Model/domain
Khalim Conn-Kowlessar 4fb9b853dc fix(ventilation): apply Table 4g note 3 in-use factor to index-less MEV SFP
The no-PCDB MEV fan-electricity path fed the SAP 10.2 Table 4g default SFP
(0.8 W/(l/s)) directly as SFPav. But Table 4g note 3 (PDF p.176) is explicit:
the default SFP values "are to be multiplied by the appropriate in-use factor
for default data from the PCDB" — PCDB Table 329 system_type 10 ("default
data, used when SFP is taken from Table 4g rather than the PCDB"), IUF 2.5
(duct-agnostic per note 2). Table 4h, which previously held these factors, is
retired ("no longer used – data now stored in the PCDB").

Omitting the IUF under-billed the index-less MEV fan electricity by 2.5x
(SFPav 0.8 instead of 0.8 x 2.5 = 2.0), so cost was too low and the cohort
over-rated. This is distinct from the with-index path, which already applies
the tested-product system_type-2 "no scheme" IUF (~1.45) per fan.

Index-less gas-house MEV cohort: +1.37 median -> -0.18 (12% -> 92% within 0.5),
no overshoot — the missing IUF was exactly the over-rate. API gauge 67.7% ->
68.4% within-0.5 (mean|err| 0.992 -> 0.986, signed +0.031 -> +0.006).
Worksheet harness 47/47, 0 divergers (Summary-path MEV certs carry a PCDB
index or are natural, so unaffected).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-13 23:15:32 +00:00
..
addresses standardist Address 2026-05-22 10:13:32 +00:00
billing feat(modelling): attribute per-measure bill savings via a telescoping cascade 2026-06-03 18:01:11 +00:00
data_transformation moved classifier data transformation to an easy one 2026-06-01 14:53:34 +00:00
epc Remove EPC and asset_list changes unrelated to SAL handler 2026-06-01 16:39:09 +00:00
fuel_rates feat(fuel-rates): FuelRates snapshot + repository foundation (ADR-0014) 2026-06-02 09:29:07 +00:00
geospatial feat(geospatial): one-read spatial reference (coords + restrictions) 2026-06-04 17:13:39 +00:00
magicplan add todo comment for named ranges 2026-06-10 13:32:11 +00:00
modelling feat(modelling): cost data for secondary-heating-removal (ADR-0028) 2026-06-11 13:51:16 +00:00
property feat(modelling): thread Property planning restrictions to the solid-wall gate 2026-06-04 16:32:26 +00:00
property_baseline feat(baseline): sap_code_to_fuel normalizes via the calculator's own helper 2026-06-05 18:59:25 +00:00
sap10_calculator fix(ventilation): apply Table 4g note 3 in-use factor to index-less MEV SFP 2026-06-13 23:15:32 +00:00
sap10_ml Merge remote-tracking branch 'origin/main' into feature/per-cert-mapper-validation 2026-06-13 22:20:15 +00:00
tasks added postcode splitter rewrite to ddd 2026-05-19 16:35:09 +00:00
building_geometry.py feat(modelling): floor Recommendation Generator + ground-floor-area geometry 2026-06-03 09:12:29 +00:00
postcode.py get rid of comments 2026-05-20 13:21:11 +00:00