The Appendix N3.7 water-heating 100% floor drops corpus MAE 0.726 -> 0.721
and lifts within-0.5 74.1% -> 74.2% on the 1000-cert RdSAP-21.0.1 sample
(cert 100110101713 moves inside +-0.5). Tighten the MAE ceiling to 0.722 and
the within-0.5 floor to 0.742, and log the slice.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The heat-pump PSR-extension fix (SAP 10.2 Appendix N2) drops corpus MAE from
0.740 to 0.726 on the 1000-cert RdSAP-21.0.1 sample; within-0.5 holds at
74.1%. Tighten the ceiling and log the slice.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
within-0.5 floor 0.73->0.74 (now 0.741), MAE ceiling 0.762->0.740 (now
0.7397) on the fixed RdSAP-21.0.1 corpus. Log entry appended.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
A gov-API flat can lodge dwelling_type="Mid-floor flat" while carrying its
own exposed roof — a top-floor flat mislabelled mid-floor. _dwelling_exposure
keyed roof exposure on the dwelling_type label alone, dropping the roof
heat-loss term: space-heating demand under-read ~32%, SAP over-read +7.
Fix: when the main building part lodges a *determined* roof_insulation_location
(an RdSAP integer code, not the "ND" Not-Defined party-ceiling sentinel),
expose the roof regardless of a contradictory label. Structured field, not a
description string and not roof_construction (which the gov-API lodges
building-wide on every unit, so it is not a per-unit signal).
On the RdSAP-21.0.1 corpus roof_insulation_location separates the classes with
zero disagreement: all 190 party-ceiling flats lodge "ND"; the 4 mid/ground
flats this exposes all move toward lodged, 0 away. within-0.5 73.3% -> 73.6%,
MAE 0.774 -> 0.761 (ratchets tightened). Verified end-to-end on the same
block: 715363 (location 6, RHI 2694) 81 -> 74 = lodged; genuine mid-floor
sibling 715395 (location ND, RHI 1024) stays party at 83 = lodged.
The override is additive (only ever exposes a label-dropped roof) and reads
the main part, so multi-part flats with a party main ceiling stay party.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Route the Google Solar client through the shared call_with_retry with
full jitter (de-synchronises the 32 concurrent containers per Google's
"avoid synchronised requests" guidance), honouring Retry-After, a 60s max
backoff (rides out the 600 QPM per-minute window), and 6 bounded retries.
429/5xx/transport errors are transient; other 4xx propagate immediately;
404-entity-not-found stays BuildingInsightsNotFoundError. On exhaustion a
TransientHttpError surfaces so the subtask fails and is re-triggered (no
silent degrade).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
SAP 10.2 Table 3a (PDF p.160) additional combi loss (61)m. Two coupled
defects, both surfaced by simulated case 49 (000565 + gas combi, U985
"Combi keep hot type = None") sitting at SAP 71.43 vs the worksheet's 72:
1. The cascade defaulted EVERY non-PCDB combi to the flat keep-hot
time-clock row (600 × n/365). A combi WITHOUT a keep-hot facility uses
row 1 (600 × fu × n/365, fu = V_d/100 when daily HW < 100 L/day) —
over-counting (61)m for the no-keep-hot cohort. `water_heating_from_
cert` now defaults to the "without keep-hot" row.
2. `pcdb_combi_loss_override` returned None for keep_hot_facility=1/
timer=1, leaning on the OLD flat-600 default. So flipping the default
silently turned 190 corpus PCDB keep-hot-time-clock combis into
no-keep-hot. Fixed to return the flat keep-hot row EXPLICITLY.
Key insight (the Summary is the input echo; the U985 keep-hot line is a
computed OUTPUT, so it must be derivable): keep-hot rides on the PCDB
boiler record (Table 105 keep_hot_facility/timer), resolved by
`pcdb_combi_loss_override`. A generic SAP-code combi with no PCDB record
(case 49, PCDF ref 0) has no keep-hot by construction → row 1. So the
default is not a guess — it is the spec-correct value for non-PCDB combis.
Worksheet-proven: case 49 → cost £726.696, SAP 72 — matching the
accredited worksheet to the digit (continuous 71.6945 = the worksheet's
own 71.6945). 000516 (keep-hot None) also exact (£860.716, SAP 63);
000490 (PCDB 10328, keep_hot_facility=1/timer=1) keeps its flat-600 via
the PCDB path. Masked until now because every prior combi-loss worksheet
fixture was keep-hot (000490/000474/000480 time-clock) or had V_d >= 100
every month (001431, rows coincide); case 49 is the first no-keep-hot one.
Corpus within-0.5 72.7% -> 73.3%, MAE 0.781 -> 0.774, PE 3.5 -> 3.4;
ratcheted _MAX_SAP_MAE 0.785 -> 0.775, _MAX_PE_PER_M2_MAE 3.6 -> 3.5.
Note: pyright strict type gate not run locally (pyright not installed).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Extends the dMEV intermittent-fan fix (4db05e84) to MVHR. A balanced
whole-house MVHR system IS the dwelling's ventilation, so the lodged (7a)
intermittent-extract-fan count is explicit — a lodged 0 means 0, not the
RdSAP 10 Table 5 age-band "unknown" default. The cascade was substituting
the default (here 20 m³/h) into worksheet line (8) openings, inflating
(16/18) infiltration → (21) → (22b) → (25) effective ach → (38)
ventilation heat loss → the space-heating demand.
Worksheet-proven on simulated case 49 (000565 + Vent Axia 500140 MVHR,
lodged (7a)=0): our (8) openings 0.0723 -> 0.0000, (18) 0.7223 -> 0.6500,
(25)m Jan 0.9423 -> 0.8571, all now matching Elmhurst exactly; space-
heating demand 7857 -> 7528 kWh (worksheet 7546). SAP 70.90 -> 71.43
continuous. (The residual to the worksheet's 72 is its own continuous SAP
71.69 rounding up, driven by a separate gas-combi water-heating-loss gap,
not ventilation.)
Scoped to EXTRACT_OR_PIV_OUTSIDE + MVHR only — MV-without-HR
(mechanical_ventilation=1) stays on the default-substitution path
(forcing its lodged 0 regressed 47 Howsman / 18 Jutland and is not
worksheet-validated). Corpus within-0.5 holds 72.7%, MAE 0.782 -> 0.781.
Note: pyright strict type gate not run locally (pyright not installed).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
MVHR (24a) heat-recovery support, part 2: the mapper + cascade wiring.
Both source paths now resolve balanced whole-house MV with heat recovery
to the MVHR kind:
- gov-API: `_API_MECHANICAL_VENTILATION_TO_KIND` 4 → "MVHR" (was None /
treated as natural — under-stated ventilation heat loss, over-rating).
- Elmhurst Summary: `_ELMHURST_MV_TYPE_TO_KIND` "Mechanical ventilation
with heat recovery (MVHR)" → "MVHR" (was UnmappedElmhurstLabel, which
blocked the whole Summary for MVHR dwellings).
cert_to_inputs resolves the in-use heat-recovery efficiency + SFP for an
MVHR cert (`_mvhr_system_values`): pick the PCDB Table 323 data point by
the lodged wet-room count (SAP 10.2 §2.6.4), multiply the raw efficiency
by the Table 329 ducts-inside-envelope in-use factor (0.90) and the raw
SFP by the per-duct-type factor (rigid 1.4), and feed:
- the §2.6.6 eq (2) effective-air-change credit (23c) → (24a)/(25)m;
- the (230a) fan electricity (in-use SFP × 1.22 × V), costed but NOT
added to the Table 5a gains (its effect is in the efficiency).
An MVHR lodged with no PCDF index falls back to the SAP 10.2 Table 4g
default (raw efficiency 66% × 0.70, raw SFP 2.0 × 2.5).
Worksheet-proven on simulated case 49 (000565 semi + Vent Axia Sentinel
Kinetic B 500140 + gas combi → Elmhurst Current SAP 72): every MVHR line
matches Elmhurst exactly — (33) fabric heat loss 100.5923, (23c) in-use
efficiency 81.9% = 91 × 0.90, (25)m Jan 0.8571, (230a) fan electricity
415.9325, (231) total pumps/fans 501.9325. The residual SAP 71 vs 72 is
the known 000565-family space-heating-demand artifact (same -1/-2 seen on
cases 47/48), not the MVHR logic.
Corpus: within-0.5 72.6% -> 72.7%, MAE 0.788 -> 0.782, PE 3.6 -> 3.5.
The 3 gov-API MVHR certs: Flat 1 +6 -> 0 (Table 4g default path) and
12a Princes Gate +3 -> +1 (heat-recovery credit); Apartment 707 -4 -> -6
is a separate baseline under-rate (it under-rated as natural too — the
MVHR credit correctly adds ventilation loss per Elmhurst's method).
Ratcheted _MAX_SAP_MAE 0.79 -> 0.785, _MAX_PE_PER_M2_MAE 3.7 -> 3.6.
Note: pyright strict type gate not run locally (pyright not installed).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Closes out the cohort-broadening work with its decision record and consolidates
the retry plumbing.
ADR-0034 documents broadening the EPC-Prediction cohort to the real unit
postcodes nearest the target (via postcodes.io) when its own postcode holds no
same-type comparable — extending ADR-0031 decision 5. Records why postcodes.io
was chosen over council[] (whole-LA, no property_type in rows), a bulk Code-Point
Open / ONSPD dataset, and the OS Places radius API, and the lazy / nearest-first
early-stop / soft-fail policy. Broadening-specific docstrings now cite 0034.
Retry consolidation: extract the EPC client's call_with_retry into a shared
infrastructure/http_retry.py keyed off a generic TransientHttpError marker, so
the mechanism (exponential backoff, Retry-After) is shared while each client
keeps its own transient policy. EpcRateLimitError now subclasses TransientHttpError
(still an EpcApiError); PostcodesIoClient routes through the same helper, raising
TransientHttpError on 429/5xx and soft-failing to the seed once exhausted (the EPC
client propagates instead). Direct tests for the shared helper; EPC + postcodes.io
suites repointed at the shared sleep.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Two reconciliations to make the modelling_e2e Lambda handler production-ready.
1. Price through the off-catalogue overlay, drop the workarounds
The handler priced through a plain ProductPostgresRepository and excluded
secondary_heating_removal / system_tune_up / system_tune_up_zoned to dodge
ProductNotFound (and a poisoning pgEnum DataError). Those measures are now
priced by catalogue_with_off_catalogue_overrides (already used by the e2e
runner and PostgresUnitOfWork), so the exclusions are removed and ALL measure
types are considered. This also fixes gas-boiler / single-glazed properties,
which Dan's handler never excluded and so still crashed (the standard
system_tune_up option is built unconditionally — the considered-measures
exclusion never actually gated it).
2. Broaden the EPC-Prediction cohort to nearby real postcodes (ADR-0031)
A property with no lodged EPC and no same-type comparable in its own postcode
(e.g. the only flat among houses) used to gate out and fail the subtask. The
gov EPC API cannot search by radius/outcode, so we resolve the real unit
postcodes physically nearest the target via postcodes.io (keyless; already a
trusted in-repo dependency) and walk them nearest-first until enough same-type
comparables surface. New PostcodesIoClient (transient-failure retry with
exponential backoff, soft-failing to the seed so broadening never breaks
prediction) and EpcComparablePropertiesRepository.candidates_near. Wired into
the handler and e2e runner; broadening is lazy (only on gate-out) and memoised
per (postcode, property_type).
Validated live: property 728476 (gas boiler) prices system_tune_up at GBP295;
property 718580 (lone flat in BR6 6BS) now predicts via nearby BR6 postcodes.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Chasing the space-heating demand gap on "simulated case 48" (main 691 + Unknown
meter + 903 dual immersion): our SAP 55 vs Elmhurst 57. Every §10a cost line
already matched to the penny; the residual was demand — our space-heating
energy 3849.8 kWh vs Elmhurst 3513.8 (+9.6%). Traced through the worksheet: our
ventilation heat loss (38) ran ~35.5 W/K vs Elmhurst 27.76 — we were adding 20
m3/h of intermittent extract fans (the Table 5 age-band default) on a dwelling
with a decentralised mechanical extract (dMEV) system that lodges 0 fans.
SAP 10.2 §2 (PDF p.13): a whole-house mechanical EXTRACT system provides
extraction via the (23a) 0.5 system air-change rate; the lodged intermittent
extract-fan count (7a) is then explicit — a lodged 0 means 0 (the dMEV is the
ventilation), NOT "unknown". The Table 5 default is an unknown-fallback for
NATURALLY ventilated dwellings only, so it must not be substituted here.
Fix: for EXTRACT_OR_PIV_OUTSIDE, take vc.intermittent_fans as-is (no age-band
default). Worksheet-proven on two dMEV builds of cert 000565: "case 48" lodges
(7a)=0 -> our SAP 55 -> 57 EXACT; the original 000565 fixture lodges (7a)=2 and
keeps 2 (its e2e pins are unchanged). An earlier draft that forced fans=0 broke
000565 (which legitimately has 2) — corrected to "lodged as-is".
within-0.5 72.5% -> 72.6%, MAE 0.789 -> 0.788; CO2/PE unchanged. The fix also
reduces a systematic under-rating bias in the 21-cert dMEV cohort (median dSAP
-0.22 -> -0.08). Scoped to EXTRACT_OR_PIV_OUTSIDE; balanced MVHR/MV kinds left
untouched pending their own worksheet. SAP-schema regression
test_18_0_0 pin 80 -> 81 (closer to its lodged 84, same cause). Spec-pinned in
test_cert_to_inputs (dMEV-lodged-0 vs natural-default). pyright not installed
in this container -- strict type gate not run locally.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
MAE improved 0.793 -> 0.789 via the Unknown-meter + dual-electric-immersion
off-peak trigger (commit 22fe4f41). Ratchet the ceiling so the gain can't
silently regress. within-0.5 unchanged (72.5%).
pyright not installed in this container — strict type gate not run locally.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Main heating system 2's space-heating fuel cost (worksheet (213)) was billed
at main system 1's Table 32 unit price (`main_2_high_rate_gbp_per_kwh` reused
`main_1_high_rate_gbp_per_kwh`). For a dual-FUEL pair this grossly mis-costs the
second main: cert 10032957680 "Copse Cottage" (main 1 electric room heaters
fuel 30, main 2 wood logs fuel 6) charged its 9481 kWh of wood at 13.19 p/kWh
instead of 4.23 p/kWh — +£850/yr → SAP 21.75 vs lodged 45.
Route main 2 through its own fuel code (`_main_fuel_code(details[1])`), mirroring
the existing secondary-fuel handling. Copse Cottage 21.75 -> 45.94. Corpus
within-0.5 holds 72.5%, SAP MAE 0.815 -> 0.793 (ratcheted ceiling 0.82 -> 0.80);
CO2/PE unchanged. Same-fuel dual mains (gas+gas) unaffected. Off-peak-tariff
dual-fuel mains still defer to the legacy scalar path (separate slice).
Spec-cited unit pin added (AAA). pyright not installed locally — strict type
gate not run.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Table 5 reads "Number of extract fans if known; if number is unknown:
[age-band default]" — the default is an UNKNOWN-fallback, NOT a floor. The
cascade applied `max(lodged, table_5_default)`, flooring a genuinely-lodged
count up to the age-band minimum: e.g. an age H-M dwelling lodging 2 extract
fans was billed at the 6-8-room default of 3, over-counting ventilation line
(8) and the heat-loss coefficient. Fixed to `lodged if lodged > 0 else
default` (a lodged 0 is the Elmhurst/RdSAP "unknown" form → default; any
positive count is taken literally).
Surfaced by Khalim's Elmhurst stress worksheet (simulated case 46): this was
its last ventilation residual — our Jan effective ACH 9.14 -> 9.0748 (exact
match to the accredited worksheet), SAP 29 -> 30 = Elmhurst, cost £1496 vs
£1493. Corpus IMPROVED: within-0.5 71.6% -> 72.5%, MAE 0.819 -> 0.815 (the
max-flooring over-counted ventilation on every cert lodging fans below its
age default). Floor ratcheted 0.71 -> 0.72. pyright not installed locally.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The corrected stone branch (age-E-only cap, §3.5 Table-3 unknown-thickness
default, Scotland band-J override) improved the corpus gauge to SAP MAE 0.819
and PE MAE 3.6 kWh/m2/yr. Lock the gains in and record the corrected
mechanism in the provenance log; within-0.5 (71.6%) and CO2 (0.08) unchanged.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
An uninsulated stone wall of lodged thickness, age bands A-E, is billed by
the RdSAP 10 §5.6 Table-12 formula on its measured thickness — sandstone /
limestone U = 54.876·W^-0.561, granite / whinstone U = 45.315·W^-0.513. Two
bugs suppressed it:
1. CAP: the as-built branch capped the formula result at the Table-6
typical-thickness default (`if u0 >= 1.7: return 1.7`). But the formula
only dips below 1.7 past ~488 mm (sandstone) / ~640 mm (granite), so the
cap nullified §5.6 for essentially every real-thickness stone wall,
under-counting fabric loss and over-rating. A measured 400 mm sandstone
age-B wall is 1.90 (Elmhurst-confirmed), not 1.70.
2. NO INSULATION-STATE GATE: the branch fired for any stone wall with a
lodged thickness, including ones whose insulation is "Unknown". RdSAP
treats an unknown-insulation wall via the Table-6 typical-thickness
default, NOT as bare stone of the lodged thickness — so a 50 mm granite
wall with Unknown insulation must read 1.70 (worksheet), not the formula's
6.09. Gated on `wall_insulation_type is not None`.
Fixes the 2 long-standing stone-U unit tests (granite 120 mm → 3.8871,
sandstone 120 mm → 3.7408 — they were correct red tests, not "known fails").
Corpus within-0.5 70.3% -> 71.6% (MAE 0.833 -> 0.822); ratcheted floors to
0.71 / 0.83. Worksheet fixture 000565 (granite 50 mm Unknown → 1.70) still
passes via the insulation gate. The two stone groups (sandstone/limestone vs
granite/whinstone) keep their distinct §5.6 coefficients.
pyright not installed in this codespace (strict gate not run locally).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The SAP rating is spec-floored at 1 ("if the result of the calculation is
less than 1, the rating is 1"). `sap_rating_integer` already clamps, but the
continuous `sap_score_continuous` did not — so a degenerate dwelling could
emit a physically impossible negative SAP. Apply the same max(1, …) floor to
the continuous value (the un-rounded part is for sensitivity near real
ratings, not for negative ratings).
Removes a -12.3 accuracy outlier on the committed corpus (cert 422000111926,
lodged at the floor of 1, was computing -11.3): within-0.5 70.2% -> 70.3%,
MAE 0.845 -> 0.833. Ratcheted the corpus MAE ceiling to 0.84. Unit-pinned in
test_calculator.
pyright not installed in this codespace (strict gate not run locally).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The gov-API lodges secondary fuel as an enum whose value can COLLIDE with a
different same-valued RdSAP 10 Table 32 / SAP 10.2 Table 12 fuel code:
- enum 9 = "dual fuel (mineral and wood)" vs Table code 9 = LPG SC11F
- enum 5 = "anthracite" vs Table code 5 = LPG (bulk)
The main-fuel boundary already canonicalises these (`_GOV_API_COLLISION_
FUELS`), but the SECONDARY-heating cost + CO2/PE paths never did — they took
the bare same-value lookup, so a dual-fuel room heater was priced as LPG
(3.48 vs dual-fuel 3.99 p/kWh) and emitted as LPG (CO2 0.241 vs 0.087),
and an anthracite secondary as bulk LPG (12.19 vs 3.64 p/kWh). The price
under-count over-rates SAP; the CO2 over-count inflates emissions.
Fix: add enum 9 to `_GOV_API_COLLISION_FUELS` (5 and 33 were already there)
and canonicalise the secondary fuel code on both the cost
(`_secondary_fuel_cost_gbp_per_kwh`) and factor (`_secondary_fuel_code`)
paths, mirroring the main-fuel boundary. canonical_fuel_code only touches
{5,9,33}, so genuinely Table-coded secondaries (House coal 11, wood logs 20,
community fuels 30-32) are left unchanged — confirmed by a full-map audit.
Corpus: within-0.5 69.7% -> 70.2% (MAE 0.854 -> 0.845; dual-fuel-secondary
cohort 42.9% -> 49.0%, signed +0.55 -> +0.41) and CO2 MAE 0.12 -> 0.08 t/yr
(bias +0.04 -> 0.00). Ratcheted the corpus floors (within 0.70, MAE 0.85,
CO2 0.09, PE 4.0). A prior session deferred enum 9 ("direction not
understood") while the EPC PE/CO2 lens was confounded by the climate-cascade
bug (fc7c4d2d); on the corrected lens the over-rate direction is clear.
pyright not installed in this codespace (strict gate not run locally).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The SAP/EI rating is computed on UK-average weather (Appendix U Tables
U1-U3 region 0) so ratings are nationally comparable, but Appendix U
paragraph 1 (PDF p.124) requires that "other calculations (such as for
energy use and costs on EPCs) are done using local weather. Weather data
for each postcode district are taken from the PCDB". `Sap10Calculator.
calculate` ran ONE cascade (UK-average) and fed it to SAP, CO2 AND primary
energy, so every cert's EPC-displayed CO2/PE were computed on the wrong
climate. Because most of England is warmer than the UK-average, this
systematically OVER-counted heating demand on the emissions/PE outputs.
The two cascades (`cert_to_inputs` rating, `cert_to_demand_inputs`
postcode) already existed; this wires the demand cascade into the
production entry point and grafts its CO2/PE onto the rating result (SAP
unchanged). The corpus gauge's longstanding +5% CO2/PE over-estimate was
mostly this climate bug, NOT (as previously diagnosed) per-cert mapper
fidelity:
CO2 MAE 0.26 -> 0.12 t/yr (bias +0.18 -> +0.04)
PE MAE 13.6 -> 3.8 kWh/m2 (bias +9.0 -> +0.24)
SAP within-0.5 = 69.7% (rating cascade, unchanged)
Worksheet-validated to 1e-4 on simulated case 45 (heat-pump ground-floor
flat, postcode W6): the P960 prints the current dwelling twice — Block 1
on UK-average weather (SAP 60.5318, CO2 692.13) and Block 2 on postcode
weather (CO2 626.78, PE 6581.59). Both reproduce exactly. Added a tracked
case-45 Summary fixture + two-cascade cascade pin as a permanent guard,
and ratcheted the corpus CO2/PE ceilings to 0.13 / 4.2. The e2e Elmhurst
suite (Block-1 line refs) now pins the rating cascade directly; the two
Vaillant overlay snapshots refreshed to demand-cascade CO2/PE.
pyright not installed in this codespace (strict gate not run locally);
change is type-trivial (dataclasses.replace over SapResult).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The flat floor-exposure heuristic keys on dwelling_type: a flat defaults
to has_exposed_floor=False (assuming a heated dwelling below). The
Elmhurst Summary path lodges a ground-floor flat's vertical position as a
"Ground floor" floor_type rather than the API floor_heat_loss=1 exposed
code, and the mapper can label such a flat "Top-floor flat" — so the
cascade dropped the ground floor entirely (a ground floor is in contact
with the ground and carries heat loss).
Treat a "ground floor" floor_type as a heat-loss floor, overriding the
dwelling-level suppression upward — mirroring the existing "another
dwelling below" party override downward.
Worksheet-validated to 1e-4 on simulated case 45 (a ground-floor flat
the mapper labelled "Top-floor flat"): floor (28a) 0 -> 25.38 W/K,
fabric (33) 75.63 -> 101.0104, HTC (39) 112.93 -> 145.3579, all matching
the P960 exactly; SAP 67.81 -> 62.52. RdSAP-21.0.1 corpus within-0.5
69.5% -> 69.7% (MAE 0.859 -> 0.854). Floors ratcheted. Pinned in
test_heat_transmission (ground-floor billed + party-floor suppressed).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The deduplicated `epc.roofs[]` list cannot be indexed 1:1 against the
building parts (190/329 multi-part certs have len(roofs) != len(parts)),
so every part's `u_roof` consumed a SINGLE join of all roof descriptions.
That leaked one part's insulation state onto another: a "Flat, no
insulation" extension dragged a "Pitched, insulated (assumed)" main roof
to the uninsulated 2.30, ~3x over-stating its heat loss. 3-part certs
systematically under-rated (56% within-0.5, mean -0.79 SAP).
Partition the non-RR roof descriptions into flat vs pitched/sloping and
match each part to its own kind (`_main_roof_descriptions_by_kind`),
falling back to the global join when a part's kind has no matching entry.
Corpus cert 100010129331: roof 110.5 -> 31.3 W/K, +13.10 -> -0.05 SAP.
RdSAP-21.0.1 within-0.5 68.8% -> 69.5% (MAE 0.888 -> 0.859; PE 13.9 ->
13.6); 3-part cohort 56% -> 61%. Floors/ceilings ratcheted. Pinned in
test_heat_transmission (by_kind split + mixed-roof no-contamination).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The §5.8 Table-14 added-insulation R-value adjustment was gated to
WALL_SOLID_BRICK, so a stone (granite/sandstone) wall lodging
wall_insulation_type 1/3 ("External"/"Internal") + a thickness fell
through the §5.6 thin-wall branch and was billed at its UNINSULATED U
(e.g. sandstone 520 mm + 100 mm internal: 1.64 instead of 0.30 → ~5×
the wall heat loss). Mirror the brick insulation branch into the stone
block, feeding the RAW §5.6 U₀ into the §5.8 chain per the same rule the
brick branch and the dry-lined granite pin 000565 already follow (the
Table-6 footnote (a) 1.7 cap does not apply on the insulated path).
Corpus cert 100052159386 (sandstone 520 mm + 100 mm internal): -26.20 ->
-4.08 SAP, walls 300 -> 55 W/K. RdSAP-21.0.1 corpus within-0.5 68.6% ->
68.8% (SAP MAE 0.942 -> 0.888; PE MAE 14.3 -> 13.9; CO2 0.27 -> 0.26);
floors/ceilings ratcheted. Unit-pinned in test_rdsap_uvalues.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The gov API lodges a NON-SEPARATED conservatory (conservatory_type=4) as a
glazed "building part" carrying only {floor_area, room_height,
double_glazed, glazed_perimeter} — no fabric, no floor dimensions. The
four fields were undeclared on the 21.0.1 SapBuildingPart, so `from_dict`
dropped them and the conservatory was silently lost: it billed no §6.1
window/rooflight/floor and added nothing to TFA (5 corpus certs over-rated
— too little heat loss → SAP too high).
Fix (21.0.1 schema + mapper):
- declare the four glazed fields on `SapBuildingPart`;
- `_api_sap_conservatory` builds `EpcPropertyData.sap_conservatory` from
the glazed BP (identified by a lodged `glazed_perimeter`; only type-4
conservatories lodge it — separated ones, §6.2, lodge nothing);
- exclude the glazed BP from the fabric building-part loop (it is billed
by the §6.1 cascade, not as a dwelling part);
- `_total_floor_area_from_building_parts` adds the conservatory floor area
to TFA (drives occupancy → §4/§5 demand).
Validation is cross-mapper parity, NOT a corpus back-solve: the API mapper
feeds the SAME worksheet-validated §6.1 cascade (`conservatory_geometry`,
pinned to 1e-4 against the case-44 Summary) as the Elmhurst path — so the
API conservatory fabric is correct by construction. `from_api_response`
on an injected type-4 cert reproduces the glazed wall (perimeter × ground-
floor room height = 22.05), glazed roof (floor/cos20 = 12.77) and Table 25
double U_eff (2.758 wall / 2.993 roof); a separated (type 2/3) cert lodges
no glazed BP → disregarded per §6.2.
Gauges: corpus within-0.5 67.9% → 68.6% (MAE 0.959 → 0.942; floor 0.67→0.68,
ceiling 0.97→0.95); /tmp eval mean|err| 0.822 → 0.817. Harness 47/47
0-raised; regression = the 3 pre-existing fails; pyright net-zero (65=65).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Lock in the detailed-RR slope + stud-wall gain (corpus within-0.5
67.3% -> 67.5%, MAE 1.020 -> 0.987). The corpus is a fixed 1000-cert
deterministic gauge, so the thresholds track measured HEAD with a small
margin per the ratchet convention.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Roofs lodged insulated at rafters carry their thickness in a DEDICATED
gov-EPC API field, `rafter_insulation_thickness` (e.g. "225mm"), while
`roof_insulation_thickness` stays None (rafters aren't loft joists). That
field was undeclared on the 21.0.x schemas, so `from_dict` silently
dropped it — the rafter certs only *looked* redacted (roof EER 2-4 =
insulated, yet no thickness), and the cascade fell to the Table 18 col (2)
unknown default (2.30), badly under-rating them.
- declare `rafter_insulation_thickness` on RdSapSchema21_0_0/21_0_1 +
EpcPropertyData.SapBuildingPart (mirrors the existing
sloping_ceiling_/flat_roof_insulation_thickness dropped-field handling).
- thread it through `from_rdsap_schema_21_0_0/21_0_1` (older schemas get
None via getattr).
- `heat_transmission` prefers `rafter_insulation_thickness` over
`roof_insulation_thickness` when the part is at-rafters, so the measured
RdSAP 10 §5.11.2 Table 16 column (2) row applies (225 mm → 0.25).
Completes the rafters roof fix: with the real thickness read, the rafter
certs are recovered rather than over-stated — cert 3100-8675-0922-8628
(band E, rafters 225mm) +8.93 → +0.43 SAP. Corpus within-0.5 67.0%
(MAE 1.025) and /tmp 71.2% (MAE 0.889) — both NET ABOVE the pre-rafters
baseline (66.9% / 70.6%). Worksheet harness 47/47; regression = only the
3 pre-existing fails; pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
`u_roof` only implemented the joist column, so roofs lodged insulated at
rafters (`roof_insulation_location == 1`) were mis-billed at the joist U
on both the API and Summary paths — under-stating loss, over-rating SAP.
RdSAP 10 §5.11.2 Table 16 (spec p.42-43) gives a distinct "insulation at
rafters" column (2): the rafter cavity is shallower than a loft void, so
the same depth yields a higher U (200 mm: rafters 0.29 vs joists 0.21).
§5.11 Table 18 (p.45) likewise carries a rafters column (2) for unknown /
as-built thickness (footnote (1): "The value from the table applies for
unknown and as built") — band A-D = 2.30, E = 1.50, F = 0.68, diverging
from the joist column's 100 mm-equivalent 0.40 default (footnote (4)).
- add `_ROOF_RAFTERS_BY_THICKNESS` (Table 16 col 2) + `_ROOF_RAFTERS_BY_AGE`
(Table 18 col 2) to rdsap_uvalues; `u_roof` selects them via a new
`insulation_at_rafters` flag (ignored for flat / sloping-ceiling roofs).
- `heat_transmission` derives the flag PER BUILDING PART from
`roof_insulation_location` (gov-API int 1 / Summary "R Rafters"), which
also fixes the multi-part dedup-roof-join problem: each part's own
location now drives its U, replacing the unattributable joined
`epc.roofs[]` description.
Worksheet-validated to 1e-4: simulated case 41 (4-bp — Ext1 rafters 200mm
→ 0.29, Ext3 rafters As-Built band F → 0.68; roof total 24.8350) and case
42 (6 variants — rafters 50mm → 0.88, rafters unknown band C → 2.30,
joists/none unchanged). Case 40 stays exact (roof 35.340, total 441.1606);
worksheet harness 47/47.
Corpus within-0.5 66.9% → 66.5% (gates 0.65/1.08 hold) — a spec-correct
shift, NOT a regression: all 15 corpus rafter certs carry redacted (None)
thickness yet lodge roof EER 2-4 (insulated), so the open API blanked a
specified thickness and the spec's unknown-rafter 2.30 default correctly
over-states them. Recovery needs a roof-EER→thickness inference on the
API path (follow-up), not a change to the U-table.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
End-to-end API-path regression pin for the battery behaviour validated by
the user-simulated Elmhurst worksheet pair (cert 001431 "simulated case
35/36", 5 kWh, export-capable, mains-gas, standard tariff). The official
SAP rating ("10a. Fuel costs - using Table 12 prices") values PV used-in-
dwelling and PV exported identically at 13.19 p/kWh (export code 60 ==
import code 30, ADR-0010), so a battery only redistributes PV between two
equally-priced lines: worksheet PV credit (252) = -455.6458 and SAP (258)
= 88.0859 are IDENTICAL with/without the battery (ΔSAP = 0).
Two tests over the committed RdSAP-21.0.1 corpus:
- standard tariff (meter 2): toggling the battery holds continuous SAP
EXACTLY constant, while at least one cert's primary energy DOES respond
(proving the App-M1 §3c β-split is wired, not a dropped battery).
- off-peak tariff (meter != 2): the battery STRICTLY raises SAP, because
self-consumed PV displaces high-rate import (15.29) above the 13.19
export credit — confirming the standard-tariff neutrality is a price
coincidence, not a no-op.
Guards table_32 export price (code 60) and the battery β-split against
silent regression. Complements the unit-level β tests in
test_photovoltaic.py.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
SAP 10.2 Appendix M1 (PDF p.94): "EPV,ex,m = 0 if the PV system is not
connected to an export-capable meter." The cascade computed the β-split
export stream regardless of `is_dwelling_export_capable`, so a non-export-
capable dwelling was credited the full PV export — in the §10a COST it
credits at the Table 32 import rate (13.19 p/kWh), which dominates the rating.
On 7 Wybourn Terrace S2 5BJ the PE (144 vs lodged 151) and CO2 (27 vs 29)
already matched, yet the phantom export cost credit pulled SAP from ~73 to
92.1 (+19). Zero `epv_exported_monthly_kwh` after the Appendix-G4 diverter
adjustment when not export-capable; the onsite (EPV,dw) consumption and the
diverter HW reduction are unchanged.
Not-export-capable PV cohort (corpus, 4 certs): 7 Wybourn +19.1 -> +6.5,
4 Lime Ave +11.1 -> +0.4, 8 Hatherleigh +7.6 -> -0.2, Flat 5 ~-0.4. Gauge
66.1% -> 66.9%, MAE 1.124 -> 1.039. Floor 0.64 -> 0.65 / ceiling 1.18 -> 1.08.
Worksheet harness 47/47 0 diverge (Summary certs carry export-capable meters).
1 AAA test, pyright net-zero. Found by auditing the worst over-rater without a
worksheet: PE/CO2-match + cost-miss localised it to the PV export credit.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
RdSAP 10 §10.5 (PDF p.55): "If the actual size is not determined, the size of
a hot-water cylinder is taken as according to Table 28." When a cylinder is
present (has_hot_water_cylinder) but no size descriptor resolves — the gov API
lodges cylinder_size=0, or Exact with no measured volume — `_hot_water_
cylinder_volume_l` returned None, silently dropping BOTH the cylinder's
storage loss and the Table 13 electric-DHW high-rate fraction, under-costing
and over-rating the dwelling. Default such cylinders to the Table 28 baseline
"Normal" 110 L (the value §10.7 also instantiates as the first-row default).
The context-dependent Inaccessible 210/160 values are deliberately NOT applied
here — they are tied to the explicit "Inaccessible" descriptor (code 5) the
assessor lodges, not to an unpopulated size field.
Scope: 7 of 301 cylinder certs in the corpus (2%). Correctness fix — closes a
real spec gap; marginal on the headline (within-0.5 66.1% unchanged, MAE
1.128 -> 1.124) because these certs' residual is dominated by a separate HW-
demand gap, not the cylinder. Worksheet harness 47/47 0 diverge (Summary certs
lodge a real size, so the fallback never fires). 1 AAA test, pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
SAP 10.2 Table 12a Grid 1 (PDF p.191): electric storage heater SAP code 408
is an "Integrated (storage + direct-acting) system" with a 0.20 space-heating
high-rate fraction on a 7-hour tariff — NOT the 0.00 of "other storage
heaters". `_table_12a_system_for_main` returned None for all storage codes (an
explicit TODO), so code 408 fell back to the 100%-low-rate path and billed
space heating at the bare 7-hour low rate (5.50 p/kWh) — under-costing →
over-rating. Mapped cat-7 storage: 408 -> INTEGRATED_STORAGE_DIRECT (0.20),
others -> OTHER_STORAGE_HEATERS (0.00, unchanged behaviour). The enum +
fraction rows already existed; this only wires the dispatch, so the split
flows self-consistently to both the §10a cost and the Appendix-M1 D_PV
high-rate fraction.
Corpus: sap408 over-raters +14.6/+12.9/+12.7 -> +7.1/+5.1/+3.4 (two crossed
into within-0.5). Gauge 65.9% -> 66.1%, MAE 1.160 -> 1.128. Floor 0.63 -> 0.64
/ MAE ceiling 1.22 -> 1.18. Worksheet harness 47/47 0 diverge. The residual
+3..+7 is the "all other uses" 0.90 high-rate fraction (lighting/pumps/HW
still billed 100%-low on the off-peak legacy path) — the next slice.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
SAP 10.2 Table 4c(3) (PDF p.169) "Factor for controls and charging method"
multiplies a heat network's heat requirement by 1.05-1.10 for FLAT-RATE
charging (note d: household pays a fixed amount regardless of heat used, so
no incentive to economise), and by 1.0 for charging linked to use. The
worksheet folds it into the heat-network requirement alongside the Table 12c
distribution loss factor:
(307) space = (98c) x (302) x (305) x (306)
(310) DHW = (64) x (305a) x (306)
Our cascade applied (306) DLF but never (305)/(305a), so every flat-rate
community-heating cert under-counted demand -> over-rated SAP.
Folded the factor into the 1/DLF efficiency override at the space-heating
(206) and DHW (water-inherits-from-main) sites. Space column adds +0.05 for
no thermostatic control (2301/2302); DHW column is 1.05 flat-rate / 1.0
linked-to-use.
Corpus (RdSAP-21.0.1, 1000 certs): community cluster median +0.32 -> -0.19,
within-0.5 38% -> 62% (control 2307 +0.83 -> -0.19; 2306 unchanged at factor
1.0 as spec requires). Overall gauge 65.0% -> 65.9%, MAE 1.174 -> 1.160.
Ratcheted the corpus-test floor 0.62 -> 0.63 / MAE ceiling 1.25 -> 1.22.
Also records (corpus-test comment + scripts/decompose_co2_pe_error.py) the
disproof of the prior "CO2/PE +5% is a factor/scope bug" lead: factors are
spec-exact, scope identical, and the bias is per-cert demand fidelity
(corr(SAP-err, PE-diff) = -0.54), not a one-slice factor fix.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Adds a committed integration test driving the full API path — raw gov-EPC
response → from_api_response → cert_to_inputs → calculate_sap_from_inputs —
across all 1000 certs in the in-repo RdSAP-21.0.1 corpus, and pins the
aggregate accuracy of our continuous SAP (plus CO2 and primary energy)
against each cert's lodged figures. Mirrors scripts/eval_api_sap_accuracy.py
but runs in CI off the committed corpus (~2s, no /tmp sample needed).
Scoped to RdSAP-21.0.1 — the SAP 10.2-era schema whose lodged rating uses the
same methodology we compute (a fair target). Pre-SAP10 schemas (17.x-20.0.0)
lodge SAP 2012 ratings and are out of scope (guarded for mapping only by
test_mapper_corpus.py).
Current: SAP within-0.5 = 65.0%, MAE = 1.174 (tight floor/ceiling — the
optimised gauge). CO2 MAE = 0.27 t/yr (bias +0.17) and PE MAE = 14.6
kWh/m2/yr (bias +8.9) are reported + loosely guarded: cost is well-calibrated
but CO2/PE both run ~+5-10% high (uniform across fuels — a systematic
CO2/PE-factor or scope gap, not yet investigated). Thresholds ratchet as
slices tighten each metric.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This branch's objective is the SAL ingestion handler
(applications/SAL/handler.py) and its dependency tree. Drop work
that crept in but is unreferenced by it:
- EPC feature: domain/epc, infrastructure/epc (gov_uk + historical
clients), tests/infrastructure/epc
- datatypes/epc edits (instantaneous_wwhrs Optional) reverted to main
- asset_list/app.py local data-file/column tweak reverted to main
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
