Source
https://www.branz.co.nz/pubs/bulletins/bu704/ — original source (opens in a new tab; the file is not redistributed)
BRANZ Bulletin 704 — Small dwellings exempt from consents
Read this as a CONSTRAINT, not an enabler
BU704 was queued on the expectation that the ≤70 m² consent exemption would open a consent-free pathway for a community of small dwellings. It does close to the opposite. The resource-consent exemption (NES-DMRU) is a granny-flat rule — one minor unit ancillary to a principal dwelling, same site, common ownership — and it lapses precisely where there is on-site wastewater disposal, i.e. the off-grid case. And the building-consent exemption forecloses both earth-wall construction and wood heat. What survives is a real ~$4,000/dwelling consent saving. See Neobiome Intelligence relevance.
Summary
BRANZ Bulletin 704 (March 2026, 6 pp) explains the new Building Act Schedule 1A exemption — a new, stand-alone, single-storey dwelling up to 70 m² may be built without a building consent — and the parallel Resource Management (National Environmental Standards for Detached Minor Residential Units) Regulations 2025 (NES-DMRU), which allow a minor dwelling up to 70 m² without a resource consent in residential, rural, mixed-use and Māori purpose zones. Both came into effect in January 2026.
The two exemptions are separate instruments on separate axes (Building Act vs RMA) with different scopes, and BU704 is careful to say so. That distinction is the whole story for Neobiome: the building-consent exemption may be usable at community scale, while the resource-consent exemption almost certainly is not. BU704 also sets out the Schedule 1A conditions in detail, and two of them exclude technologies central to this project.
Key claims
- claim: "Schedule 1A exemption: a new, stand-alone, single-storey dwelling up to 70 m2 needs NO building consent, provided design/construction meet the conditions, the work is carried out or supervised by licensed building practitioners (LBPs), a project information memorandum (PIM) is obtained from the council BEFORE work starts, and specified documents (incl. records of work) are provided on completion. 70 m2 is measured between finished internal faces of external walls; an attached or internal garage may be included. Classified 'Housing - detached dwelling' (Building Code A1); must comply with the FULL Building Code regardless of the exemption."
source_location: "1.0.1, 2.0.2, 1.0.4"
- claim: "In force January 2026. Estimated saving of consent costs 'over $4,000' for an average exempt dwelling. Council DEVELOPMENT CONTRIBUTIONS may still apply and are notified through the PIM process; the PIM itself is a compliance cost."
source_location: "1.0.6"
- claim: "MATERIAL LIMITS: the exempt dwelling must use a lightweight frame (steel or timber); roof cladding is capped at 20 kg/m2 and wall cladding at 220 kg/m2."
source_location: "2.0.4"
- claim: "The exempt dwelling must be simple in design; have a floor no more than 1 m above ground and a maximum height no greater than 4 m above floor level (no mezzanine); have independent points of supply for electricity and gas (where applicable); and 'the exempt dwelling CANNOT INCLUDE A SOLID FUEL HEATER'."
source_location: "2.0.5"
- claim: "Setback (Schedule 1A): the exempt dwelling must be 2 metres or more away from any residential building or legal boundary."
source_location: "2.0.3"
- claim: "On-site services: plumbing and drainage must connect to council water and wastewater systems where available; where no public system exists or capacity is insufficient, on-site water collection and wastewater systems (new or modified) can be used, and that work is also exempt from building consent."
source_location: "2.1.1"
- claim: "BUT resource consent may still be required 'Where there will be ON-SITE WASTEWATER DISPOSAL' - and also where NES-DMRU requirements are not met, or for earthworks (NES-DMRU regs 7 and 8; e.g. levelling a sloping site or adding fill to construct a building platform). Building consent may still be required where Schedule 1A conditions are not met, or where the site may be subject to a natural hazard (Building Act s72)."
source_location: "5.0.1, 5.0.2"
- claim: "NES-DMRU scope: a minor residential unit is defined as self-contained but ANCILLARY to a principal residential unit, held in common ownership on the same site. The NES-DMRU are enforced by regional and district councils and apply in residential, rural, mixed-use and Maori purpose zones where specified permitted activity standards are met."
source_location: "3.0.1, 3.0.2"
- claim: "NES-DMRU setbacks: minor dwelling at least 2 m from the principal dwelling. Residential zones: 2 m from front boundary and 2 m from side and rear boundaries. RURAL zones: 10 m from the front boundary and 5 m from side and rear boundaries. Coverage: principal dwelling + detached minor residential unit together cannot cover more than 50% of the site in residential zones (stormwater management)."
source_location: "3.0.3, 3.0.4"
- claim: "Electrical self-work: homeowners who intend to LIVE IN the exempt dwelling can do some of the electrical wiring themselves under the domestic exemption in the Electricity Act 1992 (s79); once completed the work must be inspected by an electrical inspector. Otherwise restricted building work must be done or supervised by LBPs and licensed plumbers, drainlayers, gasfitters and electrical workers."
source_location: "2.1.5, 2.0.6"
- claim: "Council obligations remain despite the exemption: PIM before work; council must advise whether elements are likely/unlikely/uncertain to meet the exemption (new Building Act s35A) - but 'This is not an approval process and homeowners can choose to build irrespective of council advice'; council must be notified on completion with as-built plans for building, plumbing and drainage; records of work, certificates of work and energy work certificates required; failure to provide documentation within 20 working days of completion may be fined. No council inspections and NO code compliance certificate."
source_location: "4.0.1, 4.0.3, 4.0.7, 4.0.8, 4.0.9"
- claim: "Scale: around 800 buildings up to 70 m2 were constructed each year when building consent was required; 'the government has indicated that it expects up to 13,000 small dwellings to be built in the first 10 years under the exemption.' Schedule 1 exemptions for SLEEPOUTS (BRANZ BU703) are a DIFFERENT exemption with different conditions - they affect what facilities can be included, likely total costs, and who can carry out the work."
source_location: "1.0.7, 1.0.10"Neobiome Intelligence relevance
This source constrains the design space rather than opening it. Three findings, in descending order of consequence.
1. The resource-consent exemption is a granny-flat rule, not a village rule
The NES-DMRU defines a minor residential unit as ancillary to a principal residential unit, in common ownership, on the same site. A community cannot build 30 exempt dwellings under it — each would need a principal residence to be subordinate to. This corroborates CR_046’s “one ≤70 m² detached minor unit per site”, now traceable to the named regulation rather than an AI-compiled register.
2. The resource-consent exemption lapses exactly on the off-grid case
§5.0.2 reinstates resource consent “where there will be on-site wastewater disposal”. A community with no mains sewer is definitionally that case. Note the trap: §2.1.1 says on-site water/wastewater work needs no building consent — a different instrument from the resource consent §5.0.2 requires. The two must not be conflated. This is consistent with, and sharpens, the existing D03 finding that on-site wastewater needs an RMA s15 discharge consent unless a regional permitted standard is met (CR_046).
3. The building-consent exemption forecloses two Neobiome technologies
It is a wood burner or the exemption — and earth walls are out entirely
- No solid-fuel heater (§2.0.5). An exempt dwelling cannot include one. This sits on a different axis from the existing permitted-activity entry (“wood burner outside a polluted airshed on >2 ha needs no discharge consent”, CR_046) — that is RMA discharge; this is the Building Act exemption. Both must hold, and here they conflict: taking the Schedule 1A exemption rules out wood heat in that dwelling.
- Earth-wall construction is excluded (§2.0.4). The frame “must be made of lightweight building products, being steel or timber.” Rammed earth and CSEB are load-bearing monolithic masonry with no steel or timber frame, so they fail the condition on its face — no cladding-mass arithmetic required. Earthsong’s own 350–400 mm rammed-earth walls (OT_093) would not qualify. A community choosing the exemption is choosing lightweight timber/steel construction.
What actually survives
The Building Act Schedule 1A exemption is a separate instrument from the NES-DMRU (BU704 is explicit: “These exemptions are separate from the Building Act Schedule 1 exemptions…”, and treats the two regimes in separate sections). So the ~$4,000/dwelling consent saving may still apply even where resource consent is required — that is the one bankable number here, and it is the model’s potential CapEx lever.
But whether it applies at community scale is unresolved. BU704 describes Schedule 1A dwellings as “new, stand-alone” (§2.0.2) without stating that a principal dwelling must exist, while the NES-DMRU explicitly requires one. If Schedule 1A stands on its own, a community banks ~$4,000 × N; if it inherits the ancillary requirement, the exemption is unusable at community scale. BU704 does not settle this → RT_338 (high).
Also usable now: rural NES-DMRU setbacks (10 m front / 5 m side+rear) are a harder spatial constraint than the Schedule 1A 2 m, and bear on the B4a archetype spacing guides; and the s79 self-wiring allowance is a genuine labour-cost lever for an owner-builder community.
Research targets
Documents to retrieve
- RT_339 — MBIE “Granny flats exemption: Guidance and resources” (council forms, step-by-step guides, checklists, fact sheets) + the NES-DMRU 2025 regulations themselves (Ministry for the Environment). The two primaries BU704 names in §6. These are what answer RT_338.
- RT_340 — BRANZ BU703 Sleepouts exempt from building consent — the Schedule 1 sibling pathway (≤30 m², no sanitary facilities), explicitly different conditions (§1.0.10). Low priority; a sleepout cannot be a dwelling.
Research gaps
- RT_338 (high) — Does Building Act Schedule 1A itself require a principal dwelling on the site? The decisive question for whether the ~$4,000/dwelling consent saving is available to a community at all. BU704 says “new, stand-alone” (§2.0.2); the NES-DMRU says “ancillary… same site” (§3.0.2). Needs the Schedule 1A text.
Notes
Authoritative BRANZ publication (not AI-prepared) — data_quality: high. Read via pdftotext -layout at ingest; all quoted conditions verified verbatim against the PDF.
Relationship to REG_001: REG_001 (MBIE Tiny Houses Guidance V5, Jan 2026) already noted that the Schedule 1A granny-flat exemption exists (≤70 m², no building consent, LBP required). BU704 is complementary, not duplicative — it supplies the actual Schedule 1A conditions (materials, heater, setbacks, services), the NES-DMRU resource-consent limb that REG_001 does not cover, and the on-site-wastewater carve-out. Neither source settles RT_338.
Connections
Links to
Referenced by