-factor of 1 = R value of 1, while window U.5 = R2, U.33 = R3, U.25 = R4, and U.20 = R5....and so on.

So talking about glass and windows in R value because it is simpler to visualize:

A single lite of clear glass = R1

two clear lites in an IG or single with a storm window = R2

three lites in any configuration = R3

So far pretty simple, but what happens is we add LowE coating and argon?

two lites with a basic LowE coating = R3

three lites with two LowE coatings on two different lites = R5

two lites with LowE and argon = R3.5

three lites with LowE on two lites and argon in both airspaces = R6

These numbers are very general and in actual practice they will vary based on the coating used, the level of argon fill, and even glass thickness and the width of the airspace, but they are reasonably accurate for illustration. Also these are glass-only numbers and not window performance numbers which add additional variables.

"This surface-4 coating to monolithic laminated glass, that means the coating is on the outside surface of the glass weathering the elements. Surface number one faces the interior of the home, surface two faces (hypothetically) the PVB interlayer, surface three is the exterior lite that faces into the PVB interlayer, so surface four faces out to the sun/heat; did I get that right?"

Nope, surface 4 coating means that the coating is on the inside of the home and surface 1 is outside. This is true for both IGU and laminated.

Wanna be really confused? It isn't uncommon for IG folks and/or window folks to refer to lami as having two glass surfaces and not 4, so that they would refer to the lami in an IGU as being either surfaces 1 and 2 or 3 and 4 depending on orientation in the window. Usually not a big deal unless the LowE coating is between the lami lites, then try to explain it. Correctly an IGU with a lami component should be stated as having 6 glass surfaces, but reality is that very often it's not.

And before I forget, NEVER use a surface 4 coating on a monolithic laminated lite when the outer lite is tinted because surface 4 is going to get HOT, I mean actual potential to hurt someone hot. And that window is going to be like a space heater in the room, it's going to radiate all that excess heat into your nice air conditioned living space.

When considering using a surface 4 coating to improve U factor performance for a mono lami, ONLY consider it if the lite facing outside has a low solar heat gain coating.

"Squirrel moment--

I have noticed that Marvin's Multi-slide SGD is 9/16" thick using a SGP interlayer.

I've also noticed CGI's Estate Series SGD is 1/2" thick using a PVB interlayer."

Within the glass industry and lesser extent the window industry, glass is measured and referenced in mm rather than in fractions of an inch for precision, although even people within the industry will refer to fractions at times usually when not being technical.

For example, common, everyday, thicknesses of glass from a float might be 1.6mm, 2.0mm, 2.2mm, 2.5mm, 2.7mm, 3.0mm, 3.1mm, 3.9mm, 4.7mm, 4.9mm, 5.7mm, 5.9mm, 6.0mm....and so on. Imagine converting those into fractions and trying to keep track.

If a window company wanted 1/8" tempered glass for use in an IGU, for example, then they would likely be getting 3.1mm, but if they wanted ordinary annealed glass, then they would probably receive 3.0mm.

I could write pages about why thickness differences but suffice to say it can be simple in some cases and complicated in others. And some of those glass thicknesses directly relate to use with laminated glass.

"Marvin's glass is a teensy bit thicker with an SGP interlayer (allegedly bomb resistant, I've read).

I'm guessing Marvin uses the SGP interlayer to make the glass stronger."

Here's a little secret for you, although glass is referenced in mm, interlayers in North America are usually referenced in decimal. Don't ask me why, that's just how it's done, but referencing interlayers in mm is becoming more common. This is why you can have a lami make up that's listed as 3.0mm/.090"/3.0mm. Weird but how it's done, but there's more.

PVB comes in thicknesses of .015", .030", .045", .060", .090", with .090 generally used for impact products, but not always. PVB can also be stacked, for example adding two .060" for a total of .120".

SGP comes in thicknesses of .030". .035", .038", .063", .095" and .100". So the reason why two laminated glass lites one with PVB and one with SGP aren't the same thickness is because SGP is slightly thicker than PVB. I do need to mention that there is an update to SGP since I retired and I don't know what thicknesses it comes in.

Per bomb resistance, much of what I know in that area is very proprietary and not something I would post in public, but yes that is an option, but far from the only one, and I know some of them would surprise you.

SGP has 5 times the tear resistance and is 100 times stiffer than PVB, but that isn't the whole story about how it functions as an impact resistant interlayer. Depending in the window size, aspect ratio, frame and sash materials, so on, sometimes SGP is the better choice and sometimes PVB is the better choice. They both have their place.

1-doesn't that make Marvin's door more qualified against hurricanes?

Not necessarily, but I love SGP tear resistance in high wind situations.

2-Will the less-than-stellar ability of SGP to reduce outside noise to the degree that PVB can reduce noise be noticable? Is it a game changer?

That's your call, but SGP does virtually nothing for sound resistance while PVB is used in sound and recording studio glass.

3-Seeing that both CGI and Marvin use the same Cardinal glass, the Marvin frame is allegedly on par or stronger than CGI's, do these facts make Marvin a superior product?

Again not necessarily. Wood, vinyl, fiberglass, aluminum, have all been certified to hurricane codes, both Miami Dade and ASTM E1886 and E1996. Some sash/frames are stifff as heck and never move, others flex like crazy but stay in place. As long as they meet code that would not be my concern.

Do I like Marvin better? Yes I do, but that has to do with a lot of other reasons, not just the material they use for their sash and frames.

My experience? Tinting windows doesn’t work. If you are worried about heat and fading invest in good quality properly lined windows treatments .

Agreed that tinting windows doesn't work very well, but LowE coatings do block solar heat gain and UV, especially (UV) when combined with laminated glass.