अरत्निरिन्द्रकीलः ॥ कZ_०२.३.२६ ॥
aratnirindrakīlaḥ
Indrakīla (pasak tanah/pin pengunci) harus sepanjang satu aratni (ukuran satu lengan bawah).
It prevents under-building (cost-cutting that weakens security/stability) and makes compliance measurable during inspection.