Your home should be a place of comfort, not cold drafts and rattling windows. If your windows are single glazed, much of your warmth and peace slips straight outside. Renovating with double glazing brings lasting comfort, quiet and energy savings.
At NK Windows, we help Kiwis modernise their homes with high performance glazing systems built for New Zealand’s climate.
Windows Drive Heat Loss
Glazing surfaces are often the weak link in a home’s thermal envelope. BRANZ research cited in Build Magazine shows that windows and doors can account for 40% heat loss in your home, especially in poorly insulated homes. (Build Magazine – Double Glazing: It’s Worth It) BRANZ Build
BuildingNZ’s guidance also states that by double glazing a window you can halve the heat loss through that glazing compared to a single glazed window of the same size. (Building.govt.nz, Glazing and Glass Options) Building Performance
Due to this, improving window performance yields large gains in comfort and energy savings.
What Double Glazing Does — The Mechanics
Double glazing uses two panes of glass separated by an air or inert gas gap. This arrangement slows heat transfer by conduction, convection and radiation. (Level NZ – Glazing Options for Temperature Control) level.org.nz
In addition, using low emissivity (Low E) glass coatings and argon gas between the panes can boost thermal resistance further. Some sources note a 5 to 20 percent gain, and much higher with Low E glass, up to 90 percent better, in insulation compared to air fill. (Level NZ) level.org.nz
Real Benefits You’ll Experience
A Warmer, More Stable Home
The first thing most homeowners notice after upgrading is the change in comfort. With less heat escaping through the glass, rooms hold warmth longer and stay at a more even temperature.
“The impact of the new double-glazing is immediately visible in the change in temperature volatility. Before the installation, both sensors showed wide daily swings, with average max–min differences of around 6–8 °C per day, and an overall spread of readings spanning more than 10 °C. The standard deviation during this period was also elevated, reflecting frequent sharp rises and falls. After the windows and doors were installed at the end of July, those swings narrowed dramatically: the average daily range dropped to roughly 2–3 °C, and the overall spread compressed to less than 5 °C. It confirms that the double glazing substantially reduced temperature volatility in the home, providing a more stable and comfortable indoor climate.” — Nikki & Phil Brown
Less Condensation, Healthier Air
Condensation can cause dampness and mould that affect both your home and your health. Because double glazing keeps the inner pane closer to room temperature, moisture has fewer cold surfaces to cling to. The result is cleaner air, fewer allergens and a noticeably drier, healthier living environment.
(Build Magazine – The Pitfalls of Avoiding Double Glazing)
A Quieter, More Peaceful Space
Many homeowners say noise reduction is one of the most immediate improvements they notice. The dual panes and sealed air gap act as a sound buffer, softening traffic, neighbours, and wind.
BRANZ notes that high-performance glazing significantly improves acoustic comfort, especially when paired with thicker or laminated glass.
(Build Magazine – Double Glazing: It’s Worth It)
Protect What’s Inside
Natural light is essential, but harsh sunlight and UV rays can fade furnishings over time. Modern Low-E coatings on double glazing block much of this ultraviolet and infrared light while keeping rooms bright and inviting.
EECA and Level NZ both highlight that these coatings reduce solar heat gain and protect carpets, curtains, and furniture from fading.(EECA – Energy Efficient Windows and Doors)(Level NZ – Glazing Options for Temperature Control)
Secure, Efficient and Built to Last
Beyond comfort and appearance, double glazing also strengthens your home. Thicker or laminated glass, reinforced frames and modern locking systems increase security while enhancing energy efficiency, a combination NZ that buyers increasingly look for.
