Historic HomeWorks Forum

[chevychase]

Hi,
I've reproduced set of sashes for one window opening to replace a window from 1990ties. This window is completely off and doesn't match original ones from 1920ties with beautiful wavy glass in it.
Now, I have a dilemma what glass should I use. The window faces south and it is a library room so I am concern about sun exposure.
The max glass thickness that I can insert is 1/4 inches, but minimum 3/16. I can’t use thinner glass since the muntins are too wide so I am afraid that glazing will be too shallow (the woodmaker did wood stops to attach the glass but I prefer to use a putty).
Max thickness doesn't allow to use an insulated double pane.

My options are:
1. salvaged old wavy glass but max thickness is 1/8- too thin for me
2. new glass with 1/4 inch thickness - no wavy glass. Here, I can get also low iron glass, but I don't know if it is good or not. Unfortunately no low-e option for a single pane
3. historic reproduction from http://www.restorationwindowglass.com/. I can get wavy glass, 1/4 inch thickness, low-e – perfect but the price is astronomical - almost $2000 for 30 sq ft
4. reproduction from other source - Artisan Glass Works - 1/4 inch available, competitive price, but the glass quality is not impressive
5. Have anyone had experience with a Specia from Pilington http://www.pilkington.com/en/us/products/product-categories/thermal-insulation/pilkington-spacia#overview? I've just requested a quote. The glass is double pane but around 1/4 inch thick and low e. No wavy glass.

Should I just get a salvaged old glass but thin or go with new regular glass no low-e but thick?

If I use low-e, have you experienced any difficulties in glazing? Do I need a special patty or Sarco is sufficient.
Thanks so much for your input.

[SashGuy]

Tempered glass picks up a slight wave in the heat treating process, so I use it quite often when large pieces of cylinder glass are not available. Chose your thickness.
My choice in film is Iris 75. It reflects radiant energy outward, rather than heating the glass (unlike OTC products), and is completely clear so that the wave in the glass is not distorted.

[chevychase]

Thanks! So new tempered rather than annealed glass. Do you know where I can buy the Iris 75 film? It doesn't show on google.
I assume that the film must be on exterior side of the window. Do I glaze first and then put the film or vice versa?

[SashGuy]

Sorry, that is Iris 70 http://geoshieldusa.com/architectural

[chevychase]

Thanks.
Do you put the film on the glass first and then putty?

[SashGuy]

Film is always installed on the interior