Implements SAP10.2 Appendix J Table 3c row 1 (Instantaneous combi, two-
profile EN 13203-2 / OPS 26 tests):
(61)m = (45)m × [r1 + DVF × F3] × fu + [F2 × n_m]
DVF (Daily Volume Factor) is piecewise in V_d,m, gated on the test
profile pair: M+L (PCDF separate_dhw_tests=2) or M+S (=3). Helper
`_table_3c_dvf` keeps the spec's piecewise branches close to the
formula in `combi_loss_monthly_kwh_table_3c_two_profile_instantaneous`.
Tests:
- 000477 element-wise LINE_61 pin via Table 3c (PCDB 18118 lodges
r1=0.015, F2=0.0, F3=0.00014; profile_pair=M+L). Closes 000477's
combi-loss component at abs=1e-3 against U985 PDF.
- Parametrized DVF boundary table for M+L (V<100, V=100, V=199.8,
V>199.8) and M+S (V<36, V∈[36,100.2], V>100.2) at abs=1e-9.
Citation fix: parser docstring updates the BRE PCDF Spec reference from
the placeholder "v1.0 §7.11" to the actual Rev 6b (12 May 2021) Gas and
Oil Boiler Table, pp. 14-15 (now landed at docs/sap-spec/). Notes that
PCDF field 48's encoding (1=schedule 2 → profile M; 2=schedules 2+3 →
M+L; 3=schedules 2+1 → M+S) drives the Table 3b/3c row selection, and
that r2 (field 55) is lodged but spec-excluded from SAP.
Table 3c rows 2-5 (storage-FGHRS / storage-combi variants) and Table
3b rows 2-5 stay deferred — symmetric "row 1 only" coverage until a
fixture exercises them.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Lodges the missing cert fields on 000477 build_epc to match U985 PDF:
- sap_windows = SECTION_6_VERTICAL_WINDOWS (was empty)
- low_energy_fixed_lighting_bulbs_count = 9 (was None)
- sap_heating.main_heating_details with PCDF index 18118 (was default)
- sap_heating.secondary_heating_type = 691 (was None)
- sap_heating.number_baths = 0 (PDF lodges 0 baths; was None → defaulted to "has bath"=True)
`make_sap_heating` accepts a new `number_baths` kwarg to surface that
field — it lives on SapHeating but wasn't exposed before.
Impact: 000477 SAP integer 71 → 66 (PDF 65, Δ +6 → +1); cost £599 →
£707 vs PDF £732 (Δ -22% → -3.5%); useful 9059 → 10067 vs PDF 10111
(matches to <0.5%).
Remaining +1 SAP integer delta is the **Table 3c two-profile combi-
loss override** — not yet implemented. PCDB 18118 (Vaillant ecoTEC
sustain 24) lodges separate_dhw_tests=2 → spec Appendix J §J3 uses
both Profile M (F1, R1) and Profile L (F2, R2) loss factors. Our
override gate (`_pcdb_table_3b_combi_loss_override`) only accepts
separate_dhw_tests==1 → falls back to Table 3a keep-hot time-clock
600 kWh/yr default = 25x overshoot vs the fixture-pinned ~24 kWh/yr.
The same gap blocks 000480 (PCDB 16839 — but actually wait, 16839 is
in 000490 too and that already closes — needs checking), 000487 (PCDB
18119), and 000516 (PCDB 18118).
Test pin `test_elmhurst_000477_end_to_end_sap_score_matches_pdf`
xfail (strict) with rationale pointing at Table 3c. Re-enables when
the override implements.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Replaces the SAP 10.3 §13 rating constants in `worksheet/rating.py`
with SAP 10.2 values per ADR-0010 (active spec target is SAP 10.2,
14-03-2025; spec changed to SAP 10.3 only as of 13-01-2026 which
hasn't been adopted):
Energy Cost Deflator 0.36 → 0.42
Linear branch slope 16.21 → 13.95 (SAP = 100 − slope × ECF)
Log branch intercept 108.8 → 117.0 (SAP = intercept − slope × log10(ECF))
Log branch slope 120.5 → 121.0
The two errors were near-cancelling on the Elmhurst cohort (low-cost
combi-gas dwellings on the linear branch): the wrong deflator made
our ECF ~14% low, and the wrong linear slope made our SAP drop per
unit ECF ~16% high. Their product was close to the spec but not
exactly — leaving 000490 stuck 1 SAP integer over PDF after the
other component closures (Appendix L, secondary heating, ventilation,
pumps_fans) had brought cost to within £0.04 of PDF.
Final cohort SAP integer status — **both fixtures hit delta=0**:
000474: integer 62 = PDF 62 (continuous 61.91 vs PDF 62.26, Δ -0.35)
000490: integer 57 = PDF 57 (continuous 57.40 vs PDF 57.40, Δ -0.002)
000490 e2e SAP integer ceiling tightened 1 → 0.
Updated 8 internal rating + calculator tests that pinned the SAP 10.3
constants (test_rating.py, test_calculator.py, test_bre_worked_
examples.py). All 685 tests green; 0 xfail.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Replaces the static `_DEFAULT_PUMPS_FANS_KWH_PER_YR = 130` for
gas-combi main heating systems with the SAP10.2 Table 4f cascade
value: 115 kWh/yr (230c central heating pump, post-2013 install) +
45 kWh/yr (230e main heating flue fan, balanced/condensing) = 160.
Selection keyed by `main.main_heating_category` — currently only
category 2 (Gas-fired boilers); other categories fall back to the
legacy 130 sentinel pending the next fixture exercising them.
Adds `_PUMPS_FANS_KWH_BY_MAIN_CATEGORY` lookup. Both `CalculatorInputs.
pumps_fans_kwh_per_yr` and the `_fuel_cost(...)` pumps_fans arg now
share the same per-cert value.
E2E pins: new parametrized test
`test_elmhurst_end_to_end_pumps_fans_kwh_matches_u985_worksheet`
asserts `result.pumps_fans_kwh_per_yr == 160` at abs=1e-3 for the
2 e2e fixtures (000474, 000490).
Impact on 000490: cost £803.62 → £807.58 (PDF £807.54, Δ +£0.04 ≈ 0%);
continuous SAP 57.77 → 57.57 (PDF 57.40, Δ +0.17 — was +0.38).
SAP integer still 58 vs PDF 57 — remaining residual is the SAP
rating constants (rating.py uses SAP 10.3 deflator 0.36 / slope
16.21/120.5; PDF lodges SAP 10.2 0.42 / 13.95/121) — next slice.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Surfaces four cert lodgements that the §2 ventilation cascade was
missing on the cert→inputs path. Without them, `cert_to_inputs` was
defaulting:
- extract_fans_count → 0 (PDF: 1-2 fans per fixture)
- percent_draughtproofed → 0 (PDF: 75-100% per fixture)
- sheltered_sides → 2 (PDF: 1-3 per fixture — hardcoded TODO)
- has_suspended_timber_floor → False (PDF: True on 000477/000487)
Net effect on (25)m monthly effective ACH ranged from -19% (000477)
to +5% (000490) → propagated 1:1 through HLC × ΔT → useful space heat
→ main + secondary fuel kWh → cost / SAP integer.
Schema:
- `SapVentilation` gains 4 new optional fields: `sheltered_sides`,
`has_suspended_timber_floor`, `suspended_timber_floor_sealed`,
`has_draught_lobby`. RdSAP cert lodges these but the type didn't
surface them.
- `cert_to_inputs.cert_to_inputs` reads them when set; falls back to
the SAP10.2 §2 worst-case defaults (sheltered=2, no timber floor,
no draught lobby) when the cert hasn't lodged. Removes the long-
standing `sheltered_sides=2` hardcode + 4 TODOs.
- `make_minimal_sap10_epc` accepts a `sap_ventilation` kwarg.
Per-fixture build_epc() updates lodge the U985 PDF values verbatim.
E2E pin: new parametrized test
`test_elmhurst_cert_to_inputs_monthly_infiltration_ach_matches_u985_
worksheet` asserts `inputs.monthly_infiltration_ach[m] == LINE_25_
EFFECTIVE_ACH[m]` at abs=1e-3 across all 6 fixtures + 12 months
(72 assertions). All pass.
Useful space heating drift:
000474: useful 10821.69 → 10765.85 (Δ -55.8 kWh vs PDF 10612.86 → +1.4% over, was +2.0%)
000490: useful 11262.05 → 11184.06 (Δ -78.0 kWh vs PDF 11183.28 → +0.007% — essentially exact)
SAP integer status:
000474: 62 = PDF 62 (delta 0) ✓
000490: 58 vs PDF 57 (delta 1; continuous 57.77 vs 57.40)
— remaining residual is pumps_fans hardcoded at 130 kWh
vs PDF 160 (Table 4f cascade not yet implemented → -£4 cost
+ 0.3 continuous SAP). Next slice.
Tightens `result.secondary_heating_fuel_kwh_per_yr` pin abs=10 → abs=0.1
(was loose to absorb the +0.7% useful overshoot which has now closed).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Lodges `secondary_heating_type=691` (Electricity Electric Panel) on
000490 `build_epc()` to match the U985 worksheet's "Secondary Heating:
Electricity Electric Panel, convector or radiant heaters, SAP Code 691,
Efficiency 100%". Pre-fix the cert lodged no secondary system →
`_secondary_fraction` returned 0.0 → all useful space heat routed to
main 1 → main_fuel +1357 kWh over PDF, secondary -1118 under PDF, cost
-£104 under PDF (-12.9% residual).
Post-fix: Table 11 fraction 0.1000 for gas-combi category cascade fires
→ main 1 = 11491.89 kWh, secondary = 1126.21 kWh. Total cost £807.42
vs PDF £807.54 (Δ -£0.12, -0.015%). SAP integer 58 vs PDF 57 (delta 1,
was 6); continuous 57.57 vs 57.40 (delta 0.18).
E2E test updates:
- New worksheet-level pin `result.secondary_heating_fuel_kwh_per_yr ≈
U985 (215) = 1118.3275` at abs=10 (loose — absorbs the +0.7% upstream
useful space heating overshoot which propagates 1:1 to (215). Tightens
to abs=1e-3 when the useful bias closes).
- Per-fixture constant `LINE_215_SECONDARY_HEATING_FUEL_KWH = 1118.3275`.
- 000490 SAP integer ceiling tightened 3 → 1; continuous 3.0 → 0.5.
- Removed xfail on `test_elmhurst_000490_end_to_end_sap_score_currently_
within_3_points` and `test_000490_cert_to_inputs_fuel_cost_closes_to_
within_5pct` — both now pass.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
SPEC_COVERAGE:
- §5 row: note new `annual_lighting_kwh` public leaf + InternalGainsResult
field + per-fixture U985 (232) abs=1e-4 pin across all 6 Elmhurst fixtures.
- Appendix L row: "Full (cost + gains)" — closes both sides via the same
L1-L11 cascade; legacy heuristic noted with rip-pending callsites.
ADR-0010 Amendment "Appendix L lighting (2026-05-22)":
- Two engine bugs surfaced + fixed: cosine modulation integral (uniform
+0.146% bias from continuous-formula vs Σ(L11 monthly)) and cert EPC
under-lodgement (`build_epc()` skipped bulb counts + windows).
- 000474 hits SAP integer delta=0 (first Elmhurst fixture across the gate).
- 000490 SAP integer + fuel cost xfailed (strict) — Appendix L direction
correct, other components broken (fuel pricing, Table D1-3 Ecodesign,
main heating +2.5%). Tracked as next ticket.
- Golden cohort PE tolerance widened 30→35 with rationale.
- Deferred work: cohort SAP-integer residual hunt, heuristic deletion,
RdSAP→API integration test (end-state e2e harness).
`predicted_lighting_kwh` deprecation note: cite ADR-0010 amendment; name
the two legacy callsites (`domain.ml.ecf`, `domain.ml.transform`) that
block deletion.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Closes the +9.2% cost residual on 000474 by swapping the legacy
`predicted_lighting_kwh` heuristic (9.3 × TFA × bulb-share) for the
spec-faithful Appendix L L1-L11 cascade that already drove §5 (67)
internal gains. Single source of truth via `InternalGainsResult.
lighting_kwh_per_yr`; the cost side and the gains side now derive
from the same monthly distribution.
Engine bug found during the wire-up: `annual_lighting_kwh` was
returning the L1-L9 continuous formula value (E_L), but the SAP10.2
worksheet lodges line ref (232) as Σ(L11 monthly distribution).
Discrete cosine integral Σ(n_m × factor) / 365 = 0.998539, not 1.0
exactly — caused a uniform +0.146% bias across all 6 Elmhurst
fixtures. Fixed by factoring a private `_lighting_monthly_kwh` and
having `annual_lighting_kwh` sum it directly. Synthetic S1 pin
updated 189.152079 → 188.875713 (post-modulation).
Cert-side updates: lodge `low_energy_fixed_lighting_bulbs_count` +
`sap_windows` on 000474 / 000490 `build_epc()` so the cert→cascade
path receives spec-faithful inputs (was defaulting to L5b/L8c +
C_daylight=1.433 no-bonus). Per-fixture `LINE_232_LIGHTING_KWH_PER_YR`
constants pin each U985 PDF value at 4 d.p.
E2E pin updates (per feedback-e2e-validation-philosophy: components
validate the engine; SAP integer = delta 0 is the integration gate):
- 000474 SAP integer ceiling tightened 3 → 0 (lands at 62 = PDF 62
exactly); continuous 3.5 → 0.5 (lands at 0.09)
- 000490 SAP integer + fuel-cost tests xfail with rationale —
Appendix L direction is correct (lighting closes 614→171 = PDF
171.4217), but cost residual widens past 5% / SAP delta widens
3→6 due to other broken components (fuel pricing, Table D1-3
Ecodesign, main heating +2.5%). Re-enable when those close.
- Golden fixtures `_PE_TOLERANCE_KWH_PER_M2` widened 30 → 35 to
absorb the elec-PEF × lighting-Δ contribution (~4 kWh/m²) on a
non-Elmhurst cohort whose pre-existing residual already sat near
-28 kWh/m² from unrelated components.
Component validation: `result.lighting_kwh_per_yr == PDF (232)` to
abs=1e-4 for 000474 (139.9452) + 000490 (171.4217); §5 worksheet-
level pin on `InternalGainsResult.lighting_kwh_per_yr` covers all 6
Elmhurst fixtures at the same tolerance. Existing §5 (67) LINE_67
monthly tuple tests remain green (refactor preserves monthly W
distribution).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Surfaces the SAP10.2 Appendix L L1-L12 annual lighting kWh as a public
free fn alongside lighting_monthly_w. Refactors lighting_monthly_w to
compose it. One source of truth shared by the §5 gains side and the
forthcoming cost side (inputs.lighting_kwh_per_yr) — slice 2 wires
internal_gains_from_cert + cert_to_inputs.
Synthetic L1-L12 test pins a hand-computed dwelling
(TFA=100, N=2.0, C_L=10000, ε=100, D=1.0) at 189.152079 kWh, abs=1e-3.
6-fixture LINE_67 conformance tests (Elmhurst 000474..000516) act as a
regression check on the monthly cosine + 0.85 internal-fraction
composition — all green.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Closes the residual ~1.2% on 000474 HW kWh that slice 1 left (PCDB
Table 3b combi loss landed (61) correctly but the divisor was still
the scalar PCDB summer efficiency 87.0%). Slice 2 promotes that
scalar to the SAP10.2 Appendix D §D2.1 (2) Equation D1 monthly
cascade — η_water,monthly = (Q_space + Q_water) / (Q_space/η_winter
+ Q_water/η_summer) — and folds it into the cert_to_inputs flow:
- worksheet/water_heating.py: water_efficiency_monthly_via_equation_
d1(...) — pure function over winter/summer efficiencies + (98c)m
× (204) + (64)m monthly tuples. Implements the spec's two early-
outs (η_summer ≥ η_winter → all months = η_summer; zero-demand
months → η_summer).
- rdsap/cert_to_inputs.py: splits _hot_water_fuel_kwh_per_yr (now
removed) into:
- _water_heating_worksheet_and_gains: runs §4 (45..65) early so
§5/§7/§8 can consume (65)m heat gains.
- _apply_water_efficiency: invoked after §8 produces (98c)m, picks
monthly cascade for PCDB-tested combis with distinct winter/
summer effs, falls back to scalar divisor otherwise.
Pulled secondary_fraction_value computation forward of §4 so the
post-§8 Q_space = (98c)m × (204) derivation has it in scope.
Outcomes (closes the §10a slice-2 deferred §4 HW debt):
- 000474 HW kWh: 2622 → 2320 (slice 1) → 2292 ✓ matches PDF 2292
to 0.0%. SAP delta 4 → 3 (ceiling tightened 4 → 3).
- 000490 HW kWh: 3028 → 3028 (slice 1 no-op, no PCDB Table 3b
data) → 2847 ✓ matches PDF 2851 to 0.1%. SAP delta 2 → 3
(ceiling loosened 2 → 3 — the closer HW kWh exposes spec-version
drift on the 000490 cost figure that PDF lodged under cert-
assessor era prices per ADR-0010 §3).
- 486 tests passing across the domain package; 13 pre-existing
pyright errors on cert_to_inputs (no net new from this slice).
Remaining 000474 +9% cost residual is Appendix L lighting (528 vs
~169 back-derived) — separate ticket per project memory
`project_section_4_hw_next_ticket` "secondary upstream" note.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Wires the §10a Fuel costs worksheet block (slice 1's orchestrator)
into the cert → calculator pipeline:
- CalculatorInputs.fuel_cost composite slot (default zero sentinel
for synthetic-test constructions that don't supply one).
- cert_to_inputs._fuel_cost precompute — resolves Table 32 prices
per end-use, calls additional_standing_charges_gbp per Table 12
note (a) for gas/off-peak gating, calls the fuel_cost orchestrator.
Off-peak certs return a zero FuelCostResult sentinel so the legacy
scalar fuel-cost-per-kWh fallback fires; Table 12a high-rate
fraction split + Table12aSystem mapping is deferred to a future
§10a follow-up slice.
- calculator delegates total_cost / per-end-use cost intermediate
dict entries to inputs.fuel_cost when the precompute is non-zero;
falls back to the legacy inline kWh × price math for synthetic
CalculatorInputs constructions (will be removed when the test
corpus migrates to fuel_cost=).
Outcomes:
- 000490 SAP rating ceiling tightened 6 → 2 (marquee close-out:
the cost gap was wrong-table + missing-standing-charges, not the
spec-version drift the handover suspected).
- 000474 SAP rating ceiling loosened 2 → 4 (post-§10a Table 32 +
standing-charge fix exposes upstream §4 HW kWh + Appendix L
lighting overestimates that the wrong pre-§10a prices had been
masking). §4 HW worksheet tightening is the next ticket.
- Golden corpus SAP tolerance widened 7 → 11 — Table 32 oil price
rose +55% (4.94 → 7.64 p/kWh) which moves oil-heated certs whose
lodged actual_sap pre-dates Table 32 (ADR-0010 §3 Validation
Cohort discipline).
- 2 new cert-round-trip conformance tests on test_fuel_cost.py
(000474 within existing e2e tolerance; 000490 within 5%).
660 tests passing across the domain package. 0 net new pyright
errors on touched modules.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Pins the API JSON → EpcPropertyDataMapper → CalculatorInputs chain for the 4 corpus PCDB-listed golden certs. Asserts (a) `main_heating_index_number` survives the mapper hop, (b) `cert_to_inputs` resolves Table 105 record by that ID and applies the winter efficiency. Catches future regressions where a mapper change might drop the PCDB pointer silently.
Confirms the API → domain → calculator chain works end-to-end without any new domain object field — `MainHeatingDetail.main_heating_index_number` has existed since schema 17_1 and all mapper paths from 17_1+ pass it through verbatim.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
PDF "PCDF boiler reference: 10328 Vaillant Ecotec Pro 88.20%" lodgement → fixture now sets `main_heating_index_number=10328` + `main_heating_data_source=1` per the API's standard PCDB-lodgement shape. cert_to_inputs PCDB precedence cascade picks up Table 105 record 10328 (winter eff 88.2%, summer 79.6%) and overrides the Table 4a category-2 default.
make_main_heating_detail extended to expose main_heating_index_number / main_heating_data_source / sap_main_heating_code kwargs so fixtures can lodge PCDB pointers without hand-building MainHeatingDetail.
000490 e2e impact:
- main_heating_fuel: 14334 → 13001.3 kWh (PDF 13003.85 — gap closes to <0.1%, was +10%)
- HW fuel: 3090.47 → 3028.27 kWh (PDF 2850.57 — gap closes +8.4% → +6.2%)
- total_fuel_cost: £756.99 → £706.23 (PDF £807.54 — diverges -6.3% → -12.5%, ADR-0010 §3 spec-version artifact)
- SAP rating: 60 → 63 (PDF 57 — +3 → +6)
The fuel-kWh tightening is the spec-faithful direction. The cost / SAP residuals widen because the cert pre-dates the 14-March-2025 SAP10.2 amendment which lowered gas unit prices ~13%; per ADR-0010 §3 only certs lodged ≥2025-07-01 are spec-comparable on cost-driven outputs. The e2e SAP ceiling is raised 3 → 6 and the cost-rel tolerance 0.10 → 0.15 with a docstring naming the drivers; tightens further when the Validation Cohort filter + Ecodesign/Appendix N adjustments land.
000474 also flagged as Vaillant ecoTEC pro PCDB-lodged; awaiting user's PCDB code lookup for that fixture.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
SAP 10.2 Appendix D2.1: when a cert lodges `main_heating_index_number` that resolves to a Table 105 (Gas/Oil Boilers) PCDB record, the PCDB winter seasonal efficiency overrides `seasonal_efficiency(...)` and the PCDB summer seasonal efficiency overrides the water heating Table 4a default (scalar — equation D1 monthly cascade deferred per Q5 grilling). Heat-network DLF override still wins where applicable.
Cert path: `main is not None and main.main_heating_index_number is not None and gas_oil_boiler_record(...)` is not None → use PCDB; otherwise fall back to the existing Table 4a/4b cascade. None of the 6 Elmhurst fixtures lodge a PCDB pointer, so their existing conformance is untouched.
Synthetic test pins the new precedence: a typical gas-combi cert with `main_heating_index_number=98` (verified Baxi 000098, winter eff 66.0%) produces `inputs.main_heating_efficiency == 0.66` instead of the 0.84 Table 4b code-102 default.
Golden corpus tolerance widened ±5 → ±7 SAP and ±25 → ±30 kWh/m² PE: two of the four PCDB-listed golden certs drift by ~1 SAP point / ~1.5 kWh/m² under the spec-faithful PCDB winter/summer override (the lodged assessor scores predate consistent PCDB use, so the gap widens for those two certs and stays under tolerance for the other two). All 343 tests pass.
Follow-up slices (named in SPEC_COVERAGE remaining work): equation D1 per-month water cascade, Appendix N heat-pump in-use factor + MCS / flow-temp adjustment via Table 362, FGHRS/WWHRS/HIU/storage-heater cert-side cascades via Tables 313/353/506/391.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds the cert-side lookup surface for Table 105: gas_oil_boiler_record(pcdb_id) -> Optional[GasOilBoilerRecord]. NDJSON is loaded once at module import, parsed into a by-pcdb-id dict, and cached by the Python runtime. Lookup is O(1).
Returns None when the cert's main_heating_index_number is not in Table 105 — caller falls back to the existing seasonal_efficiency(...) Table 4a/4b cascade.
Two tests pin the contract: verified Baxi 000098 lookup returns the typed record with brand "Baxi Heating", winter eff 66.0%, summer eff 56.0%; unknown PCDB ID returns None.
Slice 3 wires gas_oil_boiler_record into cert_to_inputs.main_heating_efficiency and water_efficiency precedence cascades per Q5=B (space heating + water heating scalar override).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Parser/ETL for BRE PCDB pcdb10.dat (April 2026 revision). domain.sap.tables.pcdb.parser exposes parse_table_105 (typed GasOilBoilerRecord with brand/model/winter+summer+comparative-HW efficiency/output kW/final year) plus parse_table_raw for generic positional ingestion (pcdb_id + raw row only). etl.py runs the full ETL: reads pcdb10.dat as latin-1, writes per-table .jsonl files under docs/sap-spec/. Idempotent; runnable via PYTHONPATH=packages/domain/src python -m domain.sap.tables.pcdb.etl.
Per Q1=D grilling: all 8 tables of interest ingested — 105 (Gas/Oil Boilers, typed) plus 122/143/313/353/362/391/506 (raw). Per-table typed refinement deferred to the follow-up slices that wire each table's cert-side cascade. Per Q3=B: typed fields decode against ncm-pcdb.org.uk ground-truth records (Baxi 000098 + Potterton 000619 + Saunier Duval 000732 verified by user); full raw row preserved on every record for forensics. Per Q2 user choice: NDJSON .jsonl format chosen over indented JSON to keep diff-friendliness while halving file size (17MB total vs 31MB pretty-printed).
Edge cases handled: latin-1 encoding (manufacturer addresses carry the degree sign), `'obsolete'` status string where a year would otherwise live, `'>70kW'` range indicator on output-power fields — non-numeric values fall to None with the raw string preserved on `raw`.
Slice 2 lands the domain.sap.tables.pcdb runtime lookup module (per-table by-pcdb-id dicts loaded at import time). Slice 3 wires Table 105 into cert_to_inputs.main_heating_efficiency / water_efficiency precedence cascades per Q5=B (space heating + water heating scalar override; equation D1 monthly + Appendix N HP factor + FGHRS/WWHRS/HIU deferred).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Path (i) — cert_to_inputs precompute. cert_to_inputs calls space_heating_fuel_monthly_kwh from local SpaceHeatingResult + Table 11 secondary fraction + per-system efficiencies; stashes the EnergyRequirementsResult on new `CalculatorInputs.energy_requirements` composite slot (default = _ZERO_ENERGY_REQUIREMENTS_RESULT).
_solve_month stops doing q/η inline — reads precomputed (211)m / (215)m fuel tuples directly via `inputs.energy_requirements.{main_1,secondary}_fuel_monthly_kwh[m-1]`. Existing `CalculatorInputs.main_heating_efficiency` / `.secondary_heating_efficiency` / `.secondary_heating_fraction` stay on the dataclass as inputs to the orchestrator (now redundant for the calculator's read path; kept for audit + backwards compat).
SapResult gains flat `main_2_heating_fuel_kwh_per_yr` and `space_cooling_fuel_kwh_per_yr` scalars — both zero in scope A, populated by future two-main + Table 10c SEER slices.
Round-trip test pins `inputs.energy_requirements.main_1_fuel_kwh_per_yr == result.main_heating_fuel_kwh_per_yr` to float equality (no rounding from the cert→inputs hop) and asserts scope-A scalars stay zero. PDF-derived ALL_FIXTURES pinning (Q5(α) grilling decision) blocked on PCDB integration — flagged in PCDB gap-list entry.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Spec line 7898: (109) = (98a) ÷ (4) + (108). New `worksheet/fabric_energy_efficiency.py` exposes a free function (no dataclass — single scalar output); `SpaceHeatingResult.space_heating_requirement_kwh_per_yr` (Σ(98a)) added so the spec literal — pre Appendix H solar offset — is the FEE input, not Σ(98c).
cert_to_inputs computes FEE from local SpaceHeatingResult + SpaceCoolingResult and passes via new `CalculatorInputs.fabric_energy_efficiency_kwh_per_m2_yr` (default 0.0 for backwards compat); calculator pass-through to `SapResult.fabric_energy_efficiency_kwh_per_m2_yr`. MonthlyEntry untouched — FEE has no per-month physics, only an annual scalar.
Six Elmhurst fixtures all (98b)=0 + (108)=0 → LINE_109 = LINE_99 exactly; ALL_FIXTURES asserts within 5e-3 tolerance (display-rounding floor inherited from LINE_98C_ANNUAL_KWH pins). Round-trip test asserts SapResult.fee equals space_heating_kwh_per_yr / TFA for the SAP10 minimal cert.
§11 compliance conditions (different ventilation / HW / lighting / gains column) are deferred — the FEE here is computed off rating-conditions inputs as a transparency output. Future §11 slice invokes the same function with §11-conditions upstream values.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Full §8 mirror per Q9 grilling: CalculatorInputs.space_cooling_monthly_kwh (default (0,)*12), MonthlyEntry.space_cool_requirement_kwh, SapResult.space_cooling_kwh_per_yr. _solve_month indexes into the cooling tuple and calculate_sap_from_inputs sums the per-month entries.
cert_to_inputs calls space_cooling_monthly_kwh with f_C=0 and cooling_gains=(0,)*12 — RdSAP convention since the cert never lodges cooled-area data and every `has_fixed_air_conditioning=False` cert collapses (107) to zero. The first cooling-enabled fixture needs a cooling_gains_from_cert helper + RdSAP cooled-area defaulting rule (deferred — SPEC_COVERAGE §8c row).
Round-trip test pins inputs.space_cooling_monthly_kwh = (0,)*12, result.space_cooling_kwh_per_yr = 0.0, and every MonthlyEntry.space_cool_requirement_kwh = 0.0 for a typical SAP10 minimal cert.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Shared SECTION_8C_ALL_ZERO_MONTHLY / SECTION_8C_ETA_LOSS_ALL_ONE / SECTION_8C_INTERMITTENCY_MONTHLY constants live in _elmhurst_fixtures.py; each of the 6 fixtures references them via plain attributes plus SECTION_8C_COOLED_AREA_FRACTION = 0.0 and the per-line LINE_103/106/107/108 + LINE_107_ANNUAL_KWH pins.
(100), (102), (104) values depend on H × (24−T_e) per fixture and are not pinned here — the algebra is exercised by the synthetic-positive leaf/orchestrator tests in slice 1. First cooling-enabled cert will need a fixture pinning those lines; deferred per Q10 grilling decision.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Tables 10a (η_loss with γ rounding to 8 dp + L=0 sentinel) and 10b (Q_cool with Jun-Aug inclusion mask + post-f_C × f_intermittent 1-kWh clamp per spec line 10321). Internal temperature hardcoded at 24 °C per Table 10a; intermittency factor scalar in / worksheet-shape tuple out.
Synthetic positive test (γ=1 closed-form branch) hand-computes the Jul-only 4.65 kWh end-to-end; synthetic zero test pins f_C=0 collapse. Leaf tested across all three γ-branches plus the rounding boundary and the L=0 sentinel.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds CalculatorInputs.space_heating_monthly_kwh (98c)m. _solve_month
indexes the field directly instead of calling monthly_heat_requirement_kwh
inline — q_heat now flows from the §8 orchestrator (including the
Table 9c step 10 summer clamp).
cert_to_inputs reuses the per-month HTC + total-gains tuples already
computed for §7 plus the MIT result, and calls space_heating_monthly_kwh
to populate the new field. Single codepath; mirrors §5/§6/§7 wiring.
Synthetic test fixtures (_baseline_inputs, _baseline_dwelling) compose
§7 → §8 in sequence so the BRE worked-example trace + calculator
sanity tests stay consistent with the spec-correct chain. Tests that
override calculator inputs at runtime (`test_zero_HTC`, `test_colder_
climate`) now recompute the upstream tuples instead of trusting a
calculator-internal recompute that no longer exists.
E2e SAP-score impact (000490): SAP shifted 57 → 60. The pre-§8 match
was fortuitous compensation — missing summer clamp's +1575 kWh/yr over-
prediction cancelled small under-predictions in §3/§5. Post-§8 the
residual upstream-precision gap surfaces (+2.5% space heating, +8.4% HW
fuel, −6.3% total cost, +3 SAP integer). Test updated to "within 3
points" with full delta breakdown documented — same pattern as the
000474 "within 7 points" test. Target stays SAP=57.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds LINE_95_M_USEFUL_GAINS_W, LINE_97_M_HEAT_LOSS_RATE_W,
LINE_98A_M_SPACE_HEATING_KWH, LINE_98C_M_TOTAL_SPACE_HEATING_KWH,
LINE_98C_ANNUAL_KWH, LINE_99_PER_M2_KWH to each
_elmhurst_worksheet_*.py fixture, plus an ALL_FIXTURES-parametrised
end-to-end test.
Tolerances vary by line ref per §5's per-line precedent:
- (95) η × G → 5e-2 W per month
- (97) H × ΔT → 5e-2 W per month
- (98a)/(98c) → 1e-1 kWh per month
- ∑(98c) annual → 1e-1 kWh
- (99) per-m² → 5e-3 kWh
Looser than §6/§7's flat 5e-3 W budget because §8 inputs (LINE_93,
LINE_94, LINE_84) carry 4-d.p. display rounding from upstream worksheets,
and §8's 0.024·31·(L−ηG) amplifies that rounding into the per-month kWh
band. The orchestrator computes in full precision; tolerances reflect
the fixture-pin precision floor, not physics error.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds the §8 orchestrator producing (95)..(99) line refs for all 12 months.
Composes the existing monthly_heat_requirement_kwh leaf with the spec
inclusion rule (Table 9c step 10 final clause):
"Include the heating requirement for each month from October to May
(disregarding June to September)"
Jun..Sep are zeroed regardless of computed value, on top of the per-month
value clamp (< 1 kWh / negative).
SpaceHeatingResult exposes (95) useful gains, (97) heat loss rate, (98a)
space heating requirement, (98b) solar space heating (always 0 — Appendix
H deferred), (98c) total, Σ(98c) annual + (99) per-m². All length-12
tuples + 2 scalars.
Driven by Elmhurst 000490 (98c) annual = 11183.2752 kWh to abs=5e-3 kWh.
Without the summer clamp the current calculator over-predicts annual by
+1575 kWh (+14%) on this fixture; the clamp closes the gap to spec.
Slice 3 wires CalculatorInputs.space_heating_monthly_kwh + cert_to_inputs;
calculator stops calling monthly_heat_requirement_kwh inline.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Removes:
- mean_internal_temperature_c (legacy single-η whole-dwelling fn)
- _zone_mean_temperature_c (only used by the deleted fn)
- calculator.py imports of mean_internal_temperature_c + utilisation_factor
(both unused since slice 4 removed the η-iteration loop)
- 2 obsolete tests asserting legacy single-η behaviour (coverage
subsumed by the §7 ALL_FIXTURES parametrised e2e at slice 3)
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds CalculatorInputs.mean_internal_temp_monthly_c (93)m and
CalculatorInputs.utilisation_factor_monthly (94)m. _solve_month indexes
directly into both — the 2-pass η fixed-point loop is gone (SAP10.2 §7
Table 9c is sequential, not iterative).
cert_to_inputs computes per-month HTC = transmission HLC + 0.33·V·(25)m,
sums (73)m + (83)m for total gains, and calls
mean_internal_temperature_monthly to populate both new fields. Single
codepath for all callers.
Synthetic test fixtures (_baseline_inputs, _baseline_dwelling) compute
their MIT + η via the §7 orchestrator too — preserves consistency with
the cert path while keeping the BRE worked-example trace asserting the
new spec-correct per-zone η values.
Atomic with cert_to_inputs (originally planned as slice 4 + slice 5):
introducing the calculator fields without populating them in cert_to_inputs
would break every cert-driven test. e2e SAP-score tests (000490 within 1
point, 000474 within 7 points) still pass with the new sequential η path.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds secondary_fraction (203) + secondary_responsiveness orchestrator
params. When both main systems heat the whole house (Table 9c case 1),
the u-formula consumes a weighted responsiveness:
R_eff = (1 - (203)) × R_primary + (203) × R_secondary
Synthetic equivalence test pins the contract: any (frac, R_primary,
R_secondary) call lands the same MIT as a single-main call with the
weighted R. No fixture exercises case 1 (all 6 Elmhurst = single combi),
so secondary_fraction defaults to 0 → identity behaviour.
Case 2 (different parts heated separately) deferred — needs (203) >
1-(91) branch + conditional T_2 averaging + per-system Table 4e
adjustment. No fixture data to drive.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds MeanInternalTemperatureResult + mean_internal_temperature_monthly,
implementing SAP10.2 §7 Table 9c steps 1-9 sequentially:
- (86) η_living = f(Ti = T_h1 = 21°C)
- (89) η_elsewhere = f(Ti = T_h2 from Table 9)
- (94) η_whole = f(Ti = (93)m adjusted MIT)
Three distinct η values per month, each computed from its own zone's Ti
via the existing utilisation_factor leaf. Closes the 6.6e-3 °C drift on
000490 (92)m Jan that the prior single-η implementation produced.
Driven by 000490 Jan worksheet (92)m = 15.1899 to abs=5e-3 °C. Other 11
months + per-zone line refs are exercised by the ALL_FIXTURES e2e test
in slice 3.
Legacy `mean_internal_temperature_c` retained (still used by calculator
_solve_month iteration); slice 4 deletes both when calculator wires the
new orchestrator's (93)m + (94)m fields.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Removes:
- calculator.WindowInput dataclass
- calculator.CalculatorInputs.windows field
- calculator._solar_gains_w function
- cert_to_inputs._window_inputs / _g_perpendicular / _frame_factor
- cert_to_inputs._G_PERPENDICULAR_BY_GLAZING_TYPE / _FRAME_FACTOR_BY_MATERIAL
/ _ORIENTATION_BY_CODE lookup tables (duplicated, spec-correct versions
live in solar_gains.py)
- 3 obsolete tests in test_cert_to_inputs.py that probed deleted internals;
one asserted the spec-incorrect Metal frame factor 0.83 (Table 6c spec
value is 0.8).
Test fixtures in test_calculator.py + test_bre_worked_examples.py pin the
prior synthetic solar 12-tuple verbatim so heat-balance numerics stay
identical pre/post §6 wiring.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
CalculatorInputs.solar_gains_monthly_w now flows from the §6 orchestrator
instead of the legacy per-month leaf. Roof windows + rooflights pass empty
because cert summaries (incl. Elmhurst) don't lodge them distinctly; the
§6 conformance test in test_solar_gains.py exercises the roof glazing path
via SECTION_6_ROOF_WINDOWS fixture overrides.
Behavioural delta vs legacy path: orchestrator's Table 6b uses 0.76 for
glazing codes 2 + 3 (spec-correct: "Double glazed, air or argon filled")
where _window_inputs hardcodes 0.72. Golden cert fixtures remain within
their ±5-SAP tolerance.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds the §6 (83)m output as a required 12-tuple field on CalculatorInputs;
_solve_month indexes into it directly instead of recomputing solar each
month via _solar_gains_w(windows, region, month).
Test (test_calculator_consumes_solar_gains_monthly_w_field_for_per_month_solar)
pins the read path: an explicit non-zero monthly tuple flows through
calculate_sap_from_inputs unchanged.
cert_to_inputs preserves identical behaviour during the migration by
computing the new field via the legacy _solar_gains_w leaf per month.
Slice 6 swaps that for solar_gains_from_cert; slice 7 deletes the legacy
leaf + WindowInput + windows field.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds SECTION_6_VERTICAL_WINDOWS, SECTION_6_ROOF_WINDOWS,
SECTION_6_ROOFLIGHTS, LINE_83_M_TOTAL_SOLAR_W, LINE_84_M_TOTAL_GAINS_W
to each of the 6 _elmhurst_worksheet_*.py fixtures, plus an
ALL_FIXTURES-parametrised end-to-end test in test_solar_gains.py.
144 assertions GREEN (12 months × 2 lines × 6 fixtures) at abs=5e-3 W:
- (83) total solar gains via solar_gains_from_cert
- (84) = §5 LINE_73_M_TOTAL_INTERNAL_GAINS_W + (83) — cross-checks
§5 conformance and §6 orchestrator in one go.
000516 exercises the roof window path (1.18 m² NE at 45° pitch, Z=1.0).
000474/000477/000487 carry mixed glazing types (g⊥=0.72 + g⊥=0.76 within
the same fixture) — verifies _g_perpendicular respects per-window
manufacturer-declared values.
`_build_section_6_epc(fixture)` is local to the test (handover §11):
fixture build_epc()s stay untouched. make_window gains a convenience
`solar_transmittance` shortcut so fixture literals stay readable.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Elmhurst lodges per-window g⊥ via Manufacturer-source
window_transmission_details.solar_transmittance on every window — the
Table 6b code lookup is the cascade fallback, not the primary path.
Without this the orchestrator picks Table 6b defaults that don't match
the worksheet (e.g. glazing_type=4 defaults to low-E soft 0.63, but the
manufacturer-declared value 0.76 is what the §6 row uses).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds RoofWindowInput + RooflightInput + SolarGainsResult dataclasses and
the solar_gains_from_cert orchestrator. Aggregates per-orientation sums
from epc.sap_windows (Table 6b/6c/6d lookups internal); roof windows take
explicit pitch (RdSAP10 Table 24 default 45°, Z=1.0) and rooflights are
horizontal per SAP10.2 §U3.2 p128 (pitch=0°, Z=1.0).
Driven by U985-0001-000490 worksheet (83) total solar gains 12-tuple to
abs=5e-3 W (audit reconciled the underlying flux + window-gain leaves to
≤5e-5 W; the 5e-3 W budget is the conformance ceiling for §6).
Table 6b g⊥ values are corrected vs cert_to_inputs._window_inputs (which
ships 0.72 for codes 2&3 — the spec is 0.76 for "Double glazed (air or
argon filled)"). The legacy lookup dies in slice 8 when _window_inputs
is deleted.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
z_solar_for_overshading() returns Table 6d first column (0.3/0.54/0.77/1.0).
Tracer for §6 — mirrors §5's _Z_L_BY_OVERSHADING pattern. Distinct from the
lighting Z_L (third column) used by §5 and the cooling Z (second column,
out of scope for SAP heating rating).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Table 6d note 2: roof windows / rooflights use Z_L = 1.0 regardless of
the overshading bucket applied to the rest of the dwelling's glazing.
Before this slice the orchestrator approximated rooflights as average
overshading (Z_L=0.83), driving 000516's (67) lighting 0.18 W (0.54%)
high. All wall windows in our 6-fixture corpus were correctly handled;
000516 is the only fixture with a lodged rooflight (the 1.18 m² NE
"window" showing Z=1.0 in the worksheet §6).
fixture | (67) max |err| before | after
--------+----------------------+--------
000516 | 0.1823 W (0.54%) | <0.005 W (<0.02%)
others | <0.0003 W | <0.0003 W
Changes:
- internal_gains_from_cert gains rooflight_total_area_m2 (default 0).
Rooflights summed at g_L=0.80 (Table 6b DG) × FF=0.7 (Table 6c PVC)
× Z_L=1.0 alongside wall windows (which still use the dwelling's
overshading-derived Z_L).
- SECTION_5_ROOFLIGHT_AREAS_M2 added to every fixture (empty tuple
except 000516 which carries (1.18,)).
- Tolerances on the §5 parametrised e2e test tightened from 2e-1 W
on (67) and 3e-1 W on (73) to 5e-3 W on both — every fixture now
closes to display rounding.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Removes the legacy SAP-10.3-flavoured scalar internal_gains_w API (plus
its InternalGainsBreakdown dataclass, _default_occupancy_sap_j, and the
L5b/L8c fallback constants used only by the legacy path). Calculator
now indexes a CalculatorInputs.internal_gains_monthly_w 12-tuple per
month instead of recomputing inline.
cert_to_inputs:
- _hot_water_fuel_kwh_per_yr now also returns the §4 (65)m
heat_gains_monthly_kwh tuple (was discarded). Plumbed forward into
internal_gains_from_cert via water_heating_gains bridge.
- Calls §5 orchestrator with EpcPropertyData + dwelling_volume_m3 +
(65)m + AVERAGE overshading (Table 6d default per note 1).
- Falls back to (0.0,) * 12 internal gains when TFA missing.
CalculatorInputs gains a new required field `internal_gains_monthly_w`.
Synthetic-input tests (test_calculator, test_bre_worked_examples)
updated to pass a 450 W constant tuple.
All 283 §1-§7 tests pass. E2e SAP-score regression unaffected for
000490 (still within 1 point) and 000474 (still within 7) because the
legacy fixture build_epc()s don't carry §5-specific sap_windows /
bulbs / heating-details, so the orchestrator returns the L5b lighting
fallback + zero (65)m — matches the legacy scalar's behaviour.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds SECTION_5_BULB_COUNT_LEL, SECTION_5_WINDOW_AREAS_M2,
SECTION_5_PUMP_AGE_STR and LINE_66..LINE_73 expected outputs to every
Elmhurst fixture (000474, 000477, 000480, 000487, 000490, 000516).
Constants extracted from the U985-0001-NNNNNN worksheets supplied
2026-05-20. All six fixtures share the same shape: all-LEL bulb
lighting, gas combi pump with unknown install date, average overshading.
Adds an ALL_FIXTURES-parametrized test in test_internal_gains.py that
composes a §5 EPC from the fixture's constants and drives
internal_gains_from_cert. Tolerances: ≤1e-3 W on the linear-in-N rows
(66/69/71), ≤2e-1 W on (67) lighting (worksheet-rounded N + rooflight
Z_L=1.0 approximated by AVERAGE Z_L=0.83), ≤5e-2 W on (68) appliances,
≤3e-1 W on (73) sum. Result: 26 tests pass; six fixtures conform to
≤0.6% lighting bias end-to-end.
The fixture's base build_epc() is unchanged — §5 EPC composition lives
in a test helper so the existing e2e SAP-score regression (000490, 000474)
remains pinned for the upcoming calc.py wiring slice.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Wires all §5 leaf functions into a single from_cert orchestrator that
chains (66) → (67) → (68) → (69) → (70) → (71) → (72) → (73) and
returns an InternalGainsResult. The caller provides §4 (65)m heat
gains (the only non-cert input) and overshading defaults to AVERAGE.
Cert derivations:
- Occupancy via Appendix J Table 1b from TFA
- Lighting: RdSAP §12-1 per-lamp-type bulb defaults aggregated to
C_L,fixed + ε_fixed; C_daylight via L2a from sap_windows × Z_L
from Table 6d. L5b + L8c fallbacks when no bulb/window data lodged.
- Pumps/fans: maps central_heating_pump_age_str on the first
MainHeatingDetail to PumpDateCategory. Liquid-fuel / warm-air / PIV
/ MV / HIU branches deferred (reachable via leaf fns; currently
return 0 in the orchestrator for the combi-gas-natural-vent
population that covers all 6 Elmhurst fixtures).
Slice 9 tracer test hand-builds a 000490-lookalike EPC rather than
mutating `_elmhurst_worksheet_000490.build_epc()` — keeps the existing
e2e SAP-score regression test pinned. Slice 10 will extend the fixture
proper and parametrize over ALL_FIXTURES.
Also: extends make_minimal_sap10_epc with low_energy_fixed_lighting_bulbs_count
since the existing builder only exposed CFL/LED/incandescent separately.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Closes the §5 leaf-function surface:
- total_internal_gains_monthly_w sums (66) + (67) + (68) + (69)
+ (70) + (71) + (72) element-wise. (71) carries negative sign so the
losses term subtracts.
- InternalGainsResult frozen dataclass bundles all 7 line refs plus the
total as 12-tuples — the typed payload returned by the orchestrator.
Verified against Elmhurst U985-0001-000490 (73)m to ≤1e-2 W/month.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Implements Table 5a row-by-row leaf functions:
central_heating_pump_w pump install-date bucket (3/7/10 W)
liquid_fuel_boiler_pump_w 10 W when oil-fuel pump inside dwelling
liquid_fuel_warm_air_pump_w 10 W for liquid-fuel warm-air systems
warm_air_heating_fan_w SFP × 0.04 × V (heating-season)
piv_fan_w IUF × SFP × 0.12 × V (year-round)
balanced_mv_no_hr_fan_w IUF × SFP × 0.06 × V (year-round)
heat_interface_unit_w PCDB kWh/day × 1000 / 24 (year-round)
Plus pumps_fans_monthly_w(heating_season_w, year_round_w) which applies
the Table 5a footnote-a seasonal mask (Jun-Sep = 0 W heating-season
contribution per Elmhurst worksheet convention).
PumpDateCategory enum maps from EpcPropertyData.central_heating_pump_age_str
("Pre 2013" / "Post 2013" / "Unknown" / etc.) at the orchestrator layer.
MVHR and MEV systems intentionally have no leaf fn — gains are zero per
Table 5a notes (MVHR effect is in MVHR efficiency; MEV simply omitted).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Implements the full SAP10.2 Appendix L lighting calculation: Λ_B (L1)
→ Λ_req (L3) → Λ_prov (L6) → Λ_topup (L7) → E_L,fixed/topup/portable
(L9a-d) → monthly cosine modulation (L10) → 0.85 × 1000 / (24 × n_m)
heat-gain bridge (L12).
Critical detail uncovered while reconciling against the 000490
worksheet: C_daylight uses Z_L from Table 6d's **third column** (light
access factor), NOT the 0.77 first column used for §6 solar gains. For
"Average" overshading Z_L = 0.83. Conflating the two columns gives a
~2% lighting-energy bias.
Verified against Elmhurst U985-0001-000490 (67)m to ≤5e-3 W/month
(0.14% on E_L) using worksheet bulb table (8 LEL × 80 lm/W × 15 W)
and Table 6b/6c/6d defaults for the window inputs.
The orchestrator slice will derive C_L,fixed + ε_fixed from RdSAP §12-1
per-lamp-type defaults (LED 100 lm/W, CFL 55 lm/W, LEL 80 lm/W,
incandescent 11.2 lm/W) and C_daylight from the cert's window data.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Pure unit conversion: G_WH,m = 1000 × (65)m / (n_m × 24). The §4
heat_gains_from_water_heating_monthly_kwh output already encodes the
25%/80% spec-recovery factors for delivered-heat vs pipe-side losses;
this bridge just lands the kWh/month into watts for the §5 sum.
Verified against Elmhurst U985-0001-000490 (72)m row — exact to 4 d.p.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
