Double glazing for your home, priced window by window.
Enter your window sizes and see a sourced price range for each one. One measure turns it into a fixed quote. Our partner glazier makes and fits the glass; your contract is with us.
What we do, and who does the fitting
Three sentences, because this is the thing every other site leaves vague.
We price and we measure
Every rate on this site is published by someone else and shows its source and the date we checked it. The measure is ours, and it is what turns a range into a fixed number.
A partner glazier makes and fits the glass
A contracted retrofit glazier makes the sealed units and fits them into your existing frames, or replaces the window. We name them before they come.
One contract, and it is with us
From estimate to handover you deal with NZ Double Glazing. You are not signing with a subcontractor and you are not chasing three quotes.
Three ways to double glaze
Published New Zealand rates, checked 15 Sept 2026. Which one suits you depends on your frames, and the measure settles that.
Timber window retrofit
Sealed units into your existing timber sashes. The joinery, the profiles and the character stay.
$800–1200 per windowWellington GlassRead moreAluminium window retrofit
The cheapest honest route to double glazing in a 1970s–90s house, without new joinery.
$550–850 per windowWellington GlassRead moreFull window replacement
New joinery and new glass, when the frames have had it or you want a thermally broken frame.
$1,500–$2,500+ per openingWellington GlassRead moreNot sure which?
Price your windows both ways in a couple of minutes, then we'll say which we'd recommend at the measure.
FreeRead morePrice your windows
Not a room count and not a size bucket: your own measurements, one row per window, with the rate and its source printed on every row.
- Retrofit at $450–800 per m² of glass, or replacement at $800–$1,600 (CheckMyBuilder).
- Published per-window floors applied, so a small window is not priced as if it were cheap.
- Low-E, thermally broken joinery and scaffolding shown as separate, sourced lines.
- A total range rounded to $100, with what is not included listed underneath.
Estimate, not a quote
The calculator shows a low–high range. It never shows a single number, because nobody can give you one without measuring your windows.
A typical New Zealand retrofit job is around $16,000, with most between $10,000 and $25,000 (CheckMyBuilder).
Four steps, one contract
And you pay most of it only once the glass is in.
- 1
Price your windows online
Free, a few minutes, no email needed.
- 2
Book a measure
$149, credited in full to your job.
- 3
Get a fixed written quote
Within 5 working days of the measure, valid 30 days.
- 4
Glass in, then the balance
A 25% deposit orders your units; the rest when the job is done.
What's true today
No reviews, no job counts and no memberships here, because we don't have any yet. These we can stand behind.
- Every price shows its sourceAnd the date we last checked it. If a rate moves, the site moves.
- Usually no consent neededRetrofit in a home of up to two storeys is generally exempt (Building Act Schedule 1, Exemption 8).
- A written contract on every jobWith the MBIE disclosure statement and checklist, not only on jobs over $30,000.
- No glazing grant existsWarmer Kiwi Homes funds ceiling and underfloor insulation and heat pumps, not glazing (EECA). We say so.
Common questions
How much does double glazing cost in NZ?
Retrofit into your existing frames runs $450–800 per m² of glass and full replacement $800–1,600 (CheckMyBuilder, checked 15 Sep 2026). Per window, Wellington Glass publishes $550–850 for an aluminium retrofit and $800–1,200 for timber. A typical whole-house job is around $16,000. Price your own windows.
Can my existing frames be double glazed?
Usually, if the joinery is sound and deep enough to take a thicker sealed unit. Timber sashes and most aluminium joinery retrofit well; rotten or corroded frames do not. That is the first thing the measure checks, before you commit to anything.
Do I need a building consent?
Usually not. Schedule 1 Exemption 8 of the Building Act covers window work in an existing dwelling of up to two storeys, provided the window being replaced hasn't failed its 15-year durability requirement. Exempt work must still comply with the Building Code. The conditions in full.
Will it stop condensation?
It reduces it, often a lot, because the inside pane is much warmer. It doesn't remove the moisture: ventilation does that. EECA lists reduced condensation and mould among the benefits of insulating windows. What glazing changes, and what it doesn't.
Who does the work?
We price, measure and manage. A retrofit glazier we contract in your area makes the sealed units and fits them. You have one contract, with us, and we name the glazier before they come.
When do I pay?
$149 for the measure and the fixed written quote, credited in full to a job signed within 60 days. Then a 25% deposit when you accept the quote, which pays for your units to be made, and the balance when the job is finished.
Guides
All guidesRetrofit 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.
Read 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.
Read 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.
Read the guideKnow roughly how many windows? That's enough to start.
You don't need exact measurements and you don't need to decide between retrofit and replacement. Put your windows in and we'll show you both.
Price my windowsNZ Double Glazing is a trading name of Kauri Ridge Holdings Limited, NZBN 9429050000017. All prices in New Zealand dollars, including GST.