`_synthesise_20_0_0_sap_windows` passed `schema.multiple_glazing_type`
straight into `_api_cascade_glazing_type`, which raised UnmappedApiCode on
the "ND" (Not Defined) string that the 20.0.0 corpus lodges alongside the
1-8 integer codes — failing the mapper-coverage guard on every ND-glazed
20.0.0 cert. Mirror the existing 18.0/19.0/17.x seams: route integer codes
through the cascade, fall the "ND" string back to the DG-modal default
(cascade code 2 → daylight g_L 0.80). Also corrects the 20.0.0 schema
field type `int` → `Union[int, str]` to match the data (as 18.0 already
does), which keeps the isinstance guard pyright-clean.
Pre-existing failure (present before this branch's recent commits), not in
the handover regression gate. Fixes all 15 RdSAP-Schema-20.0.0 ND certs;
test_mapper_corpus 6002/6002 pass. pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Completes `_elmhurst_secondary_fuel_from_sap_code` per SAP 10.2 §12
(PDF p.34: "Secondary heating systems and applicable fuel types are taken
from the room heaters section of Table 4a") + RdSAP 10 §10.4.1. Each
Table 4a room-heater code now resolves to its fuel CATEGORY's modal fuel:
- gas room heaters 601-613 → mains gas (26 → Table 32 1, 3.48 p/kWh)
- liquid room heaters 621-625 → heating oil (28 → Table 32 4, 5.44 p/kWh)
- solid room heaters 631-636 → house coal (11 → Table 32 11, 3.67 p/kWh)
- electric room htrs 691-694/699/701 → None (cascade electricity default)
Previously only the gas (601-613→26) and solid (631-634→11) blocks were
mapped; liquid heaters (621-625) and 635-636 fell through to None →
silently billed as electricity (13.19 p/kWh), a large mis-price for an
oil/solid heater. The prior slice raised on those; this maps them to the
correct category fuel instead, and keeps the raise ONLY for codes inside
the room-heater range (601-701) that are not a recognised Table 4a row.
The specific sub-fuel within a category (mains gas vs LPG vs biogas) is a
SEPARATE lodgement per §10.4.1 and is NOT exported in the Summary, so the
gas block stays the modal mains gas — worksheet "simulated case 37" lodged
its 605 live-effect fire on biogas (7.60 p/kWh), unrecoverable from the
Summary code alone (this is the entire +7 SAP case-37 gap: secondary
energy £131 + a separate biogas standing charge £70; every other line
matches the worksheet exactly, incl. (206) main efficiency 61%).
5 AAA tests, harness 47/47 (0 raised), pyright net-zero, regression clean,
corpus gauge unchanged (Elmhurst-path only).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The Elmhurst Summary lodges only the secondary heating SAP code (Table 4a
Category 10), never its fuel. `_elmhurst_secondary_fuel_from_sap_code`
mapped the gas block (601-613 → mains gas) and solid block (631-634 →
house coal) to their modal defaults, but returned None for any OTHER
Category-10 code — and None makes the cascade SILENTLY bill the secondary
as electricity (13.19 p/kWh). For a fuel-fired heater (e.g. 621-625
liquid-fuel oil/bioethanol) that is a large, invisible mis-price.
Per the UnmappedElmhurstLabel strict-raise pattern (mirrors the wall_type
/ glazing label raises), a fuel-fired Category-10 code (601-699) outside
the mapped gas/solid blocks now RAISES instead of guessing. Electric room
heaters (691-699) keep returning None — electricity IS their fuel.
The gas block 601-613 still resolves to the modal default mains gas: the
Summary cannot distinguish mains gas from LPG/biogas, so an LPG or biogas
live-effect fire (worksheet "simulated case 37" used biogas at 7.60 p/kWh
vs our 3.48 p/kWh mains-gas default, a +7 SAP gap) is not recoverable from
the Summary export — that is a data-availability limit, not a guess we can
fix here. This commit closes the genuinely-silent-wrong path; the gas
sub-fuel remains the documented modal default.
Worksheet harness 47/47, 0 raised. 3 AAA tests, pyright net-zero,
regression clean, corpus gauge unchanged (Elmhurst-path only; the API path
lodges the secondary fuel explicitly).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Add the 17.0 synthesis seam over the shared _synthesise_reduced_field_windows
core (inherited 20.0.0 coefficients, ND glazing -> DG-modal default 2, per
ADR-0028). 17.0 glazed_type codes (1-4,7) are a subset of the verified 1-8
space. The 10 rich certs use lodged window_area directly; the windowless 990
synthesise a 4-way N/E/S/W split.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Dispatch RdSAP-Schema-17.0 through from_api_response, parse-fix the schema
(data-driven required->optional, validated against the 1000-cert 17.0 corpus
per ADR-0028 — incl. SapHeating.cylinder_insulation_type and the
has_hot_water_cylinder / has_fixed_air_conditioning / has_heated_separate_
conservatory flags), and port the defensive mapper reads (dwelling_type
str/dict/number, photovoltaic_supply guard, sap_floor_dimensions guard). All
1000 corpus certs now parse and map.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Add the 19.0 synthesis seam over the shared _synthesise_reduced_field_windows
core (inherited 20.0.0 coefficients, ND glazing -> DG-modal default 2, per
ADR-0028). 19.0 glazed_type codes (1-4,6,7) are a subset of the verified 1-8
space. The 6 rich certs use lodged window_area directly; the windowless 994
synthesise a 4-way N/E/S/W split.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Dispatch RdSAP-Schema-19.0 through from_api_response, parse-fix the schema
(data-driven required->optional, validated against the 1000-cert 19.0 corpus
per ADR-0028), and port 18.0's defensive mapper reads (dwelling_type str/dict/
number, photovoltaic_supply guard, sap_room_in_roof Measurement coercion).
All 1000 corpus certs now parse and map.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The gov-EPC API surfaces the assessor's RdSAP-assessed per-element U-values
as `roof_u_value` / `wall_u_value` / `floor_u_value` on each building part.
These were undeclared on the RdSAP 21.0.0/21.0.1 schemas, so `from_dict`
silently dropped them, and `heat_transmission` re-derived each U from the §5.6
/§5.7/§5.11 construction-default cascade. The gov OPEN data routinely redacts
the backing insulation thickness, so that re-derivation mis-bills an insulated
element as uninsulated.
RdSAP 10 §5.1: a known element U-value (documentary evidence / the lodged
RdSAP output) is used directly in place of the construction-default cascade.
Per [[project_per_cert_mapper_validation_state]] the gov API carries RdSAP
OUTPUT, so the lodged U reproduces the official's element heat loss exactly.
Worst case in the 2026 sample: cert 7921-0052-0940-5007-0663, an age-C
"Pitched, sloping ceiling" (rc=8) top-floor flat lodging roof_u_value=0.2 with
no thickness. The cascade returned the uninsulated 2.30 W/m²K → SAP 56.9 vs
lodged 80 (-23.09, the single largest error in the sample). The roof override
alone recovers ~15 SAP; the wall override (lodged 0.34 vs cascade) closes the
rest of this cohort.
Override applies to the MAIN wall only (alt-wall sub-areas keep their own
per-area U) and the part's floor=0. Fires only when the rare field is present
(9 of 909 computed certs), so the Summary path — which never lodges these
API fields — is untouched.
API gauge: 67.1% → 67.7% within-0.5, mean|err| 1.024 → 0.992.
Worksheet harness: 47/47, 0 divergers (unchanged).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
ADR-0028's deferred extraction, triggered by 17.1 as the second instance: the
inherited 20.0.0 coefficients (0.148 + band multipliers + 4-way split) now live
in one `_synthesise_reduced_field_windows` core. The 20.0.0 / 18.0 / 17.1 seams
keep their own names (so each can diverge) but collapse to glazing-type
resolution (cascade + that spec's ND handling) plus a call to the core.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Rich certs (14/1000) use lodged window_area; the windowless majority synthesise
glazing from the glazed_area band via _synthesise_17_1_sap_windows (own seam,
inherited 20.0.0 coefficients); lighting/ventilation/hot-water mirror 18.0.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Behaviour delivered by the band-multiplier dict in the prior slice; this pins
the band-2 ("More than typical") case against the inherited 20.0.0 coefficient.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The gov-EPC API `wall_construction` enum diverges from the calculator's
internal WALL_* code-space (confirmed by the description-vs-code audit across
the corpus): API 1-5 align (granite/sandstone/solid-brick/cavity/timber), but
API 6=basement, 8=system built, 9=cob — whereas the calc constants are
WALL_SYSTEM_BUILT=6, WALL_COB=7, WALL_PARK_HOME=8, WALL_CURTAIN=9. Codes 8 and
9 therefore fell OUT of u_wall's `known_types` and resolved only via the
`walls[].description` fallback, with two failure modes:
- System built (API 8): a cert lodging no description silently defaulted to
cavity (1.5) instead of the system-built U (RdSAP 10 Table 6, e.g. band E
as-built 1.7). Latent in the corpus (all 43 carry a description) but a
silent mis-bill waiting to happen.
- Cob (API 9): a LIVE bug — calc WALL_CURTAIN=9 (set by the Summary path's
"CW" mapping, paired with a curtain_wall_age) intercepts code 9 in the
`construction == WALL_CURTAIN` branch, billing the cob wall at the curtain
default 2.0 regardless of description.
Fix, split by where each can be disambiguated safely:
- System built: `u_wall` gains `_GOV_API_WALL_CODE_TO_TYPE = {8: WALL_
SYSTEM_BUILT}`, resolving code 8 directly (calc WALL_PARK_HOME=8 is never
dispatched, so no collision; gov 6=basement is left to the basement
machinery — cannot remap 8→6).
- Cob: translated at the API mapper (`_api_wall_construction_code`, 9 →
WALL_COB=7) where the source is unambiguously the gov enum — the gov API
has no curtain code, so an API 9 is always cob. Applied to main + alt
walls across the from_rdsap_schema_* builders. The Summary path's "CW"→9
curtain mapping is untouched.
Worksheet harness UNAFFECTED (47/47, 0 divergers — Summary path unchanged).
API gauge 65.1% -> 65.3% within-0.5 (mean|err| 1.075 -> 1.059): the n=1 cob
cert now computes cob instead of curtain. 3 AAA tests (u_wall system-built
without description; mapper cob 9->7; aligned/system/basement pass-through).
pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
`_CYLINDER_SIZE_CODE_TO_LITRES` held only codes 2/3/4 (Normal/Medium/Large →
110/160/210 L); codes 5 (Inaccessible) and 6 (Exact) fell through to None,
so the Table-13 high-rate fraction AND the cylinder storage loss were skipped
for those certs (20 code-6 certs in the API sample).
Per RdSAP 10 Specification (10-06-2025) §10.5 Table 28 (PDF p.55):
- Code 6 "Exact": use the lodged measured volume. The gov API carries it in
`cylinder_size_measured` (e.g. 150 L) — now plumbed through the 21.0.0/21.0.1
schema → mapper → `SapHeating.cylinder_volume_measured_l`.
- Code 5 "Inaccessible": 210 L if off-peak electric dual immersion, 160 L from
a solid-fuel boiler, otherwise 110 L (n=0 in the current sample, but
spec-complete).
New `_cylinder_volume_l_from_code` centralises Table 28 resolution and replaces
the three raw-dict call sites (`_hot_water_cylinder_volume_l`, the cylinder
storage-loss path, and the PCDB performance check) so all three honour codes
5/6 identically. `_cylinder_inaccessible_volume_l` applies the code-5 context
rule via the existing immersion/off-peak-meter/solid-fuel-boiler detectors.
Worksheet harness UNAFFECTED (47/47, 0 divergers): the Summary path lodges
neither code 5/6 nor a measured volume. API gauge: within-0.5 64.4% -> 65.1%
(mean|err| 1.085 -> 1.075) — the 20 code-6 certs now size their cylinder from
the measured volume. 4 AAA tests (code 6 measured; code 5 solid-fuel/default/
off-peak-dual-immersion). pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The Elmhurst Summary §7 lodges "Alternative Wall N Sheltered Wall: Yes" for
a sub-area adjacent to an unheated buffer (e.g. a flat's corridor wall),
but the extractor dropped it and _map_elmhurst_alternative_wall never set
SapAlternativeWall.is_sheltered — so the cascade billed the sub-area at its
full exposed U instead of the RdSAP 10 Table 4 (p.22) sheltered U =
1/(1/U + 0.5).
The calculator already applies is_sheltered (_alt_wall_w_per_k) and the
gov-API path already wires sheltered_wall=="Y"; this brings the Elmhurst
front-end to parity. Three-part change: AlternativeWall.sheltered field +
_alternative_walls_from_lines parse ("Alternative Wall N Sheltered Wall") +
_map_elmhurst_alternative_wall is_sheltered=a.sheltered.
Surfaced by simulated case 34 (cert 001431 electric-storage flat): the
6.02 m² corridor wall billed at full U=1.50 (9.03 W/K) instead of the
sheltered 0.86 (5.18 W/K) — +3.85 W/K, -1.61 SAP. Post-fix the alt wall
matches the worksheet's (29a) 5.177 and case 34 closes from -1.61 to -0.30
(remaining residual is a separate window/wall area-allocation thread).
Elmhurst-mapper only: API SAP gauge unchanged (57.6% within 0.5); worksheet
harness 47/47 unaffected; regression gate green (3 pre-existing fails
unrelated); pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The Elmhurst dwelling-type classifier keyed "Top-floor flat" on a "dwelling
below" floor lodgement. A single-storey flat exposed BOTH top (a real
external roof) AND bottom (floor over partially-heated space, no dwelling
below) therefore fell through to "Ground-floor flat" — which the cascade's
_dwelling_exposure maps to has_exposed_roof=False, dropping the external
roof entirely.
Surfaced by simulated case 34 (cert 001431 reconfigured as a slimline
electric-storage flat): the worksheet bills (30) External roof = 39.98 m²
x U=2.30 = 91.95 W/K — the dominant heat-loss element — but the cascade
dropped it, under-stating space-heating demand by 42% (6550 vs 11357
kWh/yr) and over-predicting SAP by +21.76 (57.07 vs worksheet 35.31).
Fix: an exposed (non-party) roof puts the flat on the top storey
regardless of what is below it. Classify as "Top-floor flat" whenever the
roof is exposed; the flat's exposed floor is recovered downstream by the
existing per-BP is_above_partially_heated_space / is_exposed_floor override
in heat_transmission (§3). Party-roof flats ("another dwelling above") are
unaffected and stay Ground-/Mid-floor.
This is an Elmhurst-mapper (dwelling_type) bug, NOT a calculator bug: the
calculator correctly trusts dwelling_type, and the gov-API path supplies
the position directly (cert 0036 — a genuine ground-floor flat whose API
data lodges a "Pitched, no access" roof construction under another dwelling
— stays party, 2.51 W/K). API SAP gauge unchanged (57.6% within 0.5);
worksheet harness 47/47 unaffected; case 34 roof now exact (residual -1.61
is a separate flat-corridor wall-U thread). Regression gate green (3
pre-existing fails unrelated).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
