Source
https://www.branz.co.nz/energy-efficiency/house-insulation-guide/ — original source (opens in a new tab; the file is not redistributed)
Summary
The BRANZ House Insulation Guide, 6th edition (2023) is the authoritative practical NZ reference for insulating housing to Building Code clause H1 Energy Efficiency (and E3 Internal Moisture), updated for H1/AS1 + H1/VM1 5th edition amendment 1. It sets out the minimum construction R-values by climate zone (the code-minimum thermal envelope), the six NZ climate zones, insulation-material properties, installation practice, window/glazing R-values and solar heat gain, thermal-bridging research, retrofit options, overheating and embodied carbon. For Neobiome Intelligence its value is as the primary grounding of the building-standard baseline (D04): it pins the code-minimum envelope for the pilot region (Nelson/Tasman = Climate Zone 3 — Roof R6.6, Wall R2.0, slab R1.5, windows R0.46), the baseline that CR_017’s high-performance/passive multipliers improve on. Its most important caveat is empirical: real NZ walls average 34% framing (vs the 14–18% assumed in compliance), so as-built R-values run materially below nominal.
Key claims
See key_claims frontmatter (7 claims, cited to section/table). R-values are building-physics inputs (envelope thermal resistance), not energy-demand (kWh) figures.
Neobiome Intelligence relevance
- Code-minimum thermal-envelope baseline (D04). The authoritative primary for the NZ Building Code H1 minimum R-values by climate zone — the “code-minimum” envelope that CR_017’s high-performance (×0.50) and passive-house (×0.12) space-heat multipliers improve upon. Pilot Zone 3 (Nelson/Tasman): Roof R6.6, Wall R2.0, slab-on-ground R1.5, suspended floor R2.5, windows/doors R0.46, skylights R0.54. Grounds CR_017’s compiled synthesis with a primary source. OT_057
- ⚠ Thermal-bridging derate caveat. BRANZ ER53 found real walls average 34% framing (vs the 14–18% assumed in compliance calcs), plus ~3% missing insulation — so nominal R-values overstate real performance. NI envelope assumptions should treat code R-values as optimistic; note that CR_015’s empirical demand already embeds real-world performance. OT_057
- Sustainable insulation options. Sheep’s wool (natural, renewable, NZ-sourced), wood fibre and recycled-content products are lower-embodied-carbon choices relevant to a low-impact / self-sufficient community’s material selection. OT_057
- Emerging cooling demand. Overheating is unregulated by H1 yet rising (Auckland could gain ~a month of hot days by 2050) — a forward caveat for the demand side: a warming-climate community may need shading/ventilation design and incur growing heat-pump cooling load. OT_057
- ⚠ Scope. R-values are envelope thermal resistance, not kWh demand; NI’s space-heat demand comes from CR_015 (empirical) + CR_017 (multipliers). This source grounds the baseline envelope and supplies the climate-zone framework, the thermal-bridging derate, and material options — not the demand magnitude directly.
Research targets
Documents to retrieve
- (none — this guide resolves no open target; it is the primary authoritative grounding for CR_017’s code-minimum baseline.)
Research gaps
- (none new. An as-built thermal-bridging derate factor for NI envelope modelling was considered but not raised — CR_015’s empirical space-heat demand already embeds real-world envelope performance, so a nominal-vs-as-built R-value correction is not needed for the current NI approach.)
Connections
Links to
Referenced by