# description
Open-source BIM data format for permit-grade audit + Hamada method. Optimized for small-medium residential / school / civic buildings. MIT licensed. https://bim.house/spec

# properties.spec_version.description
Semantic version of the μBIM spec this file conforms to (1.x.y).

# properties.elements.description
Building elements (walls, slabs, windows, etc.).

# properties.audit.description
Auto-generated by houki engine; user code should not write here directly.

# properties.signatures.description
Architect / engineer signatures over the canonical JSON (excluding this field). Verified via Ed25519.

# $defs.Element.properties.rotation.description
Rotation around Z axis in radians (right-hand rule).

# $defs.Material.properties.f_star.description
Sick House F☆ grade (F4=F☆☆☆☆, lowest VOC)

# $defs.Signature.properties.scope.description
Legal/responsibility scope of this signature

# $defs.Signature.properties.digest.description
Hex-encoded hash of canonical JSON (RFC 8785) excluding this signatures field

# $defs.Signature.properties.signature.description
Base64-encoded signature over the digest