Whole window SHGC is lower than glass-only SHGC, and is generally below 0.8. Solar heat gain can provide free heat in the winter but can also lead to overheating in the summer. How to best balance solar heat gain with an appropriate SHGC depends upon the climate, orientation, shading conditions and other factors.
Eakle, A.S. (1929), Probertite, a new borate, American Mineralogist: 14: 427-430. Schaller (1929) USGS Professional Paper 158: 137. Foshag (1931) American Mineralogist: 16: 338. Barnes (1949) American Mineralogist: 34: 19, 611. Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II.
Polyethylene terephthalate (aka. PET, PETE, PETG) is a plastic resin of the polyester family that is used to make beverage, food and other liquid containers, as well as for some other thermoforming applications. PETG is a clear amorphous thermoplastic that can be injection molded or sheet extruded.It can be colored during processing.ETG can be semi-rigid to rigid, depending on its thickness, and it is very lightweight. The main virtue of PETG is that it is fully recyclable. Unlike other plastics, its polymer chains can be recovered for additional useIt makes a good gas and fair moisture barrier, as well as a good barrier to alcohol and solvents.