Selecting the right glass for your home.
Glass plays a critical role in your home's appearance, comfort, and energy efficiency. The right glazing can help reduce heat loss, minimize noise, block UV rays, and improve year-round comfort. With single, double, and triple glazing options, along with coatings and insulating technologies, choosing the right glass can significantly impact your home's thermal performance and security, as multi-pane glass is far more resistant to breakage than a single pane.
Understanding glazing options
Single glazing: A single pane of glass provides minimal insulation, allowing significant heat loss in winter and heat gain in summer. It is rarely used in modern homes due to its poor energy efficiency.
Double Glazing: Consists of two panes of glass with an air or gas-filled gap in between, acting as an insulating barrier. This reduces heat transfer, helping keep homes warmer in winter and cooler in summer. Adding a Low-E coating, which is highly recommended, reflects heat back inside, further improving thermal performance. Please see below for why we recommend it.
Triple Glazing: Features three panes of glass with two insulating air or gas-filled gaps for even greater insulation. Ideal for colder climates or high-noise areas, triple glazing provides maximum energy efficiency, noise reduction, and condensation control.
A single pane of glass offers minimal insulation because glass is a good conductor of heat. As a result, much of the warmth in your room literally goes out the window.
Double glazing traps a layer of air between two panes of glass, substantially reducing heat lose through the window because air is a poor conductor of heat. Adding a Low E coating to the inside of one of the panes of glass can further improve insulation because the coating reflects heat back into the room.
Triple glazing provides two insulating layers of air between three panes of glass, reducing heat loss even further as air is a poor conductor. This delivers enhanced thermal efficiency compared to single or double glazing.
Enhancing glass performance
Beyond glazing layers, there are additional technologies that can be added to the glazing units to improve thermal efficiency:
- Low-E coating – A transparent low emissivity coating that is added to the inside of one of the panes of glass that reflects heat back into the room
Sunlight is made up of three components. Low-E coatings affect each differently:
- Visible Light (VL) – Minimal impact
- Low-E coatings are designed to maintain high visible light transmission, meaning they allow plenty of natural daylight to enter the space
- Some Low-E coatings may appear to slightly tint the glass – witnessed as a slight blue or green hue
- Infrared (IR) Radiation (Solar Heat) – Reduces heat gain and loss
- Low-E coatings reflect infrared heat while allowing natural light to pass through
- In hot climates, they reduce heat gain by reflecting solar infrared energy outside
- In cold climates, they retain indoor heat by reflecting infrared energy back inside, reducing heat loss
- Ultraviolet (UV) Radiation – Blocks harmful rays
- Low-E coatings can block up to 99% of UV radiation, which helps prevent fading of furniture, carpets, and artwork
- This protection reduces long-term damage caused by prolonged sun exposure inside the home
There are a range of Low-E products designed to impact these three components to varying degrees. Speak to your local consultant before selecting your glass.
- Argon gas fill – Replacing the air between the panes of glass with Argon gas further reduces heat loss
- Thermal spacers – These separate the panes of glass and are designed to minimize the amount of heat escaping through the edges of the glass unit
- Tinted or Laminated glass – Helps with solar control, UV reduction, and or noise insulation
Benefits of double or triple glazing
Why choose Double or Triple glazing?
- Better insulation – Retains warmth in winter and keeps heat out in summer.
- Lower energy bills – Reduces the need for heating and cooling.
- Less condensation – Helps prevent moisture buildup on windows.
- Improved noise reduction – Ideal for homes in busy or high-traffic areas.
- Enhanced security – Multiple panes offer increased resistance to break-ins.
- Compliance with the New Zealand Building Code – Low-E double glazing is now typically required in new builds.
For most homes in New Zealand, double glazing offers a significant improvement in warmth and efficiency. However, in colder regions or noise-prone areas, triple glazing may provide additional benefits.
Your local Nulook® consultant can help you select the right glass, and create a more comfortable, energy-efficient home that meets your needs both now and in the future.
