Closes cert 2636 to spec floor (Δ +0.5167 → +0.0323) by accepting
both the EPC schema enum-as-string ("0") AND the Elmhurst Summary
mapper's descriptive form ("House") for the cantilever-detection
property-type gate at `heat_transmission.py:768`.
Root cause: slice 102f-prep.9 (commit 06b4ef3d) added cantilever
detection gated on `epc.property_type == _PROPERTY_TYPE_HOUSE` where
`_PROPERTY_TYPE_HOUSE = "0"`. That matches the API mapper's encoding
(schema enum), but the Summary mapper produces "House" (descriptive)
and the hand-built worksheet fixtures also use "House" — so neither
triggers the gate and the cantilever path silently no-ops on the
Summary path. Cert 2636's worksheet (28b) "Exposed floor Main 3.74
× 1.20 = 4.4880" is the cantilever — without surfacing it the
cascade missed 4.488 W/K of floor heat loss.
Three-encoding origins:
- API mapper: property_type='0' (schema enum-as-string)
- Summary mapper: property_type='House' (descriptive from §1)
- Hand-built fixtures: property_type='House' (legacy convention)
Fix: replace the equality check with a `_is_house()` helper that
accepts the {"0", "House"} frozenset. Centralised so future
property-type sensitive gates can call the same helper.
Forcing function: cert 2636 first-attempt Summary SAP closes from
Δ +0.5167 (after S0380.12 walls fix) to Δ **+0.0323** — within the
±0.07 ASHP-cohort spec floor. `floor_w_per_k` moves from 19.1982
(ground floor only) to 23.6862 (ground 19.20 + cantilever 4.49 =
worksheet (28a) + (28b) exact match).
Cohort closure status (6 of 7 ASHP certs at spec floor):
cert Δ vs worksheet spec floor?
0380 +0.0594 ✓
0350 +0.0458 ✓
2225 +0.0441 ✓
2636 +0.0323 ✓ ← this slice
3800 +0.0442 ✓
9285 +0.0502 ✓
9418 +2.5973 ✗ (Daikin EDLQ05CAV3 — final cert)
Boiler hand-built parity verified intact: 5 hand-built cohort certs
(000474, 000477, 000480, 000490, 000516) all use property_type=
"House" and now also fire the cantilever gate, but none have
floor1_area > floor0_area + 1m² (the cantilever-area trigger) so
their cascade output is unchanged. Regression suite 683 pass + 10
fail (= handover baseline 669 + 10 + 17 new GREEN tests across
S0380.2..S0380.13).
Pyright net-zero on edited files:
domain/sap10_calculator/worksheet/heat_transmission.py: 13
(baseline; no new errors)
backend/documents_parser/tests/test_summary_pdf_mapper_chain.py: 0
Spec / precedent refs:
- Slice 102f-prep.9 (commit 06b4ef3d) — RdSAP cantilever-exposed-
floor detection (originally API-only via `property_type=="0"` gate).
- SAP 10.2 Table 20 — U_exposed_floor (age D + no insulation →
1.20 W/m²K, the cohort's cantilever U-value).
- Cert 2636 worksheet `dr87-0001-000898.pdf` line refs (28a)+(28b)
sum 23.6862 W/K (exact cascade match after this slice).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
395ad30c48