Hi oberon! I hope that you realize that part of my exasperation at this point was that Guardian showed us what was possible, and now we are just trying to achieve that goal. But on to your questions... Guardian was the supplier to Benor well before we entered the process. When we went looking for windows and found Benor, and when our architect realized that the Guardian Architectural Division was willing to participate (there are some personal relationships involved here that made this happen), we started to get a tremendous amount of involvement by a couple of their engineers. The Guardian folks were very helpful in explaining to me and my wife ALL the sources which would degrade both the VT and CRI, and then discussed all that they could do to reduce their impacts. One of the larger impacts on VT that could be mitigated was the interlayer index of refraction mismatch by supercritical choice of the laminate interlayer (including the batch number). They spent hours showing us more than two dozen samples, taught me the laser trick, and then explained why we would want to use their ultra-white glass with Saflex rather than some of the other PVB products available, and why the PET interlayer while it delivered better impact performance was not the right one for us. That decision alone they explained would improve our VT dramatically. They then introduced us to the Munsen Color chart as a way to assess color neutrality, and a myriad of other details that would appeal to the artist in my wife. As we went through this process, they kept plugging the various lite selections into a program ("Windows 5.2") that predicted the performance of the whole glass assembly. Here is where I received the real education. What appeared to be relatively small changes in the components of the glass assembly (such as using the the ultra-white glass with Saflex) were responsible for increasing the VT by 5% (which I have come to find out is HUGE!) The spacer that they suggested was a specialty, "two polymer, warm-edge" system that separated a dual pane glass system. The gap was was about 0.267" and filled with krypton. No window glass on our house was wider than 32" (based on the advice of Guardian engineers). After Guardian designed the complete glass assembly, Benor used that data to estimate "whole window" performance (including frames) and based on these data Benor suggested that they use a "fully foam insulated" vinyl sash and frame for our windows. After this good experience, I had been very disappointed speaking with nearly all of the "established" window brands. Since then however, we have found a couple of specialty window makers that appear to be willing to work with us. The glass samples that they have sent us for inspection appear to be quite good and I am hoping that we end up with a positive outcome. If anything, I think I am the product of "raised expectations" that were the result of a specialty window manufacturer who had tremendous pride in his work and a glass supplier who (for whatever reason) decided to show us the "bleeding edge" "art of the possible" for our house.

What is the code for your area? What about your homeowners insurance? They might give you bigger discounts if your windows are approved, mine did. Also, your other big openings like double front doors, garage and sliders factor into insurance costs. I would think it is easier to specify for impact doors and windows during the build as opposed to retrofitting later. So these windows might be fine but without the designation, your insurance might not give you all the benefits you deserve. Just so you know, PGT windows is right off 75 near Venice. so it's in your area Their windows are MIami/Dade impact approved.

DO NOT BUY PGT WINDOWS! SIX YEARS AGO WE BOUGHT OVER $47,000.00 WINDOWS AND SLIDERS (7 SLIDERS) - as of yesterday I just filed / called for replacement of our fourth sliding glass panel doors - these are the Miami Dade double insulated with all the extras - failing. The seals do not hold. The company we bought the window/sliders from does not like going thru all the trouble to replace and then reinstall....they can charge me whatever price they want for labor. PGT will replaced the windows - they will probably say "out of warranty" - it is very unclear just exaclty what their warranty is (!). Do NOT do business with PGT....I am at the point of just replacing every defective window with a different brand .....this is so unfair and unprofessional and poor business standards....

Disagree with above comments. Impact windows add a lot of value to homes in SW florida for resale purposes. But you want to make sure you replace all of them -- not just some -- so that buyers can be assured that they will get the insurance discount. We were in a house in coral gables in the italian historic village (near CG high -- i'm assuming near your house), and without impact windows, our hurricane insurance was $17,000 a year. It went down to $10,000 with all impact windows. This is a question that EVERYONE asks about when you go to sell your house. Impact windows and date of roof. It's HUGE for resale purposes. I'd also argue that houses in historic areas in Coral gables and the grove are actually considered more aesthetically pleasing *with* the impact windows. It's considered a marker of a house that has been fully renovated. This is different than, say, washington DC (where i also lived) where aluminum new windows from the 90s are considered the sign of a cheaply done flip 20 years ago. Conversely, the thick border that is a give away of impact windows in florida is a sign of a good renovation. I have never heard of anyone in SW florida being particularly concerned with maintaining the historic elements of the old houses. They like the appearance of the old houses, but want the updates of new houses. This is also different than DC, where people tried to maintain the old features.