Double vs triple paned on this window quote
nfiorito
| Posted in Energy Efficiency and Durability on
Hi all!
I’m wondering if the performance of an identical window moving from double to triple paned will make up for the price difference in the long term (I suspect it will).
Our quote from one company for all windows (Vinyl, Energy Star Rated) is $21k for our new build.
The upcharge to move from double to triple for all windows and doors (fixed and operating) is $1700+tax. Canadian pricing and Zone 7 build.
Would you do it? It seems reasonable to me. I’ll attach the quote with window list here in pdf form (hopefully this is kosher).
Thanks in advance for your insight!
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Unfortunately the file is too big to attach even after deleting some pages.
upload the file to https://www.scribd.com/ or email it to me mhaskell at gmail and I will upload it
Hi Nik,
May I ask who is the manufacturer as I need some windows for my reno in BC.
Nik,
The 8% upcharge is probably worth it for comfort reasons alone.
If you want to figure out the payback period for the energy savings, the calculation becomes more complicated. That calculation would require energy modeling for both options; once you know the annual energy savings, you can perform a payback calculation. For more information on payback calculations, see Payback Calculations for Energy-Efficiency Improvements.
One option to consider is to specify triple glazing for the east, west, and north windows, and to specify high-solar-gain double glazing for the south windows. Since double glazing usually has a higher SHGC than triple glazing, this approach may make sense.
That's a pretty small upcharge. Are the triple-pane units three pieces of glass, or two with a piece of film in between?
You should get the specs, I.e. SHGC and U values, as well visible light transmission,(VT) which should help you decide.
I would look at the SPECS for the double vs triple pane. Simply shoving three panes of glass into a window frame doesn't make for an energy efficient triple pane window. There is one window company that does just that. They cram three panes of glass into a tight space leaving very little to no space between the panes. This hurts R-Value. One could fit all three of their panes into the spacing of a typical dual pane window. They also then use a cheap spacer and their vinyl frame extrusions are a joke, very flimsy.
Take a look at a high-quality PVC window like Intus Windows. The quality is very apparent.
It's possible to build pretty good U0.25 double pane windows, and it's possible to build low-performance U0.35 triple pane windows. The specifications need to be more than the number of layers or an Energy Star label.
That said, Natural Resources Canada maintains a specifications list for all or most Energy Star windows sold in Canada:
http://oee.nrcan.gc.ca/pml-lmp/index.cfm?action=app.search-recherche&appliance=WINDOWS
Dana, that's a very useful list. Thanks.