Matsya Purana — Śarkarā-Saptamī Vrata: The Sugar Offering Rite to Savitṛ
सर्वोपस्करसंयुक्तं तथैकां गां पयस्विनीम् गृहं च शक्तिमान्दद्यात् समस्तोपस्करान्वितम् //
sarvopaskarasaṃyuktaṃ tathaikāṃ gāṃ payasvinīm gṛhaṃ ca śaktimāndadyāt samastopaskarānvitam //
A capable person should donate a house furnished with all necessities, and also give a single milch-cow; the house should be endowed with complete household equipment.
This verse does not address Pralaya; it is a Dharma instruction focused on meritorious charity (dāna), specifically gifting a furnished house and a milch-cow.
It frames an ideal act of generosity for those with means—supporting social welfare by providing shelter (gṛha-dāna) and sustenance (go-dāna). Such gifts are presented as righteous conduct for householders and rulers alike.
The architectural element is practical rather than technical Vāstu: the gift is a functional dwelling “with all implements,” implying a complete, usable home as part of ritualized charity.