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IECC commercial prototypes

Release 1.3.0 adds the IECC commercial prototype family: the 16 PNNL building types in the IECC 2006, 2009, 2012, 2015, 2018 and 2021 editions, 96 folders under commercial/iecc-<year>/<building-type>/. The decision record is ADR 0040; the release notes are docs/release-notes-atlas-v1.3.0.md.

The family is separate from ASHRAE 90.1. No IECC edition is paired with a 90.1 edition, and no record is shared. An evidence-only comparison is in docs/reviews/iecc-commercial-vs-90-1.md.

Where the values come from

  • Source: the pinned PNNL IECC IDFs (EnergyPlus 22.1), one per climate zone from 0A to 8. They are extracted offline into data/program-inputs/iecc-commercial-<year>.json by scripts.iecc_commercial_values, so the release builds without the 4.6 GB of archives.
  • Space types: the IDFs have no spaces. A zone takes the standards space type of the same-named space in the openstudio-standards 90.1 geometry, through one lookup table. Where the 90.1 geometries tag a name differently, the 90.1-2019 tag applies; each such name is listed with its reason in sources/iecc-commercial-zone-aliases.json.
  • Programs: one per space type, area-weighted over its zones with their multipliers. The IDFs are complete models, so an absent object is a source zero.
  • Type names: atlas names (MediumOffice, not OfficeMedium); the PNNL name is kept as pnnl_building_type.
  • Mixes: the composition-policy recipes of the same building type, weighted by IDF zone floor area times multiplier.

Values that differ by climate

Loads are mostly the same in all 19 locations of an edition. Where one differs, mostly IECC 2021 lighting, value holds the most common value and value_by_climate the others, for example {"0B": 6.59, "1B": 6.59} for the 2021 medium office (Program JSON 5.2.0). Zones 7 and 8 have no moisture regime in the source; the atlas labels them 7A and 8A and keys their construction contexts 7-a and 8-a.

IECC programs export in the source version only. They hold source values with no fillings, and the filled version's water-heating fold needs source water heaters, which are deferred with the systems.

Constructions

  • Sets: one per folder, with 19 contexts, from the IDF constructions and materials (detailed construction JSON 4.2.0 when added; 5.0.0 in release 2.4.0).
  • Assignments: where a component varies, by story position (ground, middle, top) and space type. Surfaces no rule explains keep surface-level assignments.
  • Infiltration: the IDF design-flow rules per zone, with their schedules inline, as the source_design_flow method. There is no natural-ACH value.
  • Window ratios: the 15 whole-building values are on the set; programs carry their own by direction.
  • Unified representation: from release 1.6.0 (ADR 0045). Each context holds a building-level equivalent weighted by the net surface areas of its IDF; --representation unified exports it as construction-equivalent 3.1.0. Release 1.3.0 to 1.5.0 refuse it.

Services and water

  • Building services: elevators, reach-in refrigeration, exhaust fans, exterior lights and equipment, and refrigeration cases and racks.
  • Hot-water draws: they keep their zones and EnergyPlus gain fractions.
  • Out of scope: HVAC, plant and water heaters, as for the DOE reconciliation.