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1. Can you use low-e glass by Vitro Architectural Glass (formerly PPG glass) in a single-glazed window?
2. Is it better to have the coating on the #2 or #3 surface of an insulating glass unit?
3. What are the differences between low-e coated glass products by Vitro Glass?
4. Do all low-e coated glasses look the same?
5. How much does low-e glass by Vitro Glass reduce the transmission of ultraviolet (UV) energy?
6. Can tinted glass be used with low-e glass?
7. How effective is tinted glass with low-e coatings by Vitro Glass?

7 Total Questions

1. Can you use low-e glass by Vitro Architectural Glass (formerly PPG glass) in a single-glazed window?

Sungate® 400 coated glass and Solarban® 60, Solarban® 67, Solarban® 70XL, Solarban® 72, Solarban® Z50, and Solarban® R100 coated glasses must be used only as a component of a sealed insulating glass unit.

In addition, all low-e coated glasses yield their best energy performing characteristics when used in sealed, insulating glass units.

2. Is it better to have the coating on the #2 or #3 surface of an insulating glass unit?

The answer to this question is really dependent on the specific design conditions of your application. The light transmittance and the U-value of the unit will be the same whether the coating is on the #2 or #3 surface. However, the Solar Heat Gain Coefficient will be lower when the coating is on the #2 surface.

In general, if you are concerned about reducing solar heat gain (typically in a cooling climate), then using the coating on the #2 surface would best meet the requirement. On the other hand, if you are interested in utilizing passive solar heat gain (typically in a heating climate), then using the coating on the #3 surface would best meet the requirement.

3. What are the differences between low-e coated glass products by Vitro Glass?

Vitro Architectural Glass (formerly PPG glass) manufactures a variety of low-e coated glasses using two different manufacturing processes. The following table identifies the Vitro glass product and associated manufacturing process.

PPG Low-E Coated Glass Products
Product Manufacturing Process
Sungate® 400 Coated Glass MSVD
Solarban® Z50 Coated Glass MSVD
Solarban® 60 Coated Glass MSVD
Solarban® 67 Coated Glass MSVD
Solarban® 70XL Coated Glass MSVD
Solarban® 72 Coated Glass MSVD
Solarban® R100 Coated Glass MSVD

In the pyrolytic manufacturing process, the coating is applied to the glass ribbon while it is being produced on the float line and the coating then “fuses” to the hot glass surface. The glass is then cut into stock sheets of various sizes for shipment to fabricators. For pyrolytic coatings, Sungate® 500 and 600 coatings are very durable, both mechanically and chemically. And, while Sungate® 500 and 600 coated glasses offer reduced emissivity and some solar control, they do not perform quite as well as Magnetic Sputtering Vapor Deposition (MSVD) by Vitro Glass.

In the MSVD process, the coating is applied to pre-cut glass (usually in stock sheets for further fabrication) in a vacuum chamber at ambient plant temperatures. MSVD coatings such as Sungate® 400 and Solarban® 60 low-e glasses offer lower emissivity and superior solar control versus pyrolytic. However, MSVD coatings are not as durable as pyrolytic coatings, either mechanically or chemically, and must always be used as a component of an insulating glass unit with the coating located within the sealed airspace.

4. Do all low-e coated glasses look the same?

No, they do not. Color differences between various low-e coatings are due to the use of different coating materials and the thickness of the various coating layers, as well as differences in manufacturing processes.

5. How much does low-e glass by Vitro Glass reduce the transmission of ultraviolet (UV) energy?

The reduction in the transmittance of UV energy is dependent on the specific low-e coating by Vitro Glass and the make up of the insulating glass unit, i.e., glass thickness, glass type, etc. Please refer to the product performance charts for specific information.

6. Can tinted glass be used with low-e glass?

Yes it can. Tinted glass can be used as the outdoor lite in an insulating glass unit, with low-e glass by Vitro Glass as the indoor lite. The low-e coated glass improves the insulating properties of the insulating glass unit, while the tinted glass reduces the influx of solar energy through the insulating unit.

7. How effective is tinted glass with low-e coatings by Vitro Glass?

  • Tinted glass is very effective when used in conjunction with low-e glass by Vitro Glass. This combination will reduce excess heat gain and lower cooling costs.
  • The tinted glass reduces the amount of excess heat gained on the east, west and south exposures
  • Tinted glass can provide improved glare control, if needed.