Difference in U-values/SHGC/Visible Light major or minor?
Let's assume you have 2 windows that are identical in many aspects except for the following values:
My questions, and they can be answered more generally rather than specifically addressing the above examples (which are just for illustrative purposes) is as follows:
-Is a U=.15 considered to be 50% better than U=.30? Is a price increase of 50% justified if that's the case?
-Is the difference between a SHGC=.25 and SHGC=.30 able to be felt by the average homeowner, or is it negligible?
-Is the difference between Visible Light=.4 and .5 able to be detected by the human eye on average, or is it again negligible?
I guess I'm trying to see if you are splitting hairs once you get within .05 or so of these numbers, because if yes, then comparing windows would end up being more on warranty/reputation/installation/quality instead of the NFRC labels, right?