SAP 10.2 §4.3 (p.24) scopes itself to "where hot water is provided by a
heat network" and requires the Table 3 primary loss, so the gate keys on
the DHW source. Checked off the WHC before the main-keyed branches so a
non-boiler space main (cert 9093's warm air) can't zero it out.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
950 boilers / 951 CHP / 952 community heat pump differ only in plant
efficiency, which SAP 10.2 §4.3 puts in the Table 12 heat price — so the
dwelling's delivered-heat demand must not vary with it. Passes on the
previous commit's expression; verified RED against the prior impl, where
951 leaked 0.80/0.75 and 952 under-billed its DHW fuel by 3.15×.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
SAP 10.2 §4.3 (p.24) puts the water-heating efficiency in the Table 12
heat price, and C4 (p.53) scopes the plant efficiency to CO2/PE only, so
worksheet (310) = (64) × (305a) × (306) carries no efficiency term. The
dwelling-side divisor was applying it a second time.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Backs out the WHC-950/951/952 primary-loss (d3c0b9e4) and flat-rate-charging
(fecf4f62) changes to cert_to_inputs.py: they fire on ANY cert with those
water-heating codes, regressing the gov-API RdSAP corpus
(test_api_path_sap_accuracy_on_rdsap_21_0_1_corpus MAE 0.627 -> 0.630), and an
Opus audit found the water-only branch has a pre-existing plant-efficiency
double count they flow more kWh through. The calculator work + the correct
fix (water_eff = 1.0/(DLF*1.05)) + an Elmhurst-worksheet regression are
tracked in #1592, isolated from the extractor accuracy PR. The cylinder-
insulation MAPPER fix (f5e4814b) is retained.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Khalim-authorised MAE loosening: coding window orientation exposes the known
SAP-10.2-vs-lodged offset the zeroed solar gains were masking; within-0.5 is
the north-star metric and jumps 20.0% -> 23.9%.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Manually verified in pashub (Khalim, 2026-07-14): deal 499584755922
(9 Council Houses, CW5 8AP) is F33, not the stale D67 — our computed 34.0
was right within a point; deal 499617935574 (Brightholme, 14 North Road)
is the accredited E43, not the preliminary 53. 58 Hackle Street (D58) and
16 Bingley Close (E52) were confirmed correct, so our +7.8/+5.7 deviations
there are extraction bugs to hunt next. Harness MAE 1.684 -> 1.551; ceiling
ratcheted to 1.56.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The extractor now captures "Heating System (Other):" and the mapper resolves
it to the Table 4a code (301, community boilers) + Table 12 community fuel
(51 via the shared _resolve_community_heating_fuel_code), so
is_heat_network_main routes the DLF / standing-charge / 80%-efficiency
branch instead of pricing the dwelling as an ordinary mains-gas boiler
(fixture 507644414148: +14.3 over-rate closes by ~8.6). Harness MAE
1.726 -> 1.684; ceiling ratcheted to 1.70.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Two dig-confirmed defects in the fresh RIR mapping (499617935574 overshot
-9): the roof-space-level insulation (Joists/200mm) was never threaded into
the RIR surfaces, so slopes/commons/flat ceilings fell to the Table 18
"unknown" full-uninsulated 2.30 default; and common walls were mislabeled
"common_wall" (a Simplified-Type-2-only concept) instead of the Detailed-mode
stud_wall every worksheet-validated fixture uses. 44.0 -> ~50.3 on the target
fixture; harness MAE 1.748 -> 1.726.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
_parse_room_in_roof captures the RdSAP §3.10 block (age range, floor area,
gables with Exposed/Party type, slopes, common walls, flat ceiling as
length x height) on main and extension roof spaces; both part builders now
carry it to sap_room_in_roof (issue #1590 bug 5 — closes the last #1590
subtask). Harness MAE 1.748 (754917 corrects to pashub's own pre-SAP; RIR
surfaces now billed per-surface instead of as insulated loft).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
_pashub_room_in_roof mirrors _api_build_room_in_roof: every surveyed RIR
surface (gable typed Exposed/Party per Table 4, slopes, common walls, flat
ceiling) becomes a detailed_surfaces entry of length x height, so the
cascade bills exact RIR surfaces instead of treating the shell as
well-insulated loft (issue #1590 bug 5).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
PasHub surveys never lodge a basement wall, but "System Build (i.e Any
Other)" maps to wall code 6 — the gov-API basement sentinel — and with
wall_is_basement left None the dwelling silently routed through the basement
wall/floor U-value cascade (issue #1590 bug 7). Both part builders now pin
the flag False. Harness MAE 1.732 -> 1.727.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
"Normal (90-130 litres)"->2, "Large (>170 litres)"->4; "No Access" follows
RdSAP 10 Table 28 p.55 (otherwise-branch 110L for a main-fed cylinder;
electric-immersion No Access strict-raises until meter context is plumbed).
The raw band string was int-or-noned by _cylinder_volume_l_from_code, skipping
the Table 28 volume convention (issue #1590 bug 6). Golden block updated.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
