Glass options

Standard Homerit PVC-U windows and doors are double glazed.

Thickness of glass unit:

Casement windows and doors: 4mm to 29mm

Standard sliding windows: 4mm to 20mm

Large frame sliding windows: 4mm to 24mm

Standard sliding doors and stack doors: 4mm to 24mm

Heavy duty sliding doors: 4mm to 29mm

Safety glass:

NZS4223 is the glass safety standard in New Zealand. Safety glass is toughened or laminated glass which is safer than standard glass when it is broken.

NZS4223 requires safety glass in certain areas such as bathrooms, stairwells, schools and for certain designs for example full height glass or hinged doors.

Obscured glass:

Obscured glass is usually used in bathrooms for privacy protection. The three most popular obscured glass types are following:




These obscured glass types are popular and low cost options. There are severl other obscured glass types such as white laminated glass, opalucent laminated glass and etchlite glass which are often used for entry doors. These types are more expensive.

Tinted glass:

Tinted glass reduces the amount of UV, visible light and heat that pass through the glass. Popular choices are grey tinted, green tinted and blue tinted. Compared with standard glass tinted glass is slightly more expensive.

Laminated glass:

Laminated glass is safety glass. Laminated glass can also reduce UV and sound passing through the glass. Laminated glass can eliminate over 90% of UV light making it the best option for UV protection. Double glazing with laminated glass can reduce sound by over 50% so it is also a good choice for noise reduction.

Sound Reduction Rating

Low E glass:

Low E (Low Emissivity) glass keeps in heat while allowing light to enter your home. This can further improve heat insulation of your double glazed windows and doors.

Low E glass has a special coating on it. Although  transparency of Low E glass has improved with technology, Low E glass still looks slightly blue tinted. There are different types of Low E options.

Argon/Krypton gassed:

Standard double glazing units have dry air inside the glass. Double glazing units can instead be filled with argon or krypton gas to improve thermal insulation.

R-values of Homerit PVC-U Windows

Glazing Type R-value (M²K/W)
Classic double glazing, Air R0.41
Low E1/Clear double glazing, Argon R0.50
Low E2/Clear double glazing, Argon R0.58
Low E3/Clear double glazing, Argon R0.67
Low E4/Clear double glazing, Argon R0.74
Low E4/Clear double glazing, Krypton R0.82
Low E4/Low E4/Clear triple glazing, Argon R1.00
  • R-values are from BRANZ Appraisal No. 543[2022]
  • R-value of double glazed aluminium windows is R0.26
  • R-value of double glazed thermally broken aluminium windows is R0.32

Colonial bars: 

Colonial bars can be put between the two glass panes of a double glazing unit, so there is no need for cleaning. Aluminium colonial bars may reduce thermal insulation of double glazing.

Double glazing with colonial bars

Cat flaps:

Cat flaps can be fitted into double glazing units. If you need a cat flap, please request one when placing your order with us. It will cost more to add a cat flap later because the double glazing unit will need to be replaced.

Aeromat ventilator:

Window ventilation systems bring fresh air into domestic and commercial properties. Ventilation units fitted into windows combine efficient technology with a pleasing appearance.

Double glazing with Aeromat on the top

Ventilation is adjustable by turning the buttons at both ends of the unit. Aeromat not only provides controlled air flow but also keeps insects out.

Homerit services …

Specifier resource
Send us building plans or details of windows and doors for a
Free Quote