Luxwall insulated glass
Hi GBA, A former colleague just asked me about Luxwall Enthermal glass https://www.luxwall.com/, which I had never heard of, so I thought I’d ask if you all had heard of it. Here’s the manufacturer’s website description: Our next generation product solutions deliver between R-18 and R-21 thermal insulation – outperforming current glass and window product offerings by up to 4X. Enthermal™ high-performance glass can be customized for climatic regions (Low-E coating selection) and window sizes (glass thickness selection) to maximize return on investment. Enthermal™ is a uniquely low U-value glass that can be produced in a wide array of configurations to enable drop-in replacement of single and double pane insulating glass units.
Patrick
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I do not know, but....
Searching for information one finds business blogs, paid advertising, instagram etc, rather than any serious information
5 year old company
Vacuum glass has been around in theory for a while
I haven't heard of them either, but they just completed a $51 million series b so they most certainly are a serious company. Per https://www.luxwall.com/luxwall-open-new-manufacturing-facility/ they are in the process of building a factory, so if they are able to get a quality solution into production that could be a gamechanger for vacuum insulated glazing.
For those interested:
Crunchbase info: https://www.crunchbase.com/organization/luxwall
CEO: https://www.linkedin.com/in/scott-thomsen-a1009996/
Company Linkedin Profile showing 79 currently registered employees: https://www.linkedin.com/company/luxwall/about/
I dunno guys, not trying to be a downer, but I fail to see evidence that they have produced anything actually on the market, and they certainly have not been around long enough to have a warrantee history.
Gusfhb, you're not being a downer, I'd bet you're right and they've never sold a single IGU.
You have to remember that VC backed companies work very different than traditional businesses. Revenue is a distant second priority to creation shareholder value and positioning the company for the necessary funding rounds and eventual exit (IPO or acquisition). Presumably they've been focused creating IP and manufacturing/production engineering for their initial factory.
Can someone explain in lay-men's terms what produces those R-values?
Are vacuum glass units more vulnerable to failure than the ones we use now?
Malcom, it's the same concept as a vacuum insulated thermos, in a space devoid of matter you can't have heat transfer through conduction or convection. This still leaves radiation, no doubt augmented with low-e coatings, and the relatively small amount of conduction through the perimeter and required pillars to keep the panes separate.
It could be a total game changer if they can bring it to market at a decent price and believable durability/lifespan. VIG has been around for a while with no major successes, so I won't be holding my breath.
I don't know about vulnerability to failure, however the consequences would be very different. With a failed IGU you would lose the benefit of the inert gas, if present, and have fogging that is mostly aesthetic. A failed VIG unit would essentially become a dual pane window with inadequate spacing, causing a dramatic reduction in thermal performance.
bcade,
Thanks!
A perfect vacuum has no thermal transmission
But imagine trying to keep a 28PSi differential between the inside of the IGU and the outside
tough
as yet unsolved
gusfhs,
28psi. Yikes!
14psi is atmospheric pressure. Why double?
1 ATM is as high as it can get, yes. Would have to go into an autoclave to be any higher, like we often do with molded composite parts (vac bag and then place in autoclave for additional pressure).
You are correct of course, just misremembering my AC gauge which seamlessly transitions from PSI to inHG
Glass is a polymer material that deforms over time so to overcome the constant atmospheric pressure on the outsides pushing in there are tiny little clear standoffs arrayed across the inside to keep the two panes apart. The sealing at the edges is the critical part and has been the downfall of the technology thus far but apparently Luxwall has some unique experience in this domain that will potentially achieve a permanent seal. My understanding of the tech is that you need a really deep vacuum to really stop convection. For a permanent seal the edges of the glass need to be fused i.e. the glass edges get melted together which means a lot of heat and thus distortion and internal stresses that then have to be released. One benefit is that the VIG units can be made quite thin, just over 1/4" and could thus replace single glazing in historic buildings.
Glass is classified as an amorphous solid rather than a polymer, but I do agree that the potential problem with vacuum glazing is both long-term edge seal as well as needing structural support between the lites to keep the glass panes separated.
We had a rep from VacuMax come through our office relatively recently...
https://www.vitroglazings.com/products/advanced-glass-applications/vacumax-vacuum-insulating-glass/
They've got it highlighted on at least one built project on their website. I agree with all above that it seems too good to be true, but it's a darn interesting idea if it can be pulled off successfully and can remain sealed for a reasonable length of time. The sample they left in our office is pretty slick, and you can barely see the standoffs that separate the glazing panels.
Does the glass have to be pre-curved to compensate for the vacuum pressure differential? Or is the glass thick enough that concave lensing doesn't become an optical distortion issue?
Nevermind, I see the micro support pillars on the VacuMax stuff now. That explains it.
Once you see the pillars in a VG glass package, it's almost impossible to "unsee" them whenever you look through the window.
While probably not a big problem for most people, it might be a deal breaker for some.
Oberon,
I've always been curious to see how prominent the pillars are in person. That makes me wonder if they might have an unintended positive impact on the ~billion lethal bird strikes in the US every year. Presumably not much, but anything would be an improvement.
Oberon & bccade,
Check out the photos of our office sample...
You can definitely see them (and I totally get how for some people would never be able to unsee them), but they're fairly subtle depending on what's behind the glass, viewing angle, lighting, etc. The sample is from VacuMax.
There is a definite green tint to the glass; I assume this could be dealt with via a different glass spec?
I have had the opportunity to see examples of vac glass from a few different manufacturers - even had a chance to see a couple "under construction" - but haven't seen the Vitro version in person. Looks pretty good in the pictures, thanks for those.
Per the green tint I am guessing that the samples probably have a lowE coating inside the vacuum space. Since Vacumax is a Vitro product I am also guessing that it might be Solarban 70 a triple silver coating, also from Vitro, that has a distinct green appearance.
I don't know if there is any technical reason for using SB70 (again emphasis on guessing) if they did for the samples, but if there is no technical necessity then the Solarban family of coatings does come in a variety of shades and hues so seems like there should be options in that area.
Can confirm, the coating is Solarban 70. Not sure if it was required for some reason, or if it's just what they went with for samples.
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bccade,
I have no idea if the pillars would deter bird strikes but would be great if they did. That is a really interesting idea that might even be an added selling point for some people.
Our local birds seem to strike when the lighting conditions make really good reflections, so I would imagine the pillars are probably obscured behind the reflection.
Thanks to all of you for your thoughts and info. This is a great community.