main_heating_category=9 (warm-air systems, NOT heat pump) had no entry
in _SECONDARY_HEATING_FRACTION_BY_CATEGORY, so a warm-air main with a
lodged secondary raised UnmappedSapCode in
_secondary_heating_fraction_for_category — the last calc_raise in the
API sample (cert 0380-2197-2590-2996-2715: warm air mains gas code 506 +
electric room-heater secondary).
SAP 10.2 Table 11 (p.188): a gas/oil warm-air unit falls under "All gas,
liquid and solid fuel systems" (0.10), and electric warm air under
"Other electric systems" (also 0.10) — so 0.10 regardless of fuel. The
warm-air efficiency (Table 4a code→eff: 506→0.70) and Table 4f fan
energy were already wired; this was the only missing dispatch entry.
0380 now computes: SAP 78.1 vs lodged 77 (+1.1; the residual is per-cert
fabric/PV, not the warm-air dispatch — a faithful 0380 worksheet isn't
available, sim case 28 diverges at SAP 57 / code 502 / condensing unit).
Eval: zero raises remain, computed 908→909; mean|err| 1.703→1.702.
Regression green (2448 pass incl. golden 6035 + cohort); pyright
net-zero (44=44).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The boiler-1 and boiler-2 after-certs predate the Vaillant product swap (they
lodge the old aroTHERM index 101413), so rather than wait on regenerated certs
these now snapshot the Vaillant overlay's own output on the before (SAP/CO2/PE
at 1e-4), taken as correct because the same overlay reproduces the corrected
Vaillant cert at delta 0 in the boiler-3 (system-boiler) pin. Drops the xfail
markers and the two stale, now-unreferenced after-cert fixtures.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
API floor_heat_loss=8 is observed on EXTENSION building parts whose
floor sits over a heated space within the SAME dwelling (an upper-storey
extension over a heated room). RdSAP 10 §3 gives an internal floor
between heated storeys no floor heat loss — mechanically identical to a
code-6 party floor. `_api_floor_type_str` had no entry for 8, raising
UnmappedApiCode and blocking certs 0370-2254-6520-2426-5971 and
0997-1206-9806-0715-2904.
Map code 8 to the code-6 no-heat-loss string "(another dwelling below)"
(consumed by heat_transmission's party-floor suppression; != "Ground
floor" so the §5 (12) suspended-timber rule stays inert). Empirically
confirmed against both certs: the no-heat-loss treatment lands them
within 0.5 of lodged (0370-2254 68.92 vs 69; 0997-1206 40.68 vs 41),
whereas Ground-floor / unheated / external mappings miss 0997 by ~4 SAP.
Eval computed 906→908. Regression green (only the pre-existing
test_total_floor_area fails); pyright net-zero (38=38).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The gov EPC API field wall_insulation_thermal_conductivity is OUTPUT
metadata in the openly-published EPC, not an input to the RdSAP10 tool
(Elmhurst) that produced it — its wall entry is Type + Insulation +
thickness only, with no conductivity field. So the RdSAP10 reduced-data
method always uses the SAP 10.2 §5.8 (p.41) default λ=0.04 W/m·K,
whatever code the register lodged.
`_resolve_wall_insulation_lambda_w_per_mk` previously mapped only code 1
(→0.04) and RAISED on others, blocking cert 2090-6909-8060-5201-6401
(code 3 on an internally-insulated 360mm solid-brick wall) with
calc_raise:ValueError. Now it returns the §5.8 default for any code.
Validated: 2090 computes to SAP 73.97 vs lodged 74 (err -0.03); λ of
0.04 / 0.03 / 0.025 all round to 74, and Elmhurst exposes no conductivity
input, so 0.04 is the spec-faithful RdSAP10 value. Eval computed
905→906; mean|err| 1.708→1.706. Regression green (only the 2 pre-existing
stone-wall U failures); pyright net-zero (69=69).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 10 of ADR-0025 costing. The Southern Housing rate table moves from code
constants into ashp_rates.json (structured rows the flat scalar catalogue can't
hold), loaded via AshpRates.from_json. Products takes an injected AshpRates
(default: the committed sheet), so rates are now data -- tunable (e.g.
reuse_distribution_fraction) without a code change, and ready for ETL/DB-supplied
rates later. Behaviour-preserving: the 6 pinned cost tests still hold against the
default, plus a new test proving injected rates drive the total.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The efficient Vaillant aroTHERM plus 5 kW (ADR-0025) now raises SAP even on gas
dwellings, so the Optimiser selects the ASHP bundle far more often -- a deliberate
product shift (user-confirmed). Updated the integration/harness tests:
- ARA multi-measure: ASHP is additive to the kept fabric package -> add to set.
- ARA listed_uprn: is_listed blocks walls AND ASHP (blocks_internal); the gate is
now observable via ASHP (selected unrestricted, blocked listed).
- report three-measures: ASHP + solid-floor displace the fabric stack; assert
their triggers (property_type, main_heating_category / floor).
- console hhr + solid_wall coverage tests: assert the measure is OFFERED as a
candidate (the wiring/eligibility intent), since ASHP now out-competes them in
selection; also assert the optimised package leads with ASHP.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The rich catalogue collection over Product carrying cost-composition behaviour;
records the catalogue-math vs dwelling-interpretation split.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The representative heat pump is now the Vaillant aroTHERM plus 5 kW (index
110257, committed with the generator). boiler-3's after-cert is re-sourced from
the corrected Vaillant relodgement and its cascade pin passes at delta 0
(SAP 63.85 -> 72.30). boiler-1 and boiler-2(instant-HW) pins are xfail pending
their own corrected Vaillant after-certs (_ASHP_PRODUCT_REPIN_REASON).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
SAP 10.2 Table 3 (PDF p.160) names "Direct-acting electric boiler"
verbatim in the primary-loss zero list (alongside electric immersion,
combi, CPSU, integral-vessel heat pump). RdSAP 10 §12 (p.62) classifies
SAP code 191 as the direct-acting electric boiler. Its cylinder is
immersion-heated with no primary pipework, so no primary circuit loss
applies — but `_primary_loss_applies` had no 191 branch, so a 191 main
(main_heating_category 2, "Boiler and radiators, electric") fell through
to the cat-{1,2} boiler branch and accrued ~1177 kWh/yr of phantom
primary loss on the electric-flat segment.
Validated against the cert-2474 worksheet: §4 (59) primary loss = 0,
(64) HW output 1760 (cylinder) + (64a) shower 581. Cert 2474 HW kWh
3585 → 2408; SAP 64.66 → 70.35 (the residual to the lodged 78 is an
Unknown-meter data-fidelity artifact — the register recorded meter_type=3
"Unknown" but the lodged rating used an 18-hour off-peak meter, per RdSAP
§12 / the example worksheets).
Eval mean|err| 1.720 → 1.708 (headline 45.0%, flat ±1 cert — the
electric-flat segment is dominated by the meter data-fidelity artifact).
Regression green (2448 pass incl. golden 6035 + ASHP cohort 1e-4);
pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 9 of ADR-0025 costing. _ashp_option now prices via Products.ashp_bundle_
cost(ashp_cost_inputs(epc)) instead of the flat catalogue scalar; the catalogue
row is still read for its material_id. Pinned on boiler-3: gas reuse dwelling
composes to 15600.60 (decommission 720 + pump 9720 + cylinder 2382.60 + reuse
distribution 2778) with 25% contingency.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 8 of ADR-0025 costing. _existing_system keys on the heating fuel code,
not the mains_gas flag -- the 001431 electric fixtures all lodge mains_gas=True
(gas available at the property) while heating electrically (fuel 30), which the
flag-based check misread as gas (and would have wrongly reused a non-existent
wet system). Electric/gas/oil/LPG map to their categories; empty details ->
NONE; unrecognised -> OTHER (gas-line fallback).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 7 of ADR-0025 costing: the modelling-layer interpretation half of the
split. ashp_cost_inputs derives existing system (mains_gas/fuel/SAP-code),
size band (floor area <= 75 m2), design heat loss (floor_area x 0.05 -- the
chosen proxy over HLC, ADR updated), radiator count (habitable + 3, floor-area
fallback) and reusable-wet-system flag. Catalogue math (Products) stays
EPC-free. ADR-0025 updated to record the floor-area pump-sizing choice.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 6 of ADR-0025 costing. Characterises the distribution clamp built in the
tracer: a radiator proxy below 4 prices as the 4-rad band, above 12 as the
12-rad band, in-range exact.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 5 of ADR-0025 costing. Characterises the pump-band selection built in
the tracer: a design heat loss is rounded UP to the smallest covering band
{5,8,11,15,16+} kW, and loads above the largest band take the top rate. Edge
pins (5.0/5.01/8.0/8.01/11.0/15.0/15.01/25.0) lock the boundaries.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 4 of ADR-0025 costing. ASHP is offered to any house regardless of fuel,
so _decommission now prices a fallback instead of raising: no system -> 0,
electric room/panel heaters -> electric-storage line, anything else -> gas
line (representative default). Never blocks ASHP eligibility.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 3 of ADR-0025 costing. When the dwelling has a reusable wet system,
_distribution charges a power-flush (168) plus _REUSE_DISTRIBUTION_FRACTION
(0.5) of the full radiator band -- a documented stand-in for partial radiator
upsizing at ASHP flow temps, the headline uncertainty in the model. Without a
wet system the full new distribution is priced.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 2 of ADR-0025 costing. _decommission maps the existing system to its
Southern Housing line: gas/oil flat 720, LPG 960 (tank+fuel removal),
electric-storage 570/840 by property-size band. Unmapped systems raise for
now -- the no-system/electric-other/other fallbacks land in the next slice.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
First slice of the per-dwelling ASHP bundle costing (ADR-0025). Products is
the rich catalogue collection over Product, owning the catalogue math: given
a typed AshpCostInputs it sums the applicable Southern Housing rate lines
(decommission + heat-pump band + fixed cylinder + full wet distribution) into
a Cost with the separate 25% ASHP contingency. Pure -- no EpcPropertyData or
calculator. Pinned exact (1e-9) against the real rate sheet. Reuse branch,
decommission variants, fallbacks, band edges and radiator clamp follow.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
When DHW is heated by the main heat pump (WHC 901/902/914 = "from main
system") and the main carries a PCDB Table 362 record,
`_hot_water_fuel_cost_gbp_per_kwh` billed the electric HW at 100% off-peak
low rate (its long-standing TODO). SAP 10.2 Table 12a Grid 1 WH column
(PDF p.191) puts HP-DHW on the ASHP/GSHP-from-database row: 0.70
high-rate fraction at 7-hour and 10-hour → 0.70×14.68 + 0.30×7.50 =
12.526 p/kWh (10-hour), not 7.50 p. The low-rate collapse over-credited
the cat-4 HP-DHW cluster.
Fix: pass the cert WHC into the helper and, for HP-DHW (WHC ∈ {901,902,
914} + PCDB-HP main), bill at the ASHP_APP_N WH blended rate. Electric
IMMERSION (WHC 903) is a different Table 12a row (off-peak immersion 0.17
/ Table 13) and stays on the 100%-low-rate fallback until that slice
lands.
cat-4 cluster (20 certs): mean|err| 2.43→2.11, mean signed +0.06→-0.52
(now per-cert scatter, no systematic bias); cert 9472 +6.4→+3.2, 2789
+6.8→+4.0, 4135 +2.7→within 0.5. Headline mean|err| 1.727→1.720.
Regression green (2447 pass incl. golden 6035 + ASHP cohort at 1e-4);
pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A heat pump that resolves via its PCDB Table 362 index alone (API path,
data_source=1, no Table-4a SAP code) had sap_main_heating_code=None, so
`_table_12a_system_for_main` fell through the 211-227/521-524 code-range
gate to None → the "100% off-peak low-rate" fallback. On a Dual meter
(RdSAP §12 Rule 3 routes heat pumps to the 10-hour tariff) this billed
space heating at 7.50 p/kWh instead of the SAP 10.2 Table 12a Grid 1
(PDF p.191) ASHP/GSHP-from-database row: 0.80 high-rate fraction →
0.80×14.68 + 0.20×7.50 = 13.244 p/kWh. The collapse over-credited the
whole cat-4 heat-pump cluster.
Fix: route any main with a PCDB heat-pump record to ASHP_APP_N regardless
of SAP code (a Table 362 record IS an Appendix-N heat pump by
definition). ASHP_APP_N and GSHP_APP_N share the 0.80 SH fraction at
7h/10h, so ASHP_APP_N is the canonical Appendix-N row for the SH split.
cat-4 cluster (20 certs): within-0.5 45%→50%, mean signed +1.43→+0.06,
mean|err| 3.81→2.43; cert 9472 +15.0→+6.4, 2789 +13.4→+6.8. Headline
45.0%→45.1%, mean|err| 1.757→1.727. Regression green (only the
pre-existing test_total_floor_area fails); pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Electric storage heaters (and CPSU) charge overnight and cannot run
economically on a single rate, so their presence is physical evidence the
dwelling is on an off-peak tariff. RdSAP 10 §12 (PDF p.62) applied Rules
1-4 only for a Dual meter; an "Unknown" (code 3) meter returned STANDARD
without consulting the heating type, so a cat-7 storage main billed its
overnight charge at the standard 13.19 p/kWh instead of the 7-hour low
rate (5.50 p/kWh) — ~2.4x too high → large under-rate.
Two coupled fixes:
- `rdsap_tariff_for_cert`: for an Unknown meter, infer the off-peak tariff
from a Rule-1 CPSU (→10-hour) or Rule-2 storage (→7-hour) main; keep
STANDARD otherwise. Direct-acting/room heaters/heat pumps (Rule 3) are
NOT off-peak evidence (run on demand, exist on single-rate meters) so
they stay STANDARD — billing them 100% at the low rate over-credits.
- `_fuel_cost` now resolves its tariff via the §12-aware `_rdsap_tariff`
(not the raw `tariff_from_meter_type`), so the off-peak branch fires for
these storage certs and the legacy scalar fields bill the low rate.
Mirrors `_is_off_peak_meter`'s existing Unknown+electric heuristic (which
already routes HW/secondary off-peak), closing the main-space-heating gap.
Meter-3 electric cluster: mean |err| 11.18 → 6.52, within-1.0 3 → 5 (cert
7336 -26.1 → -0.16, 0380 -19.9 → +1.0). Eval headline 44.9% → 45.0%, mean
|err| 1.82 → 1.76, mean signed -0.08 → +0.02. A few storage certs overshoot
(other residuals the standard rate was masking).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The main pitched/flat roof U-value was derived from the JOINED text of
every roofs[] entry. A room-in-roof carries its own §3.9/§3.10 shell
area + U-value cascade (Table 17 / Table 18 col 4), so a multi-roof cert
lodged "Pitched, insulated (assumed) | Roof room(s), no insulation
(assumed)" leaked the RR's "no insulation" marker into the main roof's
u_roof → U=2.30 applied to the WHOLE main roof, ~3x over-stating its heat
loss. This is the 4700-family regular-roof-U leak.
`_joined_main_roof_descriptions` drops "Roof room(s)" entries before the
main-roof u_roof, falling back to the unfiltered join only for pure-RR
dwellings (every entry an RR) to preserve their prior behaviour. The RR
shell U is unaffected (computed separately) — golden 6035 stays green.
RR-leak cluster (18 certs, RR "no insulation" + a non-RR primary roof):
mean |err| 6.14 → 4.85, within-1.0 0 → 8, within-0.5 0 → 3. Eval headline
44.8% → 44.9%, mean |err| 1.851 → 1.824, mean signed -0.152 → -0.081. Two
certs overshoot (other residuals the leak was masking); the spec rule is
applied uniformly.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Pins the cylinder-OVERWRITE path the earlier ASHP pins did not exercise:
boiler-1/boiler-2 added a cylinder where none existed, whereas boiler-3's
before is a mains-gas regular boiler (SAP code 101) that already heats its
own cylinder (size 2 / insulation type 2 / 80 mm). The fixed _ASHP_OVERLAY
overwrites it to the heat-pump cylinder (size 4 / insulation type 1 / 50 mm)
and switches the dwelling off mains gas (fuel 26->30, code 101->index 101413
+ category 4). The existing overlay reproduces the re-lodged after at delta 0
on SAP / CO2 / primary energy -- no overlay change needed; immersion_heating_
type is None in both, so that field (the electric-with-cylinder case) is
untouched here.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A roof lodged "Unknown loft insulation" carries roof_insulation_thickness
"NI" (Not Indicated → parsed to 0) or "ND" (None): the thickness is
UNDETERMINED, not zero. RdSAP 10 §5.11.4 (p.44) is deterministic here —
"U-values in Table 18 are used when thickness of insulation cannot be
determined" — so the roof takes the Table 18 age-band default (column (1)
pitched / column (3) flat), NOT the uninsulated 2.30 the Table 16 row-0
lookup returns for a parsed-0 thickness. The "Unknown" text is RdSAP's
rendering of the undetermined-thickness observation, distinct from a
genuine "no insulation" lodgement (which keeps 2.30).
u_roof gains an "unknown"-description branch ahead of the parsed-0 → 2.30
path, gated on undetermined thickness (None or 0). Top-floor flats with
"Pitched/Flat, Unknown ... insulation" were the worst electric-flat
under-raters: roof U=2.30 gave HLP ~3.7 on dwellings rated SAP 69-70.
Cluster (14 certs, roof desc contains "unknown", no "no insulation"):
mean |err| 7.79 → 1.82, within-0.5 1→4, within-1.0 1→6. Cert 9836
roof_w_per_k 58.2→10.1, SAP -27.8 → -3.5. Eval headline 44.4% → 44.8%,
mean |err| 1.944 → 1.851. Two certs overshoot (other residuals the wrong
roof-U was masking); the spec value is applied uniformly regardless.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A floor lodged API floor_heat_loss=6 ("another dwelling below") sits over
another heated dwelling, so it is a party floor with no heat loss (RdSAP
10 §3). The mapper mapped code 6 → None and the heat-transmission step
drove floor exposure solely from the dwelling-level `has_exposed_floor`
flag — which is keyed only on the dwelling_type label and defaults a
"Ground-floor flat" to an exposed floor. So a ground-floor flat above a
basement dwelling kept its full ground-floor heat-loss area.
Map code 6 → "(another dwelling below)" (still != "Ground floor", so the
§5 (12) suspended-timber rule stays inert) and have the cascade suppress
that BP's floor when its floor_type carries the signal, mirroring the
roof's existing "another dwelling above" per-BP party override.
Cert 2115-4121-4711-9361-3686 (ground-floor flat, floor_heat_loss=6):
floor_w_per_k 47.85 → 0; SAP -23.44 → -4.41. Cert 0350-…-6435 -12.38 →
-0.55; 0926-…-9024 -2.35 → -0.82. Eval mean |err| 1.982 → 1.944.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A Summary §14.0 Table 4b gas boiler (SAP code 101-119) lodges no §14.0
"Fuel Type" string in the newer Elmhurst export. The carrier was resolved
only from §15.0 "Water Heating Fuel Type" — fine when the same boiler
heats the water, but a gas boiler paired with a SEPARATE electric
immersion lodges §15.0 "Electricity", so `_elmhurst_gas_boiler_main_fuel`
returned None and the cascade strict-raised MissingMainFuelType.
Cert 001431 boiler-1/boiler-2 "before" variants are exactly this config:
§14.0 SAP code 102/104 (mains-gas boiler), §15.0 electric immersion
(code 909), §14.2 Meters "Main gas: Yes". The meter flag is the
authoritative carrier signal — a 101-119 boiler on mains gas burns mains
gas — so adopt it (SAP10 main_fuel 26 per _ELMHURST_MAIN_FUEL_TO_SAP10
"Mains gas") when §15.0 can't disambiguate. §15.0 gas/LPG still wins when
present (keeps LPG-vs-mains-gas precision); no mains-gas meter + non-gas
§15.0 still strict-raises rather than guessing.
Spec: SAP 10.2 Table 4b "Seasonal efficiency for gas and liquid fuel
boilers" (PDF p.168), rows 101-119. Both certs now resolve main_fuel=26
and compute (was: hard raise).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Second ASHP before/after (boiler 2): a gas boiler whose hot water is electric/
instantaneous (water-heating SAP code 909, no cylinder). The cascade pin passes
at 1e-4, exercising the overlay's water_heating_code reset 909 -> 901 that the
boiler-1 pin (already 901) did not. (After lodges control 2209 vs the overlay's
2210 — SAP-equivalent zone controls.)
Adds an xfail(strict) tripwire test_gas_boiler_instant_hw_before_baselines: the
raw before is not scorable on its own because the mapper maps the 'BGB' gas-
boiler EES code to an empty main_fuel_type (boiler-1's 'RGE' resolves to 26),
so Sap10Calculator raises MissingMainFuelType. Harmless to the pin (the overlay
overwrites fuel -> 30); flips green when the mapper derives mains gas from the
gas-boiler SAP code (separate mapper-front fix). ADR-0024.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A "Pitched, sloping ceiling" (roof_construction == 8) lodges its
insulation in the dedicated `sloping_ceiling_insulation_thickness` field,
not `roof_insulation_thickness` (which stays None — the loft-joist field
is meaningless for a slope-following ceiling). The schema dataclasses
dropped that field, so `from_dict` discarded it and the cascade treated
the slope as uninsulated; worse, the pre-1950 None-fallback forced 0 mm
(U=2.30), over-stating roof heat loss ~74%.
Surface the field on SapBuildingPart (schemas 21.0.0 / 21.0.1) and prefer
it in `_api_resolve_sloping_ceiling_thickness` when it carries a NUMERIC
thickness: "100mm" now reaches Table 17 column (1a) "Insulated slope –
sloping ceiling, mineral wool/EPS" (RdSAP 10 §5.11.3 p.44 — 100 mm →
U=0.40) instead of 2.30. Categorical lodgements ("AB" As Built / "NI")
are not measured thicknesses, so they fall through to the existing
as-built rule (Table 18 col (3) via is_pitched_sloping_ceiling).
Cert 9884-3059-9202-7506 (code 8, age B, sloping 100 mm): SAP −5.54 → +0.06.
Cert 8036-2925-6600-0202: −4.94 → +1.55. No regressions in the roof-8
cohort (the "AB" certs are unchanged). Eval headline 43.8% → 44.3% within
0.5; golden fixtures incl. 6035 green.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Mirror of eval_api_sap_accuracy.py that decomposes each cert's SAP error
into per-component energy/cost deltas WITHOUT generating an Elmhurst
worksheet. Calibrates the consumer price from the certs we already get
right (gas £0.0809/kWh n=291, elec £0.2839/kWh n=326 over |SAP err|<0.4),
then for every cert compares our_component_kWh × price to the lodged
heating_cost_current / hot_water_cost_current / lighting_cost_current and
back-calculates a numeric energy target (lodged_cost / price).
Clusters errors by (component × direction). On the 905-cert sample this
reveals heat:high (we over-state heating energy → under-rate SAP) as the
dominant broken cluster: 332 certs, only 36.7% within 0.5. Output CSV at
<cache>/_cost_decomposition.csv.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The ASHP bundle is a fixed whole-system end-state (confirmed: always the same
contractor cylinder), so the hot-water arrangement is fixed too. The overlay now
sets water_heating_code=901 ("from main system") absolutely, so a combi (909/611)
or electric (903/908) before is reset to HW-from-the-heat-pump — previously the
overlay relied on the before already lodging 901 (true for boiler-1, not in
general). No-op for the boiler-1 pin (stays 1e-4). Cascade pins for combi /
electric-with-cylinder befores await example certs. ADR-0024.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
recommend_heating now receives planning_restrictions in the orchestrator (the
ASHP planning gate); the ASHP bundle joins the free candidate pool for every
house/bungalow. Catalogue + contingency (legacy 0.25) gain air_source_heat_pump;
report.py _triggers_for explains the ASHP trigger; the harness forcing test
covers it. Integration tests seed an air_source_heat_pump MaterialRow (ASHP
fires on every house, the broadest trigger yet). NB the optimiser correctly does
NOT select ASHP for an EPC-band goal — gas->electric does not improve the SAP
cost-rating; ASHP is a CO2/PE measure, selectable once non-EPC goals land. ASHP
bundle COMPLETE (S5-S7). ADR-0024.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A typical mains-gas combi house re-lodged as an air-source heat pump closes at
1e-4 (gas-boiler 1 example from the technical specialist). Closes one named gap
the pin surfaced: a whole-system replacement to a PCDB-indexed system left the
old Table 4a sap_main_heating_code (104) beside the new heat-pump index, and the
stale code won the calculator's efficiency dispatch (hot water billed at boiler
not HP efficiency, ΔSAP 3.98). _fold_heating now enforces the mutual exclusion
of the two efficiency anchors (setting an index clears the SAP code and vice
versa). Also fixed a pre-existing pyright annotation in the lighting applicator
test. ADR-0024.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Adds the air-source heat-pump Option to the competing "Heating & Hot Water"
bundles. Its overlay is the absolute heat-pump end-state (fixed representative
PCDB index 101413 + category 4 + control 2210 + HWP cylinder + single meter +
off mains gas), pinned against the relodged after-cert next slice. Eligibility
is physical/planning only (ADR-0024, research-grounded): any non-flat
house/bungalow, not listed/heritage (PlanningRestrictions.blocks_internal —
conservation is offered with a caveat, not excluded), not already a heat pump;
floor area / built form / fuel / fabric are deliberately not gates. recommend_
heating gains a restrictions param (defaulted). An already-HHR electric house
now correctly gets ASHP as a better end-state.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A 440 mm (>420 mm) solid brick AS-BUILT wall computed U = 1.70 (the
220 mm bucket default) instead of the RdSAP-correct 1.10. The §5.7
Table 13 thickness path only fired for *insulated* brick (external/
internal + thickness > 0); the as-built case fell through to the
Table 6 cavity/solid age-band default.
Spec: RdSAP 10 Specification (9th June 2025), §5.7 "U-values for
uninsulated brick walls, age bands A to E", Table 13 (PDF p.40):
≤200 mm → 2.5, 200–280 mm → 1.7, 280–420 mm → 1.4, >420 mm → 1.1.
Table 6 footnote (b) on the "Solid brick as built" row (PDF p.40):
"Or from 5.7 if wall thickness is other than 200mm to 280mm" — the
thickness table supersedes the flat 1.7 default whenever a documentary
wall thickness is lodged (200–280 mm gives 1.7 either way). The §5.8 /
Table 14 dry-lining R is added on top only when the wall is dry-lined,
per the §5.7 closing sentence.
Validated against the user-generated Elmhurst worksheet "simulated
case 21" (replica of API cert 2818-3053-3203-2655-9204: mid-terrace,
age band B, solid brick as-built 440 mm, room-in-roof). New §3 cascade
pin `test_section_3_wall_u_by_thickness_case21_match_pdf` routes the
Summary through the real extractor + mapper and pins:
(31) 155.1000, (33) 175.6208, (36) 23.2650, (37) 198.8858 — all 1e-4.
External walls Main U → 1.1000; Sheltered RR gable → 1/(1/1.10+0.5) =
0.71 (was 0.92). Pinned on §3 only (case-6 precedent): its code-908
instantaneous multi-point gas water heater has a separate §4 (219) gap.
Cross-check: sim case 20 (220 mm) stays at 1.70 — unchanged.
API SAP accuracy (scripts/eval_api_sap_accuracy.py, 896 computed certs):
% |err| < 0.5 SAP vs lodged: 42.6% → 43.8%; mean |err| 2.045 → 2.010.
Regression: tests/domain/sap10_calculator/ (1861), backend/
documents_parser/tests/ (574), datatypes/epc/ + rdsap golden fixtures
all green (pre-existing test_total_floor_area excepted). pyright strict
net-zero. No solid-brick fixture pin shifted (200–280 mm unchanged).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The 2026 API sample raised UnmappedApiCode on `gable_wall_type` 2 (10 certs)
and 3 (4 certs) — the two RR gable variants beyond Party(0)/Exposed(1).
Sim case 21 (an Elmhurst replica of API cert 2818-3053-3203-2655-9204:
gable_wall_type_1=2, gable_wall_type_2=3) lodges them as "Sheltered" and
"Connected", confirming **2=Sheltered, 3=Connected**.
- Mapper: `_API_TYPE_1_GABLE_TYPE_TO_KIND` gains 2 → `gable_wall_sheltered`,
3 → `connected_wall` (U=0, area deducts — already handled).
- Calculator: new `gable_wall_sheltered` branch. The API path lodges no
per-gable U, so the cascade DERIVES it as RdSAP 10 Table 4 (p.22)
Sheltered = 1/(1/U_wall + 0.5) — back-solved + validated against case 21
(U_wall 1.10 → 0.71) and case 20 (1.70 → 0.92). A lodged U (Summary path)
still rides through as an override.
API sample: 14 raises clear → `computed` 882 → 896, `raise:ValueError` 16 → 2.
Summary path unchanged (Sheltered stays `gable_wall_external` + lodged U, so
cert 000487's hand-built fixture is untouched). 2861 pass (lone
test_total_floor_area pre-existing); pyright strict net-zero (32=32 / 12=12).
NOTE: the derived Sheltered U on cert 2818 lands at 0.92 not 0.71 because the
cascade computes its 440 mm solid-brick wall U as 1.70 (the 220 mm default) —
a SEPARATE wall-U-vs-thickness bug (next slice, validated by case 21's 1.10).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Locks sim case 20 (storage heaters + Detailed RR + loose-jacket cylinder)
as a golden vector: _elmhurst_worksheet_001431_case20.build_epc() routes the
Summary PDF through extractor → mapper → calculator, registered in
test_e2e_elmhurst_sap_score with all 11 SapResult headline pins at 1e-4.
10 pinned exact off slices 1-2 (window extractor, RR stud walls); this slice
closes the last one, co2_kg_per_yr (was 3797.62 vs (272) 3815.4060).
Root cause: on a dual-rate (E7) meter the CO2 path ignored the tariff's
high/low Table-12 electricity codes that the cost path already uses:
- Secondary (direct-acting portable heaters, on-peak) keyed the monthly
Table 12d cascade on standard code 30 (0.15405) instead of the E7 HIGH
code 32 → (263) 0.1616. SAP 10.2 Table 12a Grid 1 direct-acting electric
is 100% high-rate; mirrors the cost side billing it at 15.29 p/kWh.
- Main storage heaters fell through `_table_12a_system_for_main`=None to
the FLAT annual factor (0.136) rather than the dual-rate LOW code: per
the Table 12a design intent ("storage … 100% low rate") they charge
off-peak → E7 LOW code 31 → (261) 0.1357.
case-20 co2 now EXACT. 2433 calculator + 112 golden + documents_parser tests
pass — no dual-meter/storage cohort regression; pyright strict net-zero (32=32).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A Detailed room-in-roof lodges "Stud Wall" surfaces, but the cascade billed
every one through Table 17 from its insulation — over-counting fabric on
internal studs that carry no heat loss. sim case 20's two studs lodge §8.1
Default U-value 0.00 and the P960 worksheet omits them from BOTH fabric heat
loss (§3: (33)=285.9847) and total exposed area (31)=239.68; the cascade
computed ~0.52 each → (33) +4.16 W/K and continuous SAP 43.05 vs 43.6322.
Gate the drop on the lodged Default U-value: 0.00 → internal knee wall,
return None (no heat loss, no area); positive → a real exposed knee wall
(cert 000565 Ext2 Detailed: 0.31 / 0.10) that still falls through to the
Table-17 path. The earlier over-broad "drop all studs" zeroed 000565's
genuine studs — this keeps them.
Pins test_summary_001431_case20_fabric_heat_loss_matches_worksheet_line_33
((33)=285.9847 at 1e-4); case 20 continuous SAP now EXACT (43.6322). 2850
pass (the lone test_total_floor_area failure is pre-existing on base);
pyright strict net-zero (32=32).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Sim case 20's §11 lodges 5 windows but only 1 surfaced. The "W H Area"
cells tokenize inconsistently: a narrow Area column keeps all three on one
line ("1.80 2.10 3.78" — matches _WIDTH_HEIGHT_AREA_RE), but a wider Area
column triggers pdftotext's 2+-space split, dropping the Area onto its own
line ("5.79 2.00" then "11.58"). The 3-decimal data anchor never matched
those four rows, so they were lost — gutting §6 solar gains (5 windows →
1) and dropping continuous SAP 43.05 → 38.32 vs the worksheet's 43.6322.
Pre-merge a "W H" line + a following lone-decimal Area into the canonical
"W H Area" line, gated on Area ≈ W × H (the §11 Area is always the product)
so a frame factor / g-value / U-value below a dimension line is never
absorbed. One-line layouts (3 decimals) are untouched.
Pins via test_summary_001431_case20_extracts_all_five_section11_windows
(Summary_001431_case20.pdf mirrors sap worksheets/golden fixture debugging/
simulated case 20/). 573 documents_parser tests pass; pyright strict net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The first cut of elmhurst_input_sheet.py introspected the `schema`
dataclasses (rdsap_schema_*.py) but the mapper emits the `epc_property_data`
domain types, whose fields differ (wall_thickness_mm not wall_thickness;
total_floor_area_m2 not total_floor_area; frame_material not pvc_frame;
cylinder_insulation_thickness_mm; SapRoomInRoof has gable_*_length_m not
insulation/roof_room_connected). Worse, the getattr-with-None-default helper
printed None over real data, nearly sending a debug session chasing a
non-existent "dimensions dropped" mapper bug on cert 2100 (the dims map
fine; that cert's error is elsewhere). Switched to direct attribute access
so a future rename fails loudly, fixed every field name against the live
domain objects, and added roof_construction_type / floor_type for context.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Reconstructs the per-cert "Elmhurst SAP input sheet" generator that the
API-accuracy debugging loop relied on (the worked example survives at
'sap worksheets/golden fixture debugging/6035_elmhurst_input_sheet.md'); the
original was a throwaway and never committed. Companion to
eval_api_sap_accuracy.py: once that names a worst-offender cert, this dumps
the codes the mapper hands the calculator (from_api_response → EpcPropertyData)
in the 6035 layout — header, lodged element descriptions, building parts +
dimensions, windows, doors/heating/water/vent — plus the lodged reference
outputs and OUR continuous SAP next to the lodged value, to read side-by-side
with the Elmhurst Summary / P960 worksheet PDF.
Reads the fetch_2026_epc_sample.py cache (EPC_SAMPLE_CACHE, default
/tmp/epc_2026_sample). `--out-dir` writes <cert>_elmhurst_input_sheet.md.
Pyright strict clean.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
recommend_heating joins the free candidate pool in _candidate_recommendations;
the HHR storage bundle reaches the optimised package for an electric/off-gas
dwelling. Catalogue + contingency (legacy 0.10) gain
high_heat_retention_storage_heaters; report.py _triggers_for explains the
heating trigger (electric/off-gas main); the harness _GENERATOR_MEASURE_TYPES
forcing test covers it. ASHP + boiler bundles still to come. ADR-0024.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The same absolute-target HHR overlay reproduces the common relodged after from
two different base systems (existing electric storage; "no system present"
electric) — proving the bundle is a true whole-system end-state. Closes one
named gap the pin surfaced: the relodged HHR cylinder lodges
cylinder_thermostat='Y', so HeatingOverlay + _fold_heating + the HHRSH overlay
gain cylinder_thermostat (ΔSAP 0.065 -> <1e-4). ADR-0024.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice f68cea27 (re-homed here as 97f44b53) added a guard to
_is_elmhurst_roof_window — "a window lodged on a wall is vertical by
definition" — to keep 001431's two "Double pre 2002" External-wall units in
the vertical sap_windows list for the Modelling draught-proofing count. But
that guard fires on the §11 `location` string, which is an unreliable
lodging artifact: every one of cert 000516's six §11 rows reads "External
wall", and only the U-value separates the five vertical panes (U 2.8) from
the one genuine rooflight (U 3.1, area 1.18, lifted to 3.40 by the Table 24
lookup). Elmhurst's own worksheet routes that U 3.1 "External wall" unit
through (27a) Roof Windows — so location is NOT a vertical signal and the
U > 3.0 backstop (RdSAP 10 §3.7.1) is what matches the worksheet.
Removing the guard restores both 000516 pins
(test_summary_000516_full_chain_sap_matches_worksheet_pdf_exactly,
test_from_elmhurst_site_notes_matches_hand_built_000516) with no other
regression (2879 pass; the lone test_total_floor_area failure is
pre-existing on the branch base, unrelated to window classification).
The extractor half of 97f44b53 (capturing the standalone "BFRC data" §11
row) is retained — it is independent of this classifier and harmless here.
The 001431 Modelling draught-proofing count must instead include roof
windows (the draught_proofed-on-SapRoofWindow approach noted in the glazing
handover), which is feature/bill-derivation's front, not this branch.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The heating Recommendation Generator (HHRSH first). Emits one "Heating & Hot
Water" Recommendation whose competing whole-system bundles the Optimiser picks
from; this slice builds the high-heat-retention storage Option. Its overlay is
the absolute HHR end-state (Table 4a code 409 + control 2404 + dual off-peak
meter + off-peak electric cylinder), pinned against the relodged after-cert in
the next slice. Eligibility translates legacy is_high_heat_retention_valid to
structured predicates (electric or off-gas main, not already HHR/heat-pump).
mains_gas and the heat emitter are unchanged by the measure, so unset. ADR-0024.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
RdSAP 10 §2 (Ventilation, "Walls" row): "Structural infiltration: 0.25
for steel or timber frame or 0.35 for masonry construction ... System
build: treated as masonry." `_is_timber_or_steel_frame` wrongly included
wall_construction code 6 (system build) alongside code 5 (timber frame),
handing system-build dwellings the 0.25 structural ACH instead of 0.35.
On the cat-10 room-heater fixture (ref 001431, walls SY System Build →
code 6) this under-stated the infiltration rate (18) by exactly 0.10
(0.45 vs worksheet 0.55), dropping the effective air change (25), the
ventilation heat loss (38)m = 0.33 × (25)m × (5), and the heat-transfer
coefficient (39) — so space-heating demand (98) came out 404 kWh low
((211) 11158.6 vs worksheet 11563.2). Restrict the 0.25 branch to code 5
only; code 6 (and everything else) is masonry at 0.35.
Pins the rating-block (38)m ventilation heat loss mean = 83.3613 W/K at
abs 1e-4 and asserts the classifier treats the system-build wall as
masonry. §4 suite green (2415 passed, 1 skipped); no existing fixture
relied on system-build → 0.25.
Residual after this slice: SAP +0.03 / cost -£0.95 — a small fabric (33)
gap (-0.15 W/K) plus lighting (232) +1.0 kWh remain as separate causes.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Water heating SAP code 909 (electric instantaneous) and 907 (single-point
gas) heat water at the point of use, serving one outlet with no
distribution pipework. Per SAP 10.2 §4 (p.23, l.1416): "'Single-point'
heaters, which are located at the point of use and serve only one outlet,
do not have distribution losses either." So worksheet (46)m = 0 and the
heat-required line collapses to SAP 10.2 worksheet l.7704
(62)m = 0.85 × (45)m + (46)m + (57)m + (59)m + (61)m
= 0.85 × (45)m (all loss terms zero for a no-cylinder system).
`distribution_loss_monthly_kwh` already supported the
`is_instantaneous_at_point_of_use` flag (and its docstring already named
codes 907/909), but `water_heating_from_cert` hard-coded it to False, so
the cascade applied (46)m = 0.15 × (45)m to single-point heaters. That
0.15 distribution loss exactly cancelled the 0.85 reduction, leaving
(62)m = (45)m. On the cat-10 room-heater fixture (ref 001431, code 909)
that over-stated the water fuel (219) as 2082.6250 instead of the
worksheet's 1770.2313, and inflated the (65)m heat gains (692.47 vs
worksheet 442.55) which in turn suppressed space-heating demand.
Thread the cert's existing instantaneous flag (`_INSTANTANEOUS_WATER_CODES`
= {907, 909}) through `_water_heating_worksheet_and_gains` into both the
demand-pass and final `water_heating_from_cert` calls.
Pins (219) water fuel = 1770.2313 at abs 1e-4 via the extractor → mapper →
rating cascade. §4 suite green (2414 passed, 1 skipped); no existing
fixture exercised the 907/909 path. The residual space-heating fuel gap
((211) 11158.59 vs worksheet 11563.17) this exposes is a separate cause —
next slice.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
cert 001431's §11 lodges 17 windows but only 14 surfaced, via two distinct gaps:
1. Extractor (_extract_windows_from_layout): the one "Double glazing, known
data" row whose §11 Data-Source cell is "BFRC data" was rejected — it is
laid out as a standalone keyword line with the U-value on the next line
and lodges no Frame Type/Factor/Gap cells, so it never matched the joined
"<source> <U>" Manufacturer-line shape. Now anchored by a standalone
data-source form, with the RdSAP 10 §3.7 default frame factor (0.7) for
the absent frame cell.
2. Mapper (_is_elmhurst_roof_window): the two "Double pre 2002" rows
(U 3.1 / 3.4 > 3.0) were reclassified as roof windows by the U-value
backstop even though both are lodged on an "External wall". A window
lodged on a wall is vertical by definition; guard the U-value backstop so
it only fires when location/BP give no roof signal.
With both closed: 17 sap_windows, 0 misrouted to sap_roof_windows.
Re-homed onto the mapper-validation line from feature/bill-derivation
(orig f68cea27); the modelling-only regression test
(tests/domain/modelling/test_window_extraction_001431.py) stays on
bill-derivation. KNOWN: the mapper guard breaks cert 000516's
test_summary_pdf_mapper_chain pins (W6 U=3.10 routing) — must be resolved
before this PRs to main.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
