Triangular Window

Dave Pascoe · Post by **Dave Pascoe** » Fri Feb 20, 2004 1:30 pm

Hi everyone.

I was approached about doing a job months ago, and finally it looks like it`s happening.

I have to make two windows that sit in the east and west end of a building. To be more accurate, I`m making two panels that will be inserted in between the two sheets of glass in a double glazed unit.

The windows are triangular in shape and measure approx 180cm x 80cm. Sort of long thin triangles.

I`ve worked out the designs that I want, colours etc. I will be working in bullseye glass, all transparent.

The windows will have a sunset and sunrise in the appropriate end of the building. The client hasn`t decided on the final design yet, but it will more than likley be a clear base with either frit or solid ( or both) colour built up to create a sunrise/set. The colours are the most important thing I think.

Does anyone have any experience of this type of work?

My main concerns are with actually fitting the glass into the unit. I guess that you would have to use some kind of spacers to keep the glass in place.
As the panel will be sealed inside the unit, the strength of my panel shouldn`t have to meet any saftey regs.

Also, if there is anyone in the uk that would like to give me a ballpark figure for this type of job, then please send me a private message. I have already put in an estimate, but I`m curious to see what other people think.

This job will probably lead to more work with this developer, so I`m looking to make a really good impression.

Thanks in advance to you all!!!!

Dave...

Dani · Post by **Dani** » Fri Feb 20, 2004 3:59 pm

Be really cautious with your annealing schedule with any large pieces that will get sunlight and heat build-up... which might be more of an issue with sandwiching in an insulated unit. Stress fractures happen and they're no fun to replace. In fact, they're really expensive for the artist.

Becky Bergsma · Post by **Becky Bergsma** » Fri Feb 20, 2004 4:17 pm

You can seal your glass yourself using Super Spacer and sealant available from CRLaurence Co.

http://www.crlaurence.com

Becky

Dave Pascoe · Post by **Dave Pascoe** » Fri Feb 20, 2004 5:34 pm

Thanks for the replys so soon.

Dani, I`ve thought alot about how to install the windows. Putting them inside the units seems like the easiest option. It`s a new build and the window units are being custom made. I can get my panels put in when they manufacture the units. Do you have any other suggestions?

Saftey regs become an issue if my panel is the outer piece of glass. And I don`t think the client would go for a hanging panel in front of the window.

What is the range of tempetures within the double glazed unit?

Proper annealing would give protection against any stress though, right?

Do you ever insert glass pieces into a window unit?

Thanks again, Dave

Dani · Post by **Dani** » Fri Feb 20, 2004 8:46 pm

We never do... with conventional leaded stained glass, we have a problem with heat build-up and lead degradation... at least in this environment which is mountain desert. Even exterior glazing that isn't vented creates problems with the art glass. I don't know exact temperatures on the glass, but we have had smaller fused inclusions fracture long after installation. They were clearly stress fractures on well-annealed pieces and not large pieces. I still don't have a real comfort level with fused glass that's exposed to extended periods of sun. Even the festival artists on this site have commented on fracturing when bowls are left in the sun too long. Maybe I'm just paranoid. Or just know my environment well enough not to hazard the risk. That said, I know that artists on the coasts routinely sandwich leaded glass (uncemented) and that procedure protects the lead from salt deterioration. You may benefit from that scenario more than I. All things to consider.... and I wasn't much help, was I?

Gale aka artistefem · Fri Feb 20, 2004 11:26 pm

Dave.......a friend of mine did this in his house, where he had complete architectural and builder control decision making powers. His house is a huge labor of love that he hand-built stick by stick and stone by stone.

He put heat vents (drilled slots) in the wooden framework holding the glass panes. This allows the heat to dissapate, rather than build up between the panes. His sandwiched glass is stained glass-lead fabrication, though. No fused glass included.

The other thing he did was install the glass in a way that he could remove the glass panes for cleaning. When you leave a breather opening in the framework, you eventually get dust build-up and moisture streaking and the glass needs be cleaned. It's a trade-off.

Hope this helps.

Dave Pascoe · Post by **Dave Pascoe** » Sat Feb 21, 2004 8:18 am

Dani, at a guess, I would say that the environment you live in is probably quite a bit more extreme than where I am. We get some good sun in the summer but for a lot of the year the sun is pretty weak.

Saying that though, I could do with some sun right now!!!!!!!!!

The other thing that I realised is that because the windows are in the east and west ends of the building, they will miss the heat of the midday sun. The sun will rise in the east and then bathe the south facing wall all day, and then set in the west. So I would have thought that if the windows were in the south wall they would get a lot more sun/heat build up.

Lots to think about........

Dayle Ann · Post by **Dayle Ann** » Sat Feb 21, 2004 9:32 pm

Dave, east and west facing windows may actually get more direct sun and heat build-up than south facing windows, especially during summer months when the sun rises in the NE and sets in the NW at northern latitudes. The sun is moving in a parabolic arch, so that it is shining at closer to a 90 degree angle to the windows through most of the morning or afternoon.

Though the thickness of the atmosphere when the sun is low in the sky may moderate the effect, there can be a lot of heat buildup inside the window layers. Solar designers generally advise against using east and west windows for heat gain for this reason: you are getting the most heat buildup at exactly the season you least need it (I know several homes where this is a problem. The heat occurs after the sun's rays pass through the glass, and has little to do with the outside temp.

Special coatings on the window glass to screen out uv might help keep this from happening.

Dayle Ann

Dave Pascoe · Post by **Dave Pascoe** » Sun Feb 22, 2004 9:39 am

Ok, I went back to the site and had a good look around. The east side of the building is shaded by large trees, which will obviously shade the east end from spring onwards. Both ends of the building are shaded by an overhanging roof, which will also provide shade from some sunlight.

I`m going to give the client the option of a panel in float glass, with the sunrise/set in texture on one side. If I used a single piece of float, this would get around the problem of stress fractures wouldn`t it? I don`t know if they will be interested, but I`m going to offer this as the cheap option to the client....

So many things to think about!!!!!!!!!

Dave Pascoe · Post by **Dave Pascoe** » Sun Feb 22, 2004 9:42 am

Dayle, what coatings would you recommend? Would this be a plastic self adhesive film?

I guess that you`d apply this to the inside of the outer piece of glass?

Dayle Ann · Post by **Dayle Ann** » Sun Feb 22, 2004 3:49 pm

Since the windows are being custom built, you should be able to work with your client to have them made with coated glass. Discuss the needs with the firm building the windows-- they should be aware of which coatings will serve your needs best.

I am pretty new at fused glass, and have been interested in the concerns that people have about stress from overheating in windows. Most of the stories seem to be about slumped and curved pieces. I wonder if the stress in those cases is induced by differential heating-- the part closest to the window heating more. I suspect that a flat panel might not be as subject to that kind of stress. The uv coating may reduce the heating enough that it may not be an issue at all for you. Perhaps the window makers can provide some insight.

That said, I think if I were doing this project though, I'd go for an interior installation that worked with the design of the exterior windows. (I'd be paranoid). I can visualize a couple of things that could work (rods that fasten the corners of the piece but allow air to circulate, for instance).

Dayle Ann

Dani · Post by **Dani** » Sun Feb 22, 2004 5:14 pm

The pieces we use in church windows have been flat and mostly self-fused.... in other words, two pieces of the same glass fused together. Several of those have fractured particularly in one window and one church. Somewhat similarly to stress fractures we've experienced in large pieces of glass that had second pieces glued with UV glue, then installed in a west facing window.... in my climate, that's like facing inferno! I agree with you that even a seeming small amount of sun can cause damage in insulated units.... sort of a magnet held in the sun effect almost. Curious to observe, no fun to repair especially if you're just being a good businessman and doing it for nothing. After all, I essentially sold a product with some flaws, right? That didn't manifest until after-the-fact. Life is an adventure.

Other times, a pain in the glass.

Vic · Post by **Vic** » Sun Feb 22, 2004 6:44 pm

How about install an IG unit that has a "low E" coating and filled with argon gas. This unit should keep much of the heat outside. Now, laminate your fused glass to a piece of 1/4" tempered glass (should meet code). Install fused unit in front of IG, with a 1/2" air space. Have venting slots at the top and the bottom of the interior installation. this will allow any heat and moisture to escape.

Vic · Post by **Vic** » Sun Feb 22, 2004 6:48 pm

Should have added that the lamination glue needs to be flexible to allow for different COE of the plate glass and the fused glass.

Dave Pascoe · Post by **Dave Pascoe** » Sun Feb 22, 2004 9:26 pm

Well, after much thought, and some good advice from Dani and Dayle, I`ve decided to mount the panel internally.

I kind of got stuck on my original idea to mount the panel inside the window unit. It now seems to make sense to mount the panel in a frame, probably stainless steel. I`ll get the double glazed unit made with UV coated glass. I`m also going to apply a saftey/UV protective film to the back of my panel.

I can then mount the frame to the inside of the window frame, or into the wall. I won`t mount the frame flush to the window unit, to allow air to move around it and keep the heat down.

This also means that if anything ever did go wrong, or they need to access the window, then my piece can be taken down easily.

Thanks guys,you made me think about this in more depth than I had been.

Dave Pascoe · Post by **Dave Pascoe** » Sun Feb 22, 2004 9:30 pm

Hi vic,

You posted while I was replying.

Your idea is pretty much what I`m now planning to do.

I need to see the architects tomorrow, but I`m pretty sure that the window is above 800mm from the floor, which means no saftey regs apply to this window. All the same, I`ll feel better if it has a film backing for saftey and UV protection.

I have been a bit worried about this job, but I feel much more confident now the panel is outside the sealed unit.

Thanks for your idea though......

Dani · Post by **Dani** » Mon Feb 23, 2004 1:25 am

And you know what, Dave? You did your homework and the client is going to be impressed by that. I hope this turns into a great BIG job for you. Also, don't forget to send some pictures for the gallery after you've installed. I'd love to see them. I'm going to send some of the one church that we are now in the process of completing. Will be some different fused applications to show, this larger architecutural stuff.

Dave Pascoe · Post by **Dave Pascoe** » Mon Feb 23, 2004 6:09 am

thanks for your help Dani. It`s going to be a couple of months till the panels are in, but the build has to be finished for the summer season. I`ll definatly post some pictures when they`re finished.

It would be really good to see some of your work. There isn`t a lot of architectural work on the site really, it will be nice to see some more.

I`m also waiting for my new kiln to come for this job. 2.4m x 1.2m internal dimensions. I`m really excited about this. It will be so good to be able to do some BIG work, architectural and studio stuff. I`ve had the urge for ages to make a massive bowl, 1m diameter...!!!!!!! What fun!!!

Anyway, see you soon..........

charlie · Post by **charlie** » Mon Feb 23, 2004 11:48 am

Dave Pascoe wrote:Dayle, what coatings would you recommend? Would this be a plastic self adhesive film?

I guess that you`d apply this to the inside of the outer piece of glass?

these are low-e coatings, not available outside of the glass manufacturers. whoever is building the window has to put it on, and there is a summer and winter gain glass (which side of the glass it goes on is different), so it's latitude dependant.

ask whoever is providing the float to the window fab shop to do this. plain float won't work as well as coated flat.

Dave Pascoe · Post by **Dave Pascoe** » Mon Feb 23, 2004 8:11 pm

I had a chat to the architects today, and the windows are coated -low e, and argon filed. We`ve decided to have the window frames adapted, just a recess on the inside of the frame which will allow me to slot my panel right in and then put some beading in to secure it. The frames will be drilled in such a way that the air will be able to move between my panel and the window unit.

So, it seems to be coming together now......