Financing your joinery upgrade

Financing your joinery upgrade

Money3 min read3 chaptersJan 2026By The Lume Team

There's a sensible way to fund warmer windows. Here are the reduced-rate bank loans that cover double glazing, why the spend pays you back, and how to phase the work over time.

01

Bank energy loans

Several New Zealand banks now offer reduced-rate or interest-free loans for energy-efficient home improvements, and double glazing qualifies. Here are the main programmes worth asking about. Each sits below a standard personal-loan rate and is written to cover work like window upgrades, and your own bank likely offers something similar.

  • ANZ
    ANZGood Energy Home Loan

    A home-loan top-up for energy-efficient improvements, at a reduced fixed rate against your existing lending.

    • Reduced rate for energy upgrades
    • Added to your existing home loan
    • Covers windows and doors
    Visit ANZ (opens in a new tab)
  • W
    WestpacGreater Choices Home Loan

    Up to $50,000 interest-free over five years for a warmer, drier, more efficient home, double glazing included.

    • Interest-free up to $50k over 5 years
    • Double glazing is eligible
    • For Choices home-loan customers
    Visit Westpac (opens in a new tab)
  • BNZ
    BNZBetter Future home loan top-up

    A home-loan top-up at a low fixed rate for eligible energy-efficient upgrades to your home.

    • Low fixed rate for 3 years
    • Covers efficient home upgrades
    • Borrowed against your equity
    Visit BNZ (opens in a new tab)
  • Your own bankGreen & energy loans

    Most major New Zealand banks now offer a reduced-rate or interest-free loan for energy-efficient home upgrades. Talk to your bank's representative to find out what's available for your window project.

When you talk to your bank, mention you're upgrading to double-glazed or thermally broken aluminium windows; most of these programmes are written to cover exactly that. Rates and terms change, so confirm the current offer directly with the bank.

02

Your investment

Quality windows are one of the smarter things to spend on at home, because the gain keeps coming back. Low-E double glazing in thermally broken frames can cut heat loss through the window by up to 73%* against single glazing in a standard frame, and a quality aluminium window is built to perform for 25 years or more. The upfront cost is offset by lower power bills and a warmer, drier, quieter home for decades.

Estimated heat-loss reduction through the window compared with single-glazed, standard (non-thermally-broken) aluminium framing. Actual performance depends on window size, glass configuration, install quality and your home's conditions, and does not represent total household energy savings.

03

Staging the work

Not ready to do the whole house at once? We can prioritise the rooms you live in, living spaces and bedrooms first, and phase the rest over time, so you feel the benefit where it matters most without committing to everything upfront.

Not sure what your home needs?
Book a free site measure, we'll spec it room by room.
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