mirror of
https://github.com/Hestia-Homes/Model.git
synced 2026-07-19 17:03:02 +00:00
3f69c4be02
Captures the calc-facing ventilation-type gap (older RdSAP mappers drop mechanical_ventilation_kind), the FE-side Main Fuel display, the sweep survivor clusters, and the predicted-property display path — all separate from ADR-0037. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
56 lines
3.2 KiB
Markdown
56 lines
3.2 KiB
Markdown
# Follow-ups from the full-SAP baseline-downgrade work (ADR-0037)
|
||
|
||
Open items surfaced while fixing the full-SAP mapper / portfolio-796 downgrades.
|
||
Each is **separate from** the full-SAP fix (`fix/baseline-downgrades`).
|
||
|
||
## 1. Older RdSAP mappers drop `mechanical_ventilation_kind` (calc-facing)
|
||
|
||
**Severity: accuracy bug for MEV/MVHR dwellings.**
|
||
|
||
`mechanical_ventilation_kind` (the natural / MEV / MVHR ventilation **type**) is
|
||
mapped in **only `from_rdsap_schema_21_0_1`** ([mapper.py:2650], via
|
||
`_api_mechanical_ventilation_kind`). The other six API mappers —
|
||
`from_rdsap_schema_17_0/17_1/18_0/19_0/20_0_0/21_0_0` — build
|
||
`SapVentilation(sheltered_sides=…)` and **drop** the cert's `mechanical_ventilation`
|
||
field. (The full-SAP path maps it via `_sap_17_1_ventilation` — not affected.)
|
||
|
||
- For **natural-ventilation** certs (`mechanical_ventilation = 0`, e.g. UPRN
|
||
100020603823 / property 726605) it's **benign** — unmapped → `None` defaults to
|
||
natural in the §2 cascade.
|
||
- For **MEV/MVHR** certs (`mechanical_ventilation ≠ 0`) the calculator treats the
|
||
dwelling as **naturally ventilated**, getting the SAP §2 ventilation cascade
|
||
(and any heat recovery) wrong → mis-scored SAP.
|
||
|
||
The granular **counts** (fans/flues/vents) are *not* a bug: older RdSAP open-data
|
||
certs don't lodge them, and the calc correctly uses RdSAP Table-5 age defaults.
|
||
`percent_draughtproofed` is mapped (top-level) and read by the calc.
|
||
|
||
**Fix:** mirror `mechanical_ventilation_kind=_api_mechanical_ventilation_kind(schema.mechanical_ventilation)`
|
||
into the six older RdSAP mappers. **Calc-facing → validate** with the RdSAP-21.0.1
|
||
corpus (must hold 73.3% / MAE 0.774) plus an Elmhurst-anchored MEV/MVHR cert (the
|
||
corpus is natural-vent-dominated, so add a mechanical-vent `RealCertExpectation`).
|
||
Quantify blast radius: count older-RdSAP certs with `mechanical_ventilation ≠ 0`.
|
||
|
||
## 2. FE "Main Fuel: Unknown" is FE-side, not a Model mapper gap
|
||
|
||
`main_fuel_type` (the gov fuel **code**) **is** populated Model-side — UPRN
|
||
10093412452 (709791) → `1`, UPRN 100020603823 (726605) → `26` — and is persisted
|
||
(`epc_main_heating_detail.main_fuel_type`). So the panel's "Main Fuel: Unknown"
|
||
is the **front-end** either not mapping the code → fuel name or reading a field we
|
||
don't populate. Needs an FE-repo (Drizzle/Next) check, not a Model change.
|
||
|
||
## 3. Survivor clusters from the post-fix population sweep
|
||
|
||
`scripts/hyde/case_a_population_sweep.py`: the representative sample rebaselined
|
||
cleanly (0 survivors), but the worst-old-drop sample held **28 survivors**
|
||
(lodged A/B → new C/D, 15–25 SAP) in tight UPRN clusters (new-build blocks),
|
||
spanning multiple schemas (16.0/16.1/17.1/18.0.0) and heating types. No single
|
||
mapper-gap signature → likely genuine SAP-2012→10.2 drops for very-high-lodged
|
||
new-builds, but **triage one in Elmhurst** to confirm genuine vs a residual calc
|
||
issue before trusting the cohort.
|
||
|
||
## 4. Predicted-property display path (e.g. property 721167)
|
||
|
||
721167 has **no lodged EPC** (predicted). Its Heating-Control / Main-Fuel /
|
||
Ventilation Unknowns come from the prediction + landlord-override **overlay** not
|
||
populating the display fields — a separate path from the lodged-cert mappers.
|