Some of the more commonly specified formats used in First windows and doors are detailed here. Glass choice is often a balancing act between responding in the best way to sound, light, heat and UV control. 

Double-glazing offers good sound dampening qualities but more important are its thermal advantages. In summer double-glazing reduces heat and UV entry. In winter it provides good light and reduces outward heat loss. 

Safety glass
All First Windows & Doors products are supplied with glass that complies with NZS 4223, the glazing standard cited as an acceptable solution in the New Zealand Building Code.

The decision in glass selection is usually one of balance between light, heat and fading control from UV. The greater the light transmission, the less heat and fading are controlled.

Clear Glass & Low E Glass

4mm clear / 12mm air gap / 4mm low e

Low E (or low emissivity) glass enhances the insulation value of the double-glazed unit. Consider using with an Argon gas fill in order to gain maximum effectiveness.

G Clear Glass And Low E Glass