You May be Surprised by the Number of Glass Options for Your Custom Windows, and It is Important to Understand Which Would be Best Suited for Your Requirements. Standard Glass is Called ‘Low E’ and is a Great all Round Option for Energy Efficiency. Low Iron Glass Offers High Clarity and Energy Efficiency. Toughened Glass is Five Times Stronger than Regular Glass and Laminated Glass, Contains a Plastic Interlayer Offering Better Insulation and Resistance Against Damage