You could spend good money on high-performance double-glazed windows and still end up with cold frames, condensation, and higher heating bills — just from getting the installation wrong.
It sounds surprising, but the majority of thermally broken and high-performance windows installed in New Zealand are put in the wrong way. It’s not a tradesperson issue — it’s a building code default that hasn’t caught up with where window technology has gone.
What’s the issue?
Modern high-performance windows have a warm barrier through the middle — in uPVC frames, the entire frame is thermally non-conductive. But for that to work properly, the frame needs to connect to the insulation layer in your wall.
When windows are face-fixed to the outside of the wall (hung over the cladding, as is common in NZ), that thermal connection is broken. The edge of the window is exposed to cold outside air, creating a thermal bridge — a pathway for heat to escape in winter and for condensation to form on frames.
The correct approach is to install the window recessed into the wall, so the insulated frame lines up with the insulation in the wall cavity. This is standard practice in Europe, where high-performance joinery has been the norm for decades.
Why does it matter?
Installing your windows correctly — recessed rather than face-fixed — gives you:
- Less heat loss around the window perimeter, meaning lower heating bills
- No condensation on frames, even in cold weather
- No mould risk in window reveal areas
- A noticeably warmer feeling near windows in winter
The performance data backs this up. A uPVC window installed recessed to the centre of the wall achieves an fRSI value (a measure of condensation risk) of 0.64 — rated World-Class. The same window installed the standard New Zealand way rates lower and drops to Poor in some configurations. The difference is significant when you’re paying for good joinery.
Is it more expensive?
Barely, if at all. The material cost difference between a correct recessed installation and a standard face-fixed installation is minimal. The bigger cost is getting it wrong — you pay for good windows and don’t get the performance you’re owed.
How Livara installs your windows
At Livara, we install Ambiance uPVC windows using a purpose-designed installation method that ensures your frames are correctly positioned within the wall. You get the full thermal benefit of the uPVC frame, not just the benefit of the glass.
If you’re replacing old joinery or building in South Taranaki and want windows that perform as intended, get in touch for a free quote.