Two more boiler-upgrade cascade pins, validating the existing generator across
fuels and cylinder states (no source change):
- oil combi: an oil boiler (fuel 28, code 130) on a mains-gas street converts to
a gas condensing combi (fuel 28->26, code 104). Proves the non-gas -> gas
conversion gated on a mains-gas connection (ADR-0024 revised).
- already-insulated cylinder: a gas boiler heating a pre-jacketed cylinder
(type 2 / 80 mm, no thermostat) gets a new boiler + a thermostat, with the
jacket NOT re-applied. Proves the cylinder path's skip-jacket branch against a
real cert. (Sourced from an LPG re-lodgement whose fuel the Summary mapper
reads as mains gas 26 — a separate LPG fuel-mapping gap, noted in the test.)
Both pin delta 0 (SAP/CO2/PE) against the relodged after.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Extend the gas-boiler-upgrade Option to combi (no-cylinder) dwellings and add
the controls upgrade shared by both boiler shapes. A dwelling has a cylinder or
it does not, so the one `gas_boiler_upgrade` Option is shaped per dwelling:
- no cylinder -> a gas condensing combi (Table 4b code 104), no cylinder fields
touched;
- a cylinder -> a regular boiler (code 102) heating it, with the conditional
cylinder jacket/thermostat (slice 1).
Controls: bring an inadequate boiler control up to full programmer + room
thermostat + TRVs (SAP 10.2 Table 4e Group 1 code 2106). "Inadequate" = the
Group-1 codes with NO room thermostat (2101, 2102, 2107, 2108, 2109, 2111) —
these lack boiler interlock (Table 4c(2) / footnote c) p.171), so adding a room
thermostat genuinely improves SAP. Room-thermostatted (2103/2104/2105/2106/2113)
or better zone controls (2110/2112) are left unchanged — never downgraded, so
no phantom uplift. The with-cylinder cert (control 2106) is therefore untouched
and its pin still holds at delta 0.
Validated by the combi before/after re-lodgement (cert 001431, gas boiler
upgrade - no cylinder): control 2111 "TRVs and bypass" -> 2106, fan flue
False->True, SAP code 112 -> 104. Cascade-pinned delta 0 (SAP/CO2/PE). Removed
the slice-1 placeholder test asserting no boiler Option fires without a cylinder
(the combi Option now correctly fires there).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Add the first boiler-upgrade option to the single "Heating & Hot Water"
Recommendation (ADR-0024 expansion): a dwelling whose existing wet boiler heats
a hot-water cylinder is offered a new gas condensing boiler, with the cylinder
jacketed when under-insulated and given a thermostat when absent. One competing
Option (the Optimiser picks <=1), folded into one composite Plan line.
The end-state is read from the Elmhurst before/after re-lodgements (cert 001431,
gas boiler upgrade - with cylinder), which REVISE ADR-0024:
- Target is always a gas condensing boiler, not fuel-preserving: every after
lodges fuel 26. Gas->gas always; a non-gas wet boiler ->gas only with a
mains-gas connection; electric boilers are left alone (electrification is the
upgrade path). Eligibility = wet-boiler SAP code (Table 4a/4b 101-141 /
151-161 / 191-196) + not an electric boiler + mains gas present.
- End-state is a Table 4b SAP code, not a PCDB index: code 102 (regular boiler
+ cylinder). The calculator derives the condensing seasonal efficiency from
the code, so no efficiency input exists or is needed.
- A modern condensing boiler has a fanned flue: the after flips
`fan_flue_present` False->True on every cert (SAP 10.2 Table 4f flue-fan +
the Table 4b condensing-efficiency basis). Added as a new HeatingOverlay
field, routed to main_heating_details[0].
- Cylinder thermostat is always added when absent (user-locked); the jacket is
the 80 mm `cylinder_insulation_type=2` end-state, applied only when the
cylinder is below 80 mm (never downgrading a better one). Both are conditional
per-dwelling components, not a frozen overlay.
Cascade-pinned delta-0 (SAP/CO2/PE) against the relodged after via
`_assert_overlay_reproduces_after`. NB the absolute SAP on this dwelling is
subject to a separate Summary-path mapper roof-fidelity gap (we read the roof
better-insulated than Elmhurst, scoring ~75 vs the printed 56); the gap is
identical on before+after (the boiler measure never touches the roof) so it
cancels and the pin still proves the exact heating field-delta. Tracked on the
calculator branch.
Wires the new `gas_boiler_upgrade` MeasureType through contingencies (0.26),
the offline sample catalogue, the catalogue-coverage list, and the ARA
first-run integration seed (the option fires on any mains-gas boiler+cylinder
dwelling).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Session 9 ran five independent data-driven audits (profiler, dropped-field scan,
CO2/PE reconciliation, cross-provider LIG parity, HW-demand reconciliation) — all
converged on diffuse remaining gap — and shipped glazing Table-24 (+16 certs) +
HW-only heat-network DLF, taking 54.90% -> 56.8% within-0.5. The data-driven seam
is exhausted; session 10 switches to worksheet-level ground truth via the
summary-report-based per-cert audit. New agent prompt at HANDOVER_SUMMARY_AUDIT.md
with method, starter candidate certs, ruled-out list, and conventions.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The heat-network HW distribution-loss override fired only when the MAIN was
a heat network AND whc inherited from main ({901,902,914}). Water-heating-only
heat networks (SAP 10.2 Table 4a HW codes 950 boilers / 951 CHP / 952 heat
pump) were missed entirely: their Table 4a plant efficiency applied with NO
distribution loss, so the HW fuel was under-counted by the Table 12c DLF
(1.33-1.48x) → under-cost → over-rate.
RdSAP 10 §10 (spec p.36): a water-heating-only heat network is calculated 'for
plant efficiency, distribution loss and pumping energy - see Table 12c'. Added
a whc-gated branch (independent of the main) applying water_eff = plant_eff /
DLF — the per-kWh-generated cost model (q_generated = q_useful x DLF). Fires on
the WHC alone so a HW-only heat network with a non-network main (cert 9093, whc
950 + warm-air main 502) is covered.
The 3 corpus whc=950 certs all improve in |err|: 2153 +2.62->-0.48 (now within
0.5), 7220 +1.27->-0.97, 9093 +6.04->+3.60 (residual is its warm-air main, a
separate cause). within-0.5 56.66->56.79%, within-1.0 71.9->72.2%, mean|err|
down; only those 3 certs change. New AAA test pins the DLF scaling fires on the
WHC independent of the main. Goldens + gate green, pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Forcing-function guards so a lodged-but-unmapped code surfaces loudly instead
of silently taking a wrong-but-plausible default (the class that hid single
glazing as U=2.5 until this session). Four silent fallbacks converted to raise
on PRESENT-but-unmapped codes, while keeping the legitimate ABSENT (None)
defaults:
- _api_glazing_transmission: unmapped glazing_type -> UnmappedApiCode (was
None -> u_window all-None default 2.5).
- _api_cascade_glazing_type: unmapped glazing_type -> UnmappedApiCode (was
pass-through -> wrong g-value slot).
- seasonal_efficiency: a lodged code/category resolving in neither
_SPACE_EFF_BY_CODE nor the category/room-heater fallbacks -> UnmappedSapCode
(was blind 0.80 gas-boiler default, which 'catastrophically misrates heat
pumps and storage' per the table comment). Data-free calls keep 0.80.
- water_heating_efficiency: WHC in no SAP 10.2 Table 4a HW row ->
UnmappedSapCode (was blind 0.78). Absent code keeps 0.78.
Zero current-corpus impact (909 computed / 0 raises, 56.66% within-0.5
unchanged) — the code/efficiency tables are complete for today's data, so
these are guards for the ongoing audit + future data refreshes. Verified the
WHC table already covers 908 (multi-point gas) and 950 (HW heat network), so
those are NOT unmapped-code bugs. 8 AAA tests, goldens + gate green, pyright
net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The g-value tables (_G_PERPENDICULAR_BY_GLAZING_TYPE solar g⊥,
_G_LIGHT_BY_GLAZING_CODE daylight g_L) are keyed on the SAP 10.2 Table 6b
cascade enum, but _api_cascade_glazing_type only translated code 1. Codes 4
and 5 sit in the 1-6 range where RdSAP-21 and the cascade enum disagree
(RdSAP-21 4=secondary/5=single vs cascade 4=double-low-E/5=secondary), so an
API single-glazed window read the cascade-5 secondary g (0.76/0.80) instead
of single (0.85/0.90), and a secondary window read cascade-4 double-low-E
(0.63). Added the {4:5, 5:1} remap entries the existing design comment
already anticipated ("only divergent codes need a remap").
Correctness fix: solar/daylight gains are second-order, so eval is unchanged
(56.66% within-0.5, 0 certs flip) — the dominant single-glazing error was the
U-value, closed in a0432977's Table 24 transmission map. This closes the
keying inconsistency to prevent future drift. 4 AAA tests, goldens + gate
green, pyright net-zero (38=38).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The API glazing-transmission table mapped only the double-glazing codes
[1,2,3,13,14]; single (5/15), secondary (4/11/12) and triple (6/8/9/10)
glazing codes returned None from _api_glazing_transmission, so the cascade
silently routed them to the u_window all-None default U=2.5 instead of their
RdSAP 10 Table 24 (spec p.50) value. Single glazing (U=4.8) was the worst:
modelled at half its true heat loss → systematic over-rate (cert 0370-2933,
7 single-glazed windows, +17 SAP).
Extended _API_GLAZING_TYPE_TO_TRANSMISSION + the gap-keyed override table
with the Table 24 (U, g, frame-factor) rows for every RdSAP-21 glazing code
(single 4.8/g0.85; secondary normal-E 2.9 / low-E 2.2 /g0.85; triple
pre-2002 2.4/2.1/2.0 by gap, 2002-2022 2.0, all g0.68/0.72; known-data
codes 7/8 alias their family default). 94 corpus certs carry an unmapped
glazing code (code 5 = 79); they sat at 32% within-0.5 vs 54.9% baseline.
Eval: within-0.5 54.90% -> 56.66% (net +16 certs: 22 in, 6 offsetting-error
out), within-1.0 70.2 -> 71.9%, mean|err| 1.224 -> 1.203, 909 computed / 0
raises. Spec-applied uniformly per the determinism principle. 7 AAA tests,
goldens + gate green, pyright net-zero (38=38).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Record the 4-agent audit, the shipped Tier-1 fuel-code strict-raise (7878a969),
and the un-actioned Tier 2/3 candidates (glazing codes 4-12, window orientation,
age-band swallows) for a future robustness slice.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Tier-1 finding of the silent-fallback audit. The fuel-type helpers fed the
SAP 10.2 Table 12/32 cost/CO2/PE lookups via a silent
`API_FUEL_TO_TABLE_12.get(fuel, fuel)` passthrough at 5 sites
(_heat_network_factor_fuel_code, HW CO2/PE, _secondary_fuel_code, PV). A fuel
code in NEITHER the API enum map NOR the Table-12 numbering passed straight
through to the mains-gas default baked into unit_price_p_per_kwh /
co2_factor_kg_per_kwh / primary_energy_factor (table_12.py:233/274/287,
table_32.py:190) — silently mis-pricing a novel/colliding fuel as grid gas.
This is the class that mis-priced cert 8536's community biomass as
electricity (-17 SAP) before a7761ea8.
New _table_12_factor_fuel_code mirrors .get(fuel, fuel) EXACTLY for every
recognised input (union of the CO2/PE/price/monthly table keys +
API_FUEL_TO_TABLE_12 values) and raises UnmappedSapCode only when the
resolved code is recognised by no table — surfacing the gap loudly per the
strict-raise principle (reference_unmapped_sap_code). Verified behaviour-
preserving: 0/909 corpus certs hit the new raise; eval unchanged at 54.9%
within-0.5 / 909 computed / 0 raises.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Profile-driven re-sweep at HEAD da094feb. Every biased/error-carrying bucket
chased field-by-field resolved to proxy / already-deproven / already-fixed:
roof code 5/8 (same u_roof as code 4), per-bp age mapping (correct),
'(same dwelling above)' roofs (5 certs, 4 fine), index-less MEV gas
(centred by e6dda705 to signed +0.09), wit=4 cavity -0.25 (tail-driven),
community whc=903 HW (= deproven meter_type=3). The +32 outlier 2958 is
per-cert (twin 3420 is +0.18). Residual is a broad per-cert fabric+HW tail.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Completes the MEV fan-electricity thread. The PCDB-index slice closed the
9 MEV certs carrying a Table 322 record; the other 11 (mostly gas houses)
lodge mechanical_ventilation=2 with NO PCDB index, so
`_mev_decentralised_kwh_per_yr_from_cert` returned 0 and billed no fan
running cost — a tight +2.2 SAP over-rate (signed +1.23, median +2.19).
SAP 10.2 §2.6.3 / Table 4g note 1 (PDF p.176) prescribes a DEFAULT
specific fan power of 0.8 W/(l/s) for an MEV system whose fans are not in
the PCDB, used directly as SFPav in the §5 Table 4f (230a) formula
(SFPav × 1.22 × V). Restructure the helper: when no Table 322 record
resolves, fall back to the default for a mechanical-extract system
(`mechanical_ventilation_kind == EXTRACT_OR_PIV_OUTSIDE`); natural /
balanced (MVHR / MV) systems still contribute nothing.
Index-less extract cohort closed +1.23 -> +0.18 signed (each gains
~1.1 SAP of fan electricity). This is a spec-correct fix that improves
the aggregate but is a HEADLINE TRADE-OFF: within-2.0 83.6% -> 84.6%,
within-1.0 70.08% -> 70.19%, mean|err| 1.232 -> 1.224, but within-0.5
55.12% -> 54.90% (-2) — the fan energy is only ~half each cert's
over-rate, so the cohort lands at ~+1.0 (still outside 0.5) while two
borderline certs with offsetting errors cross out. Applied uniformly per
the determinism principle ([[feedback_software_no_special_handling]]):
the unmasked residual (~+1.0 on gas-house MEV) is the next lead.
1 AAA test (default SFP 0.8 × 1.22 × V for index-less MEV, 0 for
natural). Goldens + full calc/epc regression green (000565 MEV uses its
resolvable PCDB record, unaffected); pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Follow-up to the §2 MV-kind slice. Once MEV dwellings stopped
under-stating their ventilation HEAT loss, a +0.9 SAP over-rate residual
remained — the MEV FAN ELECTRICITY (§5 Table 4f line (230a),
`SFPav × 1.22 × V`, PCDB Tables 322 decentralised-MEV + 329 in-use
factors). `_mev_decentralised_kwh_per_yr_from_cert` already composes it,
but reads `epc.mechanical_ventilation_index_number` +
`epc.mechanical_vent_duct_type`, and the API builder
(`from_rdsap_schema_21_0_1`) never set either — so `pcdf_id is None`
short-circuited the fan energy to 0 on every API cert (the Summary/
Elmhurst path set them, so cert 000565 already billed it).
Wire both schema fields through the 21.0.1 API construction (the corpus
schema). Eval: the 9 MEV certs carrying a PCDB index closed +0.90 ->
+0.13 signed (fan electricity now billed); headline within-0.5 55.01% ->
55.12%, mean|err| 1.233 -> 1.232, 909 computed / 0 raises. Only those 9
certs move (clean diff). The 11 index-less MEV certs still sit at +1.36 —
they need the SAP Table 4h DEFAULT specific fan power (no PCDB record), a
separate slice.
New end-to-end test + fixture (cert 1300, Titon-class dMEV index 500777,
Flexible duct): from_api_response preserves the index + duct type and
(230a) resolves to a positive fan-energy contribution. Goldens + full
calc/epc regression green; pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The profiler flagged `mechanical_ventilation=2` as a clean systematic
over-rate: 20 certs, signed +1.90 SAP, only 5% within 0.5 (every one
positive). Root cause: the API path (`from_api_response`) dropped the
doc-level `mechanical_ventilation` field, so `sap_ventilation.
mechanical_ventilation_kind` was always None and the §2 cascade
defaulted to NATURAL — under-stating the ventilation air-change rate
(and hence heat loss) for every mechanical system. (Only the Elmhurst/
Summary path mapped it, via `_ELMHURST_MV_TYPE_TO_KIND`.)
RdSAP-Schema-21 `mechanical_ventilation` enum (epc_codes.csv) →
MechanicalVentilationKind picking the SAP 10.2 §2 (24a..d) effective-ach
formula:
0 natural -> NATURAL (24d)
1 MV (no heat recovery) -> MV (24b)
2 mechanical extract, dc (MEV) -> EXTRACT_OR_PIV_OUTSIDE (24c)
3 mechanical extract, c (MEV) -> EXTRACT_OR_PIV_OUTSIDE (24c)
5 positive input from loft -> NATURAL (loft-sourced PIV adds no
system air change per RdSAP 10 §2.6)
6 positive input from outside -> EXTRACT_OR_PIV_OUTSIDE (24c)
Code 4 (MVHR, 24a) is DEFERRED — its formula needs the lodged
heat-recovery efficiency (PCDB Table 326) the API→cascade path doesn't
yet plumb; mapping it to MVHR with a null efficiency would mis-model it
as MV, so it stays NATURAL (3 scattered certs, accurate at the median).
Unmapped integers raise `UnmappedApiCode` (mirror of `_api_sheltered_
sides` / `_api_type_1_gable_kind`).
Eval: the extract cohort (mech_vent 2/3/6) moved +1.90 -> +0.9 median
(within-0.5 5% -> 35%); 20 improved / 3 regressed (offsetting). Headline
within-0.5 54.24% -> 55.01%, within-1.0 69.64% -> 70.08%, mean|err|
1.248 -> 1.233, 909 computed / 0 raises. The +0.9 residual on MEV is the
fan electricity (§2.6.4 SFP, PCDB Table 322) — a separate follow-up.
2 AAA tests; goldens + full calc/epc/parser regression green; pyright
net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Audit of the API-SAP error (53% within 0.5) localised the systematic
under-rate to ELECTRIC FLATS (houses sit at 60-66% within 0.5; electric
flats 13-19%). Decomposing the flat error showed it tracks space-heating
demand per m² — the worst certs reach 130-289 kWh/m² (accurate certs sit
at 14-110), i.e. a grossly over-stated fabric heat loss, amplified ~4x by
the electricity unit price and the steep low-band SAP log curve.
Root cause: the gov-EPC API lodges `sheltered_wall="Y"` on alternative
wall sub-areas (a sub-area adjacent to an unheated buffer — stair core,
adjoining structure), but the field was dropped by the schema + domain
dataclasses and the calculator billed the alt sub-area at its full
exposed U. RdSAP 10 Table 4 (PDF p.22) "Sheltered": such a wall carries
an added external surface resistance R=0.5 m²K/W → U_sheltered =
1/(1/U + 0.5) — the SAME adjustment the main wall already applies for
`gable_wall_type=2` (`gable_wall_sheltered`,
`_SHELTERED_GABLE_ADDED_RESISTANCE_M2K_W`). Cert 0340-2976 (band-A flat,
42 m² sheltered timber-frame alt) over-stated its wall channel by
~58 W/K → walls 128 -> 70 W/K.
Threads the field end-to-end: schema dataclasses (21.0.0/21.0.1) +
domain `SapAlternativeWall.is_sheltered` (default False — the Summary/
Elmhurst path leaves it False, sheltering rides through its lodged
U-value there, so goldens are untouched) + `from_api_response` mapping
`"Y"->True` + `_alt_wall_w_per_k` applying the 0.5 resistance on the
cascade path (lodged-U and basement alt-walls return before it).
140 certs (15% of the corpus) carry a sheltered alt-wall; they under-
rated at median -0.82 / mean signed -1.33 / 23% within 0.5. Eval: 102
improved, 38 regressed (offsetting-error cases — fix is spec-uniform per
[[feedback_software_no_special_handling]]); within-0.5 53.14% -> 54.24%,
within-1.0 67.99% -> 69.64%, within-2.0 81.85% -> 83.50%, mean|err|
1.312 -> 1.248, 909 computed / 0 raises. Goldens (6035, 000565) and full
calc/epc/parser regression green; pyright net-zero.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The gov-API `main_fuel_type`/`water_heating_fuel` enum (epc_codes.csv)
codes 30="waste combustion (community)", 31="biomass (community)",
32="biogas (community)" collide in VALUE with the Table-32 electricity
codes 30 (standard rate), 31 (7-hour low) and 32 (7-hour high). All three
sit in `_ELECTRIC_FUEL_CODES`, so `is_electric_fuel_code` flagged a
community-scheme main as electric and `_is_electric_main` routed its cost
through the off-peak electricity branch — BYPASSING the heat-network rate
in `_heat_network_factor_fuel_code`. Cert 8536 (biomass community, SAP
code 301) was billing at 5.5 p/kWh grid electricity instead of the 4.24
p/kWh heat-network rate → -17.2 SAP.
Per RdSAP 10 §C / SAP 10.2 Table 12 (PDF p.191) the community
waste/biomass/biogas rows are codes 42/43/44 (the same rows the
backwards-compat enum codes 11/12/13 already map to). Add 30->42, 31->43,
32->44 to both API fuel-translation tables.
The remap CANNOT be global (`canonical_fuel_code`): the cascade uses the
bare Table-32 code 30 internally as `_STANDARD_ELECTRICITY_FUEL_CODE`
(the RdSAP no-water-heating immersion default writes
`water_heating_fuel=30`), so a blanket remap mis-prices genuine grid
electricity as community waste (cert 2211 regressed +16 SAP in a
prototype). Instead `_heat_network_community_fuel_code` translates only
when `_is_heat_network_main` is true, at the `_main_fuel_code` /
`_water_heating_fuel_code` fuel-TYPE boundary, where the community
meaning is unambiguous.
Per the strict-raise principle ([[reference-unmapped-sap-code]]), a
heat-network main lodging a colliding community fuel the table doesn't
cover raises `UnmappedSapCode` rather than silently falling through to
the same-numbered electricity code.
Eval (API SAP vs lodged): cert 8536 -17.25 -> -6.51, cert 5036 -6.29 ->
+1.36; mean|err| 1.329 -> 1.312, within-1.0 67.88% -> 67.99%,
within-2.0 81.74% -> 81.85%, within-0.5 held at 53.14%, 909 computed /
0 raises. No golden / calculator regressions.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The new gov EPC API (api.get-energy-performance-data..., Bearer auth) returns
403 "Bad authentication header" with EPC_AUTH_TOKEN but 200 with
OPEN_EPC_API_TOKEN — the token name is misleading (it is the Bearer token for
the new API, not the open-data API). Verified live against
/api/domestic/search. Unblocks the live EPC fetch in run_modelling_e2e.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
