Model/backend/documents_parser
Khalim Conn-Kowlessar a736db3f4a Slice 101b: HP cert 0380 — cavity+EWI wall U + Table 11 cat-4 secondary
Two HP-specific cascade gaps blocking cert 0380:

(a) Cavity wall + filled cavity + external insulation:
    Cert 0380's `walls[0].description="Cavity wall, filled cavity and
    external insulation"` with `wall_insulation_type=6` +
    `wall_insulation_thickness="100mm"`. RdSAP 10 §4-4 (page 73) lists
    "cavity plus external" as a distinct insulation type code (6 in
    the API schema; 7 is "cavity plus internal"). The U-value is the
    composite U = 1 / (1/U_filled + R_ins) per §5.8 page 40 + Table 14
    R-value lookup, with the cascade-2-d.p. round matching the dr87
    worksheet's column display.

    For cert 0380: U_filled (age D)=0.7 + R_ins (100mm @ λ=0.04)=2.5
    → U_unrounded=0.2545 → rounded 0.25 (worksheet exact). Walls HLC
    14.87 → 11.6150 (= worksheet 11.6150). (37) total fabric heat
    loss 99.34 → **96.0889** (= worksheet 96.0889 EXACT).

    Added `WALL_INSULATION_CAVITY_PLUS_EXTERNAL: Final[int] = 6` and
    `WALL_INSULATION_CAVITY_PLUS_INTERNAL: Final[int] = 7` constants
    + `_WALL_INSULATION_LAMBDA_W_PER_MK = 0.04` default thermal
    conductivity. New `u_wall` branch fires when cavity + composite
    insulation type + non-zero thickness.

(b) SAP 10.2 Table 11 secondary fraction — missing cat-4 entry:
    The dict `_SECONDARY_HEATING_FRACTION_BY_CATEGORY` had entries
    for cats 1/2/3/5/6/7/10 but DID NOT include cat 4 (heat pump),
    despite the inline comment explicitly noting "Cat 4 (heat pump):
    0.00 (HP eff includes any secondary)". Cert 0380 lodges
    `secondary_heating_type=691` + `main_heating_category=4` (HP,
    PCDB idx 104568), so the cascade fell through to the DEFAULT
    fraction 0.10 — billing 547 kWh × 13.19 p/kWh = £72 as
    "secondary heating" that the worksheet correctly shows as £0.

    Added `4: 0.00` to the dict.

Effect on cert 0380 API path:
- walls HLC 14.87 → 11.62 (worksheet exact)
- (37) total HLC 99.34 → 96.09 (worksheet exact)
- main_heating_cost £282 → £314 (worksheet £316)
- secondary_heating £72 → £0 (worksheet £0)
- sap_continuous 87.62 → 90.48 (Δ -0.89 → +1.97 — over-correcting
  because hot-water cascade is still cascade-£66 vs worksheet £204
  including electric shower; HP HW-COP + electric-shower cost are
  the next slices).

No golden cert residual shifts (cohort certs don't lodge HP cat 4
or composite cavity+EWI walls).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-01 16:28:45 +00:00
..
handler address JTK review comments 2026-04-20 15:11:17 +00:00
tests Slice 101b: HP cert 0380 — cavity+EWI wall U + Table 11 cat-4 secondary 2026-06-01 16:28:45 +00:00
__init__.py Map to RdSapSiteNotes from site notes JSON 🟥 2026-04-16 13:54:03 +00:00
db_writer.py include updating epc_property_data to pashub to ara workflow 2026-04-29 09:55:14 +00:00
elmhurst_extractor.py Slice 99d: surface PV array from Elmhurst Summary §19.0 2026-06-01 16:28:45 +00:00
extractor.py Handle wall thickness "Unmeasurable" 🟩 2026-04-30 16:41:16 +00:00
local_runner.py update local runner to work for elmhurst 2026-04-24 14:01:36 +00:00
parser.py load ecmk site notes to db 2026-04-29 11:20:47 +00:00
pdf.py update local runner to work for elmhurst 2026-04-24 14:01:36 +00:00