Question:
What is the thermal rating for laminated glass compared with double glazing? Is double glazing safety glass the same as laminated glass.? Thank you.
-Dave H.
Papakura, New Zealand
Answer:
Dave,
Thank you for contacting the Glass Detective with your question regarding what you refer to as “glass thermal ratings”. The quick response is as follows: ¼” (6mm) laminated glass has an approximate winter nighttime U-Value of 1.02 while a 1” (25mm) insulating glass unit made with clear glass and with no coatings of any kind has an approximate winter nighttime U-Value 0f .47. Laminated glass is a safety glass product and can be used in insulating (double glazing) assemblies. Tempered glass would also qualify as a safety glass in single or double glazed assemblies. It is suggested that you contact and work with a trusted glass shop in your area for additional information and assistance in choosing the right glass product for your project.
-Glass Detective
I live in south FL. I want replacement impact Windows. I hate the green color of LowE glass. My big windows face north. My electric bill is only 150 per month. I’m fine if I don’t get a reduction in my electric bill by switching to clear SGP laminated glass, but one salesman told me that that switch would actually raise my electric bill by increasing my heat gain. I think he is wrong. Is he?
Thank you,
David.
David, based on the information you have provided, a change from a green tint to a clear glass may have an impact on your heat gain situation. However, there are neutral (meaning almost clear) low-e glass products that can be incorporated into your new glass compositions that will offset most if not all of any heat gain concerns.