My thought as well, millworkman. Julie, I am going to assume that the coating is between the two lites of the laminated glass rather than as part of an IG unit. Two reasons, first since you are in the Keys, and as millworkman alluded to, you probably don't have an IG to start with. You are more than likely dealing with monolithic lami glass. Second, some dual silver LowE coatings, SB60 being one, tend to turn purple (at least it looks purple to me) when placed inside a laminated lite. Interestingly, the color is normally only visible from one side of the glass - depending on which lite in the laminate has the coating. The other side will look more or less normal often depending on lighting and viewing angle. As a rule, the refractivity of a LowE coating is going to be influenced by where and how the coating is being used. Basically a LowE coating designed to be clear when used in an IG airspace might react differently when used in a laminated lite - it may no longer be clear - it may be a bright and pretty color other than clear. Because this is not an unknown phenomenon to coating folks, some LowE providers have designed slightly different versions of their coatings depending on whether the coating will be inside an IG facing an airspace or being used inside a laminate, or they may simply not offer a particular coating inside laminated glass, or they may even reengineer the coating so that it can be used in either an airspace or in a laminate. While Solarban 70XL (triple silver) is an example of a coating that can be used in either application, as I recall, I cnn't remember if that is true of SB 60 or not. But, based on your description of the color, I am going to guess that the SB60 "version" in your laminated glass may fall under the "cannot-be-used-in-laminated-glass-or-it-will-display-as-a-color" category. Again I am just guessing, but your description definitely points in that direction. Since PGT manufactures both IG and mono-lami glass for their windows, it occurs to me that they MAY bring in two different variants of the SB 60 coating - one for IG and one for lami. If so, it may be possible that in the manufacturing process the folks who cut the glass for manufacture as either lami or as IG may have inadvertently used the wrong version in your laminated glass. Again I am only guessing, but since PGT is one of the very few window companies who also run a laminated glass line (I can only think of two other's off the top of my head), I would suspect that such a mix-up is certainly possible. Again again, since all this is predicated on the assumption that there really ARE two different versions of SB 60, my first question to PGT if I were you would be to ask if that is a possible scenario. If you call them directly and mention the color shift I very much suspect that their quality people will know exactly what you are talking about..

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.

SunCoat max (i.e. Cardinal Low-e 366) will cut down on the SHGC to the extent that it will certainly impact any passive solar heating ability of the sun. If you rely on passive solar, you need to re-examine your choices. Where is the home located? Read the article linked below.... Here is a link that might be useful: Zero Energy Article

Where is the home located? If it is covered and will not be exposed to direct radiant energy from the sun, the necessity of something in the 3-coat Low-e range (i.e. Cardinal Low-e 366) goes away. You still do want a Low-e to assist with heat flow in either direction, i.e. saving energy in the winter as well, but you can certainly go with a Low-e 2 range or even higher VT rated coating. https://www.cardinalcorp.com/technology/reference/loe-performance-stats/