Vinyl R5 windows
sethery05
| Posted in Energy Efficiency and Durability on
Does anyone have experience or knowledge of the Vinyl Kraft – TrustGard triple pane vinyl windows? On the surface it seems like an incredible value. R5 + Triple pane for a very low cost. (about $19/sf ). The air leakage is average compared to other vinyl windows.
Thank you for any insights.
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I was just about to add a window question to my own remodel thread, but given two have been asked this morning it makes sense to piggy-back.
Is that price for fixed glass or operable?
I got a price on Intus windows, which claim to be R8 and the fixed glass is $30/sq ft and the operable is coming in at $72/sq ft for a 24"w x 36"h tilt'n'swing.
I also stopped by my local building supply store and they recommend Mathews Brothers which are manufactured in Maine, not sure how the price out yet.
The $19/sf was for an operable double hung. It was based off of a window size of 36"w x 62"h.
Seth. Just curious if this is for new construction or a renovation. Do you have a particular energy goal in mind? I ask because sometimes you want a high-quality window to ensure good performance over tiime. For example, Intus is a great product and a relative bargain compared to comparable German windows.
Is there a definitive answer on what the Intus Uw values are? As far as I can tell the R8/U0.01 ratings are for the glazing.
The best U number I can find for an Intus window in the NFRC database is 0.18 which is much closer to the R5 value Seth is quoting for these Vinyl Kraft window.
Seth - based on the same database the U0.18 Vinyl Kraft windows have SHGC values around 0.15 and VT of 0.28-0.31. By comparison the U0.18 Intus option have SHGC of 0.3 and VT of 0.46...
These are for new construction windows. My energy goal is basically achieving the best I can with a very modest budget. I'm in Climate Zone 5A (Chicago, IL). For my situation, the life cycle costs and time value of money to make a jump from an R5 window to an R8 window would not make sense for me.
I'm no expert on the numbers, but I think a VT rating of 0.3 means a pretty dark window, to the extent where it will actually look tinted, which might explain how they are getting the high R value for such a low price?
I looked at my Intus quote from about 2 years ago. I also remember looking up the U value on their web site and it claimed around U-.12 for the whole unit. This is from the quote. Note the VT is .709
System: EFORTE WINDOW
Fittings: Multi-Matic
Frame: INOUTIC passive house window profile
Color: White/White
Filler:
1: Prem4x20Arx4x18ArxPrem4, warm edge spacer, Ug=0.088 Btu/hr sq.ft F, SHGC=0.494, VT=0.709 (4)
Sash: 1: Tilt & turn
I paid about $45 per square foot for an operable 40x48" window.
Thanks Stephen. Ug is the value for the glazing though, but that VT value is amazing! I'm thinking on a north facing wall those windows would be great, solar gain isn't a concern and you're getting tons of light in... South facing wall might be a different story!
Ben- I haven't had a problem with too much solar gain from south windows. Frankly, here in Maine, any additional winter heat is welcome. I have a substantial overhang so summer sun is pretty shielded.
When comparing performance numbers for European windows, always keep in mind that the values are calculated differently in Europe than they are in North America.
IF the European window manufacturer is simply converting the metric U values derived from European calculations into North American U values then the numbers will look better than they would if the window had been tested to North American standards.
It isn't possible to do an apples to apples comparison between Euro calculations and North American calculations because of different test parameters, so when looking at European window performance numbers it's worth considering where those numbers come from.
Also, it isn't a stretch to see window manufacturers from both sides of the pond using glass-only performance values to promote their windows, but it does seem to be increasingly common for distributors of European windows in North America really pushing that "questionable" tactic as they try to hit the growing passive and net zero market.
The debate about performance value comparisons between European and North American manufacturers was very active on GBA a couple years ago. Anyone new to the site and/or interested in window performance might find it interesting and maybe even informative.
I got my quote for Intus windows from PBS in Portland, ME and they shared with me the calculation they use to calculate a Uw value from the Uf, Ug and other data points, including window dimensions, frame size etc...
Even if the calculations are favorable for the purposes for marketing, I think $ for $ the Intus windows are hard to beat.