Climate zone
Zone 1
Far North, Auckland, Coromandel and coastal Bay of Plenty
Whangārei · Auckland · Tauranga · Whakatāne
Free NZ postcode tool · H1/AS1 Sixth Edition
Find your H1 climate zone by postcode.
Get a fast postcode estimate, confirm the council that Appendix C uses, then carry the right zone into the H1/AS1 Calculation Method.
- Climate zones
- 6
- Source
- Appendix C
Standards checked · Postcode results are estimates; the H1/AS1 territorial-authority table is authoritative.
H1 climate zone postcode lookup
Start with the postcode. Finish with the council.
NZ Post delivery areas and H1 climate-zone boundaries are different geographies. The postcode narrows the answer; your territorial authority confirms it.
Source of truth: H1/AS1 Sixth Edition, Table C.1.1.2.
New Zealand H1 zones 1–6
Popular H1 climate zone answers.
These summaries make the national pattern easy to scan. Boundaries still follow the territorial-authority rows in Appendix C, including special splits in Rangitikei and Waitaki districts.
Climate zone
Zone 2
Waikato, Gisborne, Hawke's Bay, Taranaki and Whanganui
Hamilton · Gisborne · Napier · New Plymouth
Climate zone
Zone 3
Lower North Island, Wellington, Nelson, Marlborough and Chatham Islands
Palmerston North · Wellington · Nelson · Blenheim
Climate zone
Zone 4
Central North Island, Wairarapa and the South Island West Coast
Rotorua · Taupō · Masterton · Greymouth
Climate zone
Zone 5
Canterbury and the eastern and coastal South Island
Christchurch · Timaru · Dunedin · Oamaru
Climate zone
Zone 6
Alpine Canterbury, Central Otago and Southland
Twizel · Queenstown · Alexandra · Invercargill
Read the result correctly
A climate zone feeds the heat-loss comparison.
Under the Sixth Edition Calculation Method, the selected zone changes parts of the reference building. It does not turn every number in the reference table into a standalone minimum for your proposed construction.
Reference-building coefficients
H1/AS1 Table 2.1.2.7 supplies values for roof plus skylight, opaque wall, slab-on-ground, other floors and the reference building's 30% wall glazing. Thermly applies them in the whole-building reference heat-loss equation.
Separate non-tradeable minimums
Section 2.1.2.11 sets construction R-value floors of R2.6 for roofs, R1.0 for walls and R1.3 for floors other than slabs. Slab-on-ground floors have no minimum in that clause. The Calculation Method also caps wall glazing at 40% of gross wall area.
Why council confirmation matters
Postcodes describe delivery areas. H1 zones follow council boundaries, with explicit geographic splits for two districts. Use the finder for speed, then record the territorial-authority basis in the consent evidence.
Climate zone FAQ
Common H1 climate zone questions.
- What H1 climate zone is my postcode in?
- Enter the four-digit postcode above for a quick estimate, then confirm the territorial authority. H1/AS1 defines the six climate zones by territorial-authority boundaries, not postal boundaries.
- How many H1 climate zones are there in New Zealand?
- H1/AS1 Sixth Edition has six climate zones. Zone 1 covers the warmest northern areas, while Zones 5 and 6 cover colder southern and alpine areas, but the official council table is the source of truth.
- Is a postcode enough to select an H1 climate zone?
- A postcode is useful for an estimate, but it is not authoritative. Postcode delivery areas can cross council or H1 boundaries. Appendix C says its territorial-authority table takes precedence over the climate-zone map.
- Are the reference R-values minimum insulation requirements?
- No. The Table 2.1.2.7 values are reference-building coefficients used in the Calculation Method heat-loss equation. H1/AS1 also sets separate non-tradeable construction R-value minimums for roofs, walls and floors other than slabs.
- Which H1 zones are Auckland, Wellington and Christchurch in?
- Auckland is Zone 1, Wellington City is Zone 3, and Christchurch City is Zone 5. Nearby councils can differ: Upper Hutt City, for example, is Zone 4.
From zone to calculation
Swap the old schedule mindset for the Calculation Method.
Carry the climate zone into Thermly, connect construction R-values to measured envelope areas, and compare proposed heat loss with the H1/AS1 reference building.
Primary standard
H1/AS1 Sixth Edition, Appendix C and Table 2.1.2.7. Open the MBIE PDF.
Check the postcode
If you need to confirm the postal address itself, use the NZ Post address and postcode finder.
This finder is explanatory support, not a substitute for the cited standard, amendments or project-specific professional judgement. Read the complete H1 compliance guide for the Calculation Method workflow and transition dates.