Source
https://www.branz.co.nz/pubs/research-reports/sr495/ — original source (opens in a new tab; the file is not redistributed)
Summary
BRANZ Study Report SR495 (2024) is the first report from HEEP2 — the long-awaited successor to the 1999–2005 HEEP1 study — covering winter comfort, heating behaviour and measured indoor temperatures across a national sample of over 750 households. The headline is a mixed picture of progress and persistence: living areas are now warmer than HEEP1 found (mean evening temperature just under 20°C, reflecting two decades of heat-pump uptake), but bedrooms remain cold (mean overnight 16.5°C, below the WHO 18°C minimum), over two in five bedrooms are never heated, and dampness, condensation and mould are still widely reported. For Neobiome Intelligence it is the modern validation of the cold-homes case: it refreshes OT_037’s 2005 temperatures and LIT_044’s damp/mould baseline, confirming that building-fabric performance and whole-house (not just living-room) warmth remain the habitat priority.
Key claims
- claim: "HEEP2 (BRANZ SR495, Anderson, White & Jones 2024) is the successor to HEEP1 (1999–2005); it draws on a national sample of over 750 households. This report covers winter comfort, heating and indoor temperatures and is a preliminary analysis — the full HEEP2 energy end-use results are still to come."
source_location: "Abstract; §1; §7 methodology"
- claim: "Mean (average) temperature in living areas in the evening was just under 20°C, while the mean temperature overnight in occupied bedrooms was 16.5°C — bedroom temperatures remain below recommended healthy levels (the report references an 18°C healthy threshold with 16°C and 12°C lower thresholds)."
source_location: "Abstract; Figure 22 (living areas, Aug–Sep); Figure 23 (occupied bedrooms vs 18/16/12°C thresholds)"
- claim: "Dampness (33%), condensation (75%) and mould (48%) were frequently reported by households; 92% of those reporting damp/condensation/mould and wanting their house warmer felt their house was colder than they would like."
source_location: "§Damp, condensation and mould (p.17); §6"
- claim: "Most households reported heating their living areas, but heated their bedrooms far less — over 2 in 5 (more than 40%) bedrooms were never heated; bedrooms occupied by young children were more likely to be heated (an apparent prioritisation of young children's bedroom temperatures)."
source_location: "Abstract; §Heating rooms in winter (p.20); Figure 18"
- claim: "1 in 20 households (5%) said they had gone without heating at some time in the last year — an indicator of energy hardship."
source_location: "Abstract; §Attitudes to winter heating"
- claim: "The study used a Full sample (full surveys plus indoor-temperature monitoring on a subset of households) and a Medium sample (target ~130, predominantly owner-occupied — only ~10% rented); results are reported for the Full and Medium samples combined."
source_location: "§7.1 Characteristics of Full vs Medium samples (p.24); §7 methodology"Neobiome Intelligence relevance
- D04 — modern NZ winter-warmth baseline (the cold-homes case, refreshed). Two decades on from HEEP1, living areas have warmed to ~20°C in the evening (heat-pump uptake) but bedrooms remain cold at 16.5°C overnight (below WHO 18°C), with damp 33% / mould 48% / condensation 75% still widely reported OT_042. This is the current-data confirmation that whole-house thermal performance — not just living-room heating — is the habitat priority, complementing the housing-health case in LIT_044.
- Refreshes OT_037’s vintage flag. It confirms the living-area warming that CR_015’s 0.843 modernisation factor assumed, while showing the cold-bedroom and damp/mould problems persist OT_042. (But this is the comfort/temperature report only — HEEP2’s energy end-use split is still pending, so OT_037 remains the demand-split primary for now.)
- Energy hardship signal. 5% going without heating and >40% of bedrooms never heated quantify the under-heating a self-sufficient, affordable-warmth community design aims to eliminate OT_042.
Research targets
Documents to retrieve
- HEEP2 full energy end-use results (forthcoming BRANZ outputs) — the modern refresh of HEEP1’s 34/29/37 end-use split, 11,410 kWh/dwelling total and 7,800 kWh electricity (still carried via OT_037); the priority update for the model’s ② demand cells. (RT_098 — stays open until these are published.)
Research gaps
- A HEEP1-vs-HEEP2 like-for-like comparison of living-room evening temperatures (room/time definitions differ slightly between studies) to quantify the warming precisely rather than approximately.
Connections
Links to
Referenced by
Sources (5): OT_037 · OT_043 · OT_048 · OT_123 · OT_133
EDT domains (1): D04: Sustainable Habitat & Building Technology
Concepts (1): Healthy Housing — Warmth, Dryness & Wellbeing