Do the Healthy Homes standards require double glazing?
No. The Healthy Homes standards don't require double glazing in NZ rentals. They do set rules for openable windows, draughts and heating capacity, and glazing changes the heating number.
By the NZ Double Glazing team
Key takeaways
- The Healthy Homes standards do not require double glazing. None of the five standards (heating, insulation, ventilation, moisture and drainage, draught stopping) names a window type.
- Windows do matter under three of them: openable windows for ventilation, no unreasonable gaps for draught stopping, and the glazing you have feeds the heating capacity calculation.
- Ventilation: living room, dining room, kitchen and bedrooms need openable windows, doors or skylights of at least 5% of the room's floor area, able to stay fixed open (Tenancy Services).
- All rental homes have had to comply since 1 July 2025 (HUD). Landlords in breach can face penalties of up to $7,200 (Tenancy Services).
- Double glazing can lower the heating capacity the living room needs, and a home whose insulation and glazing all meet the 2009 standards can be assessed under the newer heating formula.
No. The Healthy Homes standards don't require double glazing in New Zealand rentals. They require openable windows in the main rooms, no unreasonable gaps that cause draughts, and enough heating to bring the living room to 18°C. The glazing you have is one of the inputs to that heating calculation, so double glazing can reduce the heater size the standard requires.
What do the Healthy Homes standards say about windows?
| Standard | What it asks of windows |
|---|---|
| Ventilation | Openable windows in the living room, dining room, kitchen and bedrooms; openable windows, doors and skylights at least 5% of each room's floor area; able to stay fixed open |
| Draught stopping | No unreasonable gaps or holes in windows, skylights, doors, walls, ceilings or floors that cause noticeable draughts |
| Heating | Window sizes and glazing type are inputs to the required heating capacity for the main living room |
| Insulation | Ceiling and underfloor only; windows are not part of it |
| Moisture and drainage | Not about windows |
Does double glazing help a rental meet the heating standard?
It can. The heating standard requires a fixed heater able to warm the main living room to 18°C, and the required capacity comes from the Heating Assessment Tool or the formula in Schedule 2 of the regulations. The tool asks you to measure every window in the living room's external walls, frame included, and to describe the glazing, because glass is one of the surfaces heat escapes through. Less heat lost through the windows means a smaller heating requirement.
There is a second effect. Since the 2022 amendment, rentals where all the insulation and glazing meets or exceeds the 2009 standards can use a newer formula with lower assumed heat losses, which generally produces a smaller required capacity (Tenancy Services). The 2.4kW line matters here: if the required capacity is above it, a plain electric heater no longer qualifies and you need a heat pump or another qualifying heater.
Does double glazing count as draught stopping?
Not by itself. The draught stopping standard is about gaps, not glass: sashes that don't close, missing putty, gaps around frames, broken panes. Tenancy Services sets no maximum gap size; its guidance helps you judge what is unreasonable. Retrofitting sealed units usually means new beads and seals and a sash that closes properly, which fixes the gaps as a side effect, but a well-sealed single-glazed window also complies.
Should a landlord double glaze anyway?
- For compliance, it's optional. Meet the five standards first; none of them needs double glazing.
- For the heating number, it can help if the living room's required capacity is just over what you have installed, especially near the 2.4kW line.
- For condensation and mould complaints, it's one of the better fixes, because a warmer inside pane condenses much less. Ventilation still comes first; see the condensation guide.
- Grants don't help here. EECA's Warmer Kiwi Homes excludes rentals, and it doesn't fund glazing for anyone (more on grants).
- Retrofit is the cheaper route on sound frames, at $450–800 per m² of glass against $800–1,600 for new windows (CheckMyBuilder). See retrofit double glazing.
Can a tenant ask for double glazing?
A tenant can ask, but the standards don't oblige the landlord to install it. What a tenant can require is that the home meets the standards: openable windows that stay open, no unreasonable draughts, and heating of the required capacity. If those aren't met, Tenancy Services explains the steps, and landlords in breach can face penalties of up to $7,200.
Questions
Is double glazing a Healthy Homes requirement?
No. None of the five Healthy Homes standards requires double glazing. Windows come in through ventilation (openable windows of at least 5% of the floor area in the main rooms), draught stopping (no unreasonable gaps) and the heating capacity calculation.
Does double glazing reduce the heating I need under Healthy Homes?
It can. Glazing is an input to the Heating Assessment Tool, and homes where all the insulation and glazing meet the 2009 standards can use a newer formula that generally gives a lower required capacity (Tenancy Services).
When did rentals have to comply?
All rental homes have had to comply with the Healthy Homes standards since 1 July 2025 (HUD). Before that date there were staged deadlines tied to new and renewed tenancies; those have now passed.
Is there a grant for double glazing a rental?
No. EECA's Warmer Kiwi Homes is for owner-occupied homes and doesn't fund glazing. See our grants guide for what else exists.
Do I need consent to double glaze a rental?
Usually not. Window work in an existing house of up to two storeys is generally covered by Schedule 1 Exemption 8 of the Building Act. See our consent guide.
Sources
Published 19 October 2026, last updated 19 October 2026 by the NZ Double Glazing team.