SampleHouse Analysis — SampleHouse Guardrails¶

Foundation: BBC · DATA_MODEL · BIM_COBOL · MANIFESTO · TestArchitecture

Stone: 1 of 3 (smallest — hello-world proof) Updated: 2026-03-28 (S100-p85 fleet audit recompilation)

Building Identity¶

Property	Value
Name	SampleHouse
IFC version	IFC4 (single file)
Country	N/A (reference building)
Type	Single-storey residential
Elements	58
Disciplines	3 (ARC: 35, STR: 20, CW: 3)
M_Product_Category	RE (Residential)
Prefix	SH
C_DocType_ID	RE_SH
Reference DB	`DAGCompiler/lib/input/SampleHouse_extracted.db`
BOM DB	`library/SH_BOM.db`

Discipline Breakdown (verified against component_library.db)¶

Discipline	Count	Elements
ARC	35	Walls, doors, windows, furniture, slabs, coverings
STR	20	Slabs, walls (structural)
CW	3	Cold water pipes
Total	58

Key Settings¶

Setting	Value	Source
Compilation mode	EN-BLOC (singularity)	BBC.md §3.3
BOM tree shape	Self-describing (BBC.md §1): BUILDING → FLOOR → ROOM → SET → LEAF for SH	RE pattern
Origin convention	BUILDING has world LBD; FLOOR/ROOM zeroed (R16)	BBC.md §4.1
YAML	`classify_sh.yaml`	Single storey, 5 rooms
Mirror	None (single unit)	—
Scope spaces	`floor_rooms:` IFC space → BOM template mapping	classify_sh.yaml

Gate Status¶

Gate	Status	Value
G1-COUNT	PASS	58
G2-VOLUME	PASS	+0.00%
G3-DIGEST	PASS	496022db
G4-TAMPER	PASS	0 violations / 20 rules
G5-PROVENANCE	PASS	7 checks
G6-ISOLATION	PASS	—

Recompilation (S100-p85 Fleet Audit, 2026-03-28)¶

BOM walk recompilation via CompileStage → writeFromBomWalk(). 7/7 PASS.

Metric	Value
Elements	58 (was 55 — 3 additional from CW discipline)
Root BOM	BUILDING_SH_STD, origin=(-9.235, -2.746, -0.470)
Verbs	22 PLACE, 4 CLUSTER
Disciplines	ARC=24, STR=2, CW=2
LOD binding	58 LOD, 0 fallback, 0 missing
H6 WARNs	24 (MEP schedule vs actual — no MEP elements yet)

LMP Drift Check: 6 pass, 0 fail, 2 deferred

§	Check	Verdict
§1	Input=Output	PASS (58/58)
§2	LOD400	PASS (58/58 OK, 0 warn, 0 fail)
§3	Compiler Only	PASS (T18/T19/T20 guard)
§6	Output Path	PASS (single path)
§7	Separate From Input	PASS (bom.db=library/_SH_compile.db)
§8	Visual Fidelity	PASS (geometry OK)
§4	Openings	deferred (no proof aggregate)
§9	Orientation	deferred (no proof aggregate)

BOM Compilation Model (S147)¶

The Sample House is the simplest Rosetta Stone — 58 elements, no mirroring, single storey + roof. It proves the BOM compilation concept in its purest form.

BUILDING_SH_STD (BUILDING)                     ← the order: "build this house"
 ├─ SH_GF_STR (FLOOR)       13 → 16 instances ← ground floor structure (walls, slabs)
 │                                               verbs: TILE (curtain wall mullions)
 ├─ SH_RO_STR (FLOOR)        2 → 2 instances  ← roof structure
 ├─ SH_UN_STR (FLOOR)        2 → 2 instances  ← unknown storey (2 beams)
 ├─ SH_ROOM_GF (FLOOR)       2 rooms          ← room index
 │   ├─ SH_1_LIVING_ROOM_SET (SET)  9 → 12    ← living room: sofa, table, chairs, piano
 │   │                                           verb: CLUSTER (chair group)
 │   └─ SH_2_BEDROOM_SET (SET)      2 → 2     ← bedroom: bed, wardrobe
 ├─ FLOOR_SLAB_GF (ASSEMBLY) 0                 ← ground slab (stub)
 ├─ ROOF_ASSEMBLY (ASSEMBLY)  0                 ← roof assembly (stub)
 ├─ SH_UN_ASM_1 (ASSEMBLY)  13 → 13           ← assembly: windows, doors
 └─ SH_UN_ASM_2 (ASSEMBLY)   7 → 13           ← assembly: coverings, verbs expand

11 BOMs, 56 lines, 58 instances. Almost 1:1 — minimal factorization because SH has few repeated elements. The living room chair CLUSTER (3 chairs at explicit offsets) is the only verb-expanded group.

No mirroring, no rotation. SH is a simple box — IDENTITY transform on every element. This makes it the baseline: if SH breaks, the core BOM walk is broken. If SH passes but DX fails, the issue is in the mirroring/rotation layer.

SPATIAL-REPORT: outliers=4 sym=4 asym=0 — 4 IfcMember (rafters) with stepped X offsets. These are real position differences from the LOD placement vs IFC reference, not compilation errors.

Logging proof: grep BOM-SUMMARY logs/*SampleHouse*ifctobom*.log shows this tree. grep SPATIAL-REPORT logs/pipeline_SH*.log for spatial accuracy.

Guardrails¶

Smallest stone — any regression shows here first. Run SH before DX/TE.
BOM walk path — single compilation path for all buildings (S100-p72).
TRIM verb active — glass curtain wall panels trimmed to the pitched roof intersection. SH now uses 22 PLACE + 4 CLUSTER verbs. CLUSTER factorizes windows.
ProveStage skipped — no relational data (§4, §9 deferred).

Known Issues¶

H6 WARNs (24): MEP schedule expects products in rooms but no MEP elements compiled yet. These are advisory findings in LOG mode — will resolve when discipline recipes produce elements.
ProveStage 0ms: Prover skipped for all non-relational buildings. Not SH-specific.

SH is the hello-world proof. If SH breaks, nothing else can be trusted. See BOMBasedCompilation.md §3.3 (EN-BLOC = HelloWorld).