Solar control​

Optitherm achieves a Solar Heat Gain Coefficient (SHGC) of under 0.60. Compared with 0.71 of a regular clear IGU, despite being just as clear

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Thermal insulation

Optitherm lets in the winter sun and works to reflect escaping heat back in the room during the colder months.

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High visibility

Optitherm boasts a Visible Light Transmission (VLT) figure of 78%, not too shy of regular clear glass plus the added performance benefits.

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Energy saving

The ability to ínsulate and light up a building results in far lower energy bills.


Glass Options

  • Available on Clear or Grey glass
  • Maximum sheet sizes – 4500 x 3200mm

Glazing options​

  • Double glazed in an Insulated Glass Unit (IGU) on surface 2 or 3
  • Can be paired up with LoE-i89 on surface 1 or 4 for unprecedented performance
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  • Buildings seeking natural light
  • Residential builds
  • Predominently colder climates
  • Southern facing windows
  • Price sensitive projects


A few example glass make-ups shown below. Please contact Glassworks if you require data for a specific make-up that is not represented here.

Light TransmissionReflectanceSolar Heat GainU-Value
Regular Low-E IGU
4mm Clear
12mm Argon
4mm clear
Optitherm® IGU
4mm Clear
12mm Argon
6mm Optiherm

Centre of glass calculated using LBNL Window 7.3 based on NFRC 100 environmental conditions

Get in touch

We are located at

8a Kitchen Road
Dandenong South VIC 3175

Call us on

+ 61 3 8788 5888

or email us

[email protected]

Please note that Glassworks is a glass manufacturer and not a glazier or window supplier. We supply the glass to the industry only.