Historic window glass- why insulated glass needs a major redo! 

Oh, boy. What has Richard gotten me into now? Soo much good info, such little time.

I love your 100 year concept. I've been in the service and trades and my mantra has always been if it won't last 50 to 100 years... I don't want to do it.

This channel is amazing, incredibly unrelated. Treasure trove of information about buildings things beautifully, the right way, all with an appreciation and admiration for older forms of architecture / ways of building.

Hi Brent, just wanna say thank you for making all this information accessible not just in this video but all the information you provide. I personally love it and as you say makes me want to build better. I'm a traditional trained joiner from Scotland, currently building in Australia and you have been an inspiration in the best way I can imagine and an eye opener for me. Thanks again and please never stop

OH MY GOSH...!!!...One of the top debates I have with Architects, Contractors, Insulation Experts (??? Who ever they are???), and the homeowners themselves...!!! Too many times I see a window that just needs some TLC that has lasted up to 200 years in a home being replaced by one that simply won't last more that 15 (tops!!!) before more "consumerism" gets exercised to replace it...Great for the Industry that makes them...horrible for the environment and pretty unnecessary for the architecture that it downgrades and bastardizes!!!

There really needs to be more awareness and discussion of the short life of these double-paned windows. I think most people just aren’t aware that they have repeat this unholy expenditure for all their windows every 15 to 20 years. And multiply that by every house in the country then think about what it’s doing to the landfills. This is not sustainable!

Brent always comes with the knowledge to educate us 👍👍

Interesting! You always answer questions I didn't even know to ask.

It's called Pilkington Spacia. Thanks for introducing this. Very valuable information

A fantastic educational video. Thank you again for sharing your expertise. God bless 🙏

Curtains are great insulation! I love your 100 year window. Straight ¼ inch glass will last for ever. Thanks Brent!!

Thanks for the info. I'd love to see a video of an old window rehabbed with this glass.

idk why this was recommended to me but I enjoyed it thoroughly. thanks :)

Coming from UK, strange to consider 100 year old window as old! Great video

So cool to learn this stuff.

Single pane plate glass is the best. No heavy border, it's thinner, No double reflection when looking at the glass from outside, plus no tempering distortion. I don't mind that my house is a little bit colder for 2 months out of the year. I'm changing all my glass back to single pane. Those black buttons are so stupid, I thought you were joking at first. Good video anyway.

I hav been thinking of this for many years.

Your “mutton bar” is a muntin bar. Great window info!

For giggles, I'd do exterior face 1/8" borosilicate glass cold laminated to a 3/16" polycarbonate core cold laminated to an inner face of 1/8" borosilicate - for impact strength and temperature gradient shock hardening. Exterior glass face having a sputter deposited UV/IR mirror with full visible light bandpass, so it's protected from damage and dirt by the lamination. Polycarbonate provides web strength in tension should the glass break, the cold lamination would retain the bulk of the glass shards should the faces break, and would add some sound deadening to the stackup. Then do the mutton bars with a titanium extrusion welded into a grid and then to the window frame (structural titanium has about the thermal conductivity of vinyl, or slightly better). This would be so you can do the mutton bar in a traditional narrow width, but retain continuous pressure and vacuum strength - plus flexural strength against impulses. Individual lites held in with a Sika polyurethane structural adhesive for transferring that glass lite strength to the muttons and the frame. Maybe an anti-spall film on the inside bonded to the mutton, with a magnetic interior trim to allow for servicing the bond and enabling replacing panes (and painting the interior face of the mutton without having it on the glass?). Those little spacer balls look like ceramic vacuum spheres - I'll bet a custom lab glass shop could replicate those panes with a better plug for the vacuum (the same way they did vacuum tubes). That tube tail for the vacuum draw could be done on the face of the inner piece with the tail embedded in the cold lamination pour along the edge and therefore protected. I could also see a variation on this video's method which uses laser welding of the glass (Coherent does this with CO2 lasers). By gently rolling those little ceramic (I'd use Zirconia for teh low thermal conductivity) vacuum beads on the top face of one piece and lasing the glass from the oposite side the glass would melt at that location and a ceramic ball would "sink" into the melt and bond in place - makes for easier patterning of the spacers (the unwelded balls just roll off the surface). Then putting those balls in contact with a roller that applied a non-outgassing glass adhesive, would stick the two sides together when mated. By grinding a bit of the surface of each piece of glass around the rim of the pane, when the two pieces are put together a small void will be left. Right at the edge of that void one can do a glass weld. A small pre-made laser cut hole through one side of the glass to allow a vacum tube to be welded on (again laser) - to pull the vacuum. Then a laser welds a ring around the tube entry at the flat glass and the tube is laser cut a little proud of the glass surface, then melted down into the tube hole like a rosette weld for a permanent seal. Once the vacumm is pulled and the pane sealed, the void gets filled with the cold-laminating compound - which adds some mechanical stability to the joint (glass is directly sealed on itself, but no vibration or flexure would then crack the seal) "Pretty", thermally performant, acoustically deadened, storm impact rated... very, very expensive ;-)

I will be selling these windows to all my friends at the first summer BBQ. As always, great content!

I hadn’t even heard of spacia glass before this. At the moment, it is very expensive at a minimum of £200 per square metre - with that cost rising substantially (according to installers) if you wanted small-sized panes. I guess that, like most things, that price will fall over time, particularly when any (?) patent expires. I think that, as others have said, that you would need to live with one window of spaces to understand if the dots and the black dotes really annoyed you; perhaps a neoprene dot in clear might be better? I don’t know if it would be possible to make these vacuum panels using historic glass - i.e. slightly wavy - as it might not be possible to sled around the imperfect edges. A true divided light window is a joy to look at, just as is a “Tudor” window. For me, they just look right when windows with internal dividers (between the panes of a traditional double glazed unit) just look…..wrong. Glass in windows has obviously been around for a long time; the Roman buildings here in the UK (54 - 400 AD) were the first in the UK to have them and were obviously reserved the the most wealthy. Churches from Saxon times onwards had stained (or painted) glass windows but, for the common working man, it was the norm to have openings in the wall shielded by leather which could be rolled up if needed. I would dread to think what the R value of those were. Stained glass or “Tudor” style (lots of small panes joined by lead cames) are inherently weak structurally because the lead is itself not a good structural material. Now, you can buy saddle bars which is lead came with a steel bar in the middle of the lead; you can’t bend that but it would be fine for diamond or square panels within an overall large window. A great many historical buildings over here have had to install the surface steel or copper or brass reinforcing bars going from one edge to another with the leaded window braized to it.

That's pretty amazing but the dot would bug me (ha, sorry), and I really want wavy historical glass. I wish there was a way to get high r value wavy historical glass. But I'm all for the 100 year window concept, and I'd be building a house with crazy-high r value walls, anyway, so I think it'd be worth it to go with historical glass. I also want to do leaded windows, like what you'd see in a Tudor revival, do you have any special insights about those?

I'm working on my plans for an ICF Home and I love everything you do. Do you have plans to get into the impact resistant market?

Glad to see an alternative to insulated glass with space bars. I have seen so much of it fail, whether it was the seal or the lo-E coating. I have replaced lots of I-G units that where only a few years old, the glass was still intact but was full of condensation. Can Pilkington glass be retrofit into an old wood sash?

How well would the vacuum glass hold up in a door? I'm only getting 5 to 6 years out of insulated glass in doors.

So much worry about glass R values seems silly. If you have good storms the R value is way higher than all the expensive, fancy glass. I have steel casement (they go out) windows from 1927 and built interior storms with lexan and you don't even notice them. Cost me less than $2k for 40 windows.

Curious about the effects of solar pumping on the seals. 100 years is a long time to resist the pressure deferential cause by temperature changes. I would assume that this system has gone through some kind of cycle testing in order to verify whether it can withstand the years of temperature changes.

Hi Brent, do you prefer any type of interior curtain/shutter to put behind historic wavy glass to make it look its best from the exterior looking in? I didn't realize that bad blinds can ruin the look a historic window when viewed from the street... white paper blinds for example make the whole window look modern and you can't see the glass's waviness as well. thanks!

Does the classicist still offer classical architecture certification? The website noted enrollment for 2016- i emailed for more information, just impatient and curious lol. I appreciate your enthusiasm for these arts.

The black dot is a deal breaker for me; I'm sticking with single pain glass.

Please post a link where the homeowner can purchase the Pilkington Spacia product.

Do you use any of the reproduction wavy glass?

Put a polarizing lens or lens cover on your camera you should be able to reduce the glare on you white board, viewers will be able to see with more clarity.

Hi Brent, after watching this video I have tried to get a quote for purchase of the Pilkington Spacia glass as well as VacuMax. These products seem to be unavailable to the homeowner replacing their own window glazing. Each product has only one vendor in the US and are restricted to dealing with contractors.

ACQ in Germany make and edge sealed Vaccum unit with out the fill nipple of the Pilkington Spacia. I can’t get people to buy the Pilkington

I have original windows but the streets aren't maintained properly. Truck hitting potholes and loud music those take a toll on our windows when rattling. Does that mean it will stand this out of our hands situation .?

Andersen windows used to have glass like that except no ball spacers. They even had the the plugged hole where they sucked out the air and must have filled it with some kind of gas to keep the 2 sides spaced apart. How is that so different from the Pilkington glass?

Do you think there could/will ever be double/triple glazing with vacuum insulation instead of a gas?

I have storm windows over my sashes, so do I care about my sash panes being all high tech? I thought windows aren’t where you’re losing heat anyway. My attic is insulated to r-60. I own a couple sweaters. Moths gotta eat too, right?

Is the new glass a better R value than the old style insulated glass?

Would the dot look better in the middle so it looks purposeful?

Cool option, but seems difficult and expensive to order

We are still in the major issue: can you cut it at your shop or needs to be ordered?

Could you show us one of the windows with the black neoprene button on it that has been installed?

Whoever ripped out the original glass of my 28 working mans Tudor, i hope stubbs their toe often! They put in horribly cheap vinyl double hung... Good news the house still breaths 🙄

I didn't understood why/how insulated glasses stop to insulate in 15 -20 years.... Vacuum seem interesting, but with so much a difference of pressure, what i heard is that the vacuum only wants to go away, not like the classical insulated ones that have similare pressure with outside......

We are in the fake lead on some thermos windows. Disgusting. I had to do it…

Double glazing ? Everybody with some energy sense has it , in Europe. Where I live (UK) councils provide it free of charge, as well as cavity wall insulation. A no-brainer.

Great videos. I have to say though the constant repetition of "Right?" and "OK?" is distracting.

Regarding energy "savings", as long as you can recoup the cost...but the very rich could care less, its a talking point only, bragging rights, some new thing to talk to your friends about how green you are. I've seen mansions with solar panels? You got it, another talking point. So an R value of one or two? The rich are not thinking of that!

I’m tired thin sight line double glazed units failure rate in under 5 years is frightening so wasteful

Your info on thermal units is inaccurate. Any thermal unit with a stainless steel, aluminum or sometimes foam type of spacer around the edges is a "sealed" unit. The "band" around the edge is filled with silica beads to absorb moisture within the sealed cavity. The panes of glass are sealed, but they're not just a dead air space, the air is removed by vacuum. That is a standard "insulated unit". Removing the air provides a better insulating factor than merely 2 panes sealed together, something that doesn't exist. The upgrade, low e argon, is when the dead air space is filled with an inert gas, which is an even better insulator than a space void of air. Low e is a coating in between the 2 panes that reflects more bad sun in the summer, prevents fading of carpets and furniture, but allows more good sun to enter in the colder months when the sun is lower in the sky. The black dot is ridiculous and won't sell. 😂😂