Okay, so the vinyl company we may use sources it's glass from the same company as Pella - is this good or bad!??! I can get triple pane, or any of the other low e treatments. So, would you (WoW or eastbay or WindowsMike or ?) recommend double pane, low e 180 on south windows and then triple pane on all others? (what is the low e rating on triple pane windows - or do you choose that too?) Or maybe just triple pane on north wall (faces a lake)? Or....??? (We are doing full ICF for exterior walls, if that makes a difference?) Triple pane on ALL windows seems a bit excessive and pricey??! We also have some really big windows, so I don't know about the weight of them (does that affect efficiency)? I have been trying to find the U and SHGC numbers for the vinyls that we are looking at...haven't found them yet. Thanks for your time, patience and help!

Hi ZIns, Oberon offered professional technical details so I will chime in with homeowner experience. Yes, even with Low-E, there will be fading. Depending on the amount and intensity of exposure and the finish, it is a matter of how much and how soon. In a situation where the sun is very mild and light, by the time fading is noticeable, it may also be time to refinish the floor. My guess is the floor is not receiving year-round exposure, true? The sun is stronger and deeper during some time of the year and weaker and less intense at other times, is that so? We have seasonal sun intensity problem too and solve it with a combination of solution. We use rugs to protect several sections of our floor during mid-Spring through late Summer. The rugs are removed to prevent tripping when we have visitors. The rugs are also removed around Autumn when the sun is low and the exposure is much less intense and shortening each day. We have old furniture in one area by our French doors and my wife made knitted coverings to cover the furniture. As necessary, we remove the covering when appropriate. Outside the French doors, we installed retractable awning so that during extremely hot summer days, the awning extends to provide cover without blocking natural light. Our goal is to not use any window treatment because we enjoy natural light and the views. Hope this helps a bit.

Both LoE-366 and LoE-270 are Cardinal coatings. The visible transmittance of the 366 coating is 66%. The VT of the 270 is 70%. Neither the 366 or the 270 are tinted coatings. Although small samples might look a bit different, few people would notice a difference in the light entering a home when using the 366 versus the 270.

I would opt for the higher VLT if in your area. Michael