I just pulled out my old folder containing all the Bills and lists pertaining to building the greenhouse, installing the heating system and electrical wiring.
Now looking at Florian's Bill, it states that we used glass panels with a heat repellent rating of 4.7. I seem to remember something like a 17 % UV reduction. If one looks closely, the glass panels have a very faint grayish tint.
Kathy, is this the info you are looking for?