Triple Pane Windows in a Landmark Area
I was thinking that the argument of double pane versus triple pane windows was pretty basic, but it’s not that easy. On the surface, it would seem that triple is better. Apparently that is not necessarily so. Each type of window has strengths and weaknesses. Any experience in a landmark building with triple pane? Brand…
I was thinking that the argument of double pane versus triple pane windows was pretty basic, but it’s not that easy. On the surface, it would seem that triple is better. Apparently that is not necessarily so. Each type of window has strengths and weaknesses. Any experience in a landmark building with triple pane? Brand recommended? Exact type? Prices? Anybody has really installed a triple pane window and can tell the difference? On top of that, we are in a landmark area in Brooklyn, it’s a brownstone. Any help will be very appreciated. We are trying to avoid a very expensive mistake. Thank you!
call Tom Byrnes at builders distributor 800 564 4206
approvedwindowsales.com
Agree with comments above and would add the following:
When comparing U-Value (the lower the better), make sure the manufacturer is giving you whole assembly U-Value.
They tend to like to give glass U-Value only because it is always lower than the frame’s U-Value.
Once you know the U-values of both assemblies, you can actually calculate the savings of one window over the other like this:
Take U-Value of the double pane and subtract the U value of the triple.
This is U-Improved.
Now, do this simple calc:
U-Improved * Area of Windows being Replaced * 4910(Heating Degree Days in NYC – another conversation) * 24 hours a day
= Total BTU Improvement of Triple Pane Window over double Pane. (X for short)
Assuming you’re using natural gas to heat, divide X by 100,000 and this is +/- annual Therms USED for heating.
Divide therms by 0.80 to account for boiler inefficiency (if you have a high efficiency boiler, divide by .9 or .94) and you have the Therms you are actually PAYING for, every year estimated.
Compare this to your current energy rate, and you know your estimated annual heating savings by going to the better window…
Compare that to the price increase for the triple panes and you get a sense for whether it is (economically) worthwhile…
FYI: For a true savings potential, you’d also need to calculate coolings savings…do you AC?
The area of glass as a percentage of the surface area of exterior wall is quite low (as compared with a window walled highrise). Therefore whatever you do will result in a relatively small increase in overall efficiency given the cost involved and the headaches dealing with landmarks. You’d be better off spending that money on more/better insulation, higher efficiency furnace, or even photovoltaic panels for the roof which are heavily subsidized (my neighbors in CG got theirs approved by landmarks).
The only thing that would make me hesitent about triple windows is now you have yet another space between the glass where condensation can form, should the seal break.
This is the one drawback of double and triple paned windows, that damn seal breaks, then you are fukked and have to get new glass installed…..
Trust me, I have done this procedure for the 2nd time already.