Double glazing guides
Written from published New Zealand sources, with every figure attributed and a visible date. Where we could not find a source, we say so rather than filling the gap.
Retrofit vs replacement windows in New Zealand
Retrofit costs $450–800 per m² of glass, replacement $800–1,600 (CheckMyBuilder). What each one actually changes, what stays, and which houses suit which.
Updated 15 September 2026 · 8 min readRead the guideH1 and your windows: what the 6th edition changed
H1/AS1 6th edition was published on 27 November 2025 and removed the Schedule Method. The 5th edition can be used until 26 November 2026. What that means for windows.
Updated 15 September 2026 · 6 min readRead the guideDoes double glazing need a building consent in New Zealand?
Usually not. Schedule 1 Exemption 8 covers window work in an existing dwelling of up to two storeys, with conditions. Here are the conditions, in homeowner terms.
Updated 15 September 2026 · 6 min readRead the guideWill double glazing fix condensation on bedroom windows?
Double glazing cuts condensation, but it does not remove the moisture. What glazing changes, what only ventilation changes, and what to do about a wet bedroom window.
Updated 15 September 2026 · 7 min readRead the guideWhat double glazing costs in New Zealand is the full cost reference, and the calculator prices your own windows against it.