How long does a building consent take in New Zealand?
The 20-day rule, why it rarely means 20 days, and how long a new home really takes from first sketch to consent in hand.
Updated 1 October 2026 · By CAD Consultants Ltd
By law, councils have 20 working days to decide a building consent application. The clock stops whenever council asks for more information (an RFI) and restarts when you answer. For a typical new home, allow about 13 to 19 weeks from first sketches to consent issued: roughly 9–13 weeks of design and documentation, then 4–6 weeks with council including RFIs.
What the 20 working days actually mean
- Working days exclude weekends, public holidays, and the period from 20 December to 10 January.
- The clock starts when council accepts your application as complete, not when you submit it.
- The clock pauses while an RFI is open. A week waiting on an answer adds a week to your timeline.
Typical timeline for a new home
| Stage | Typical time |
|---|---|
| Free consultation | Week 0 |
| Concept design | 2–3 weeks |
| Developed design | 3–4 weeks |
| Consent documentation | 4–6 weeks |
| Council processing, including RFIs | 4–6 weeks |
| Total to consent issued | 13–19 weeks |
Larger homes (over about 260 m²), multi-unit projects, and sites with slopes, flood overlays, heritage rules or existing buildings take longer. A resource consent, if needed, adds its own timeframe.
What slows a consent down
- RFIs. Missing bracing calculations, unclear junction details, or a specification that doesn't match the drawings.
- Engineering that arrives late, or doesn't match the architectural drawings.
- Site issues found late: TC3 land, flood overlays, covenants or service easements.
- Slow answers. Every day an RFI sits open is a day added.
How to speed it up
- Check land category, hazard maps, title and covenants before design starts.
- Brief the engineer early so structure and drawings are coordinated.
- Lodge a complete set: bracing to NZS 3604, H1 energy calculations, details, schedules, specification and the LBP Certificate of Design Work.
- Answer RFIs within days, not weeks.
Canterbury and Otago councils
We've taken 391 projects through 23 councils, most often Selwyn (122), Christchurch (113), Queenstown Lakes (43), Waimakariri (31) and Central Otago (28). The 20-working-day rule is the same everywhere; what differs is each council's typical RFIs and local hazards. Selwyn District Council recognised CAD Consultants as an Approved Building Partner for 2026.
Common questions
How long does a PIM take?
Councils also have 20 working days to issue a Project Information Memorandum (PIM). For a consent-exempt granny flat, the PIM is the main council step before building starts.
Can I start building before my consent is issued?
No. Building work that needs a consent can't start until the consent is granted. Starting early can lead to fines and a Certificate of Acceptance process that costs more and takes longer.
Does a granny flat need a building consent?
Not if it meets every condition of the granny flat exemption: up to 70 m², single storey, detached, simple design, at least 2 m from boundaries and other dwellings, and built by Licensed Building Practitioners. You still need a PIM and must notify council on completion.
What is an RFI?
A Request for Information is council asking for more detail or a correction before it can decide your consent. While an RFI is open, the 20-working-day clock is paused.