Tithi (Lunar Day) Calculation — Perimeter×9÷30

The Varanasi Panchanga tradition classifies building Tithis into Nanda/Bhadra/Jaya/Rikta/Purna groups — a five-fold lunar taxonomy unique to North Indian practice. Bihar Sthapatis maintain Tithi-phala tables that prescribe specific Devata (deity) worship for each of the 30 possible Tithi results.

Peshwa-era Pune maintained court Jyotishis who verified building Tithis for all state construction — their records show that Wada foundations were adjusted by 2-3 cm when the initial perimeter yielded Amavasya or Rikta Tithis. The Maharashtrian Ekadashi observance tradition gives special weight to the 11th Tithi for domestic dwellings.

Tamil Sthapatis of the Vishwakarma community cross-reference the building Tithi with the Panchangam's Karana (half-Tithi) subdivision for temple construction — a double-precision lunar check found in no other tradition. Kumbakonam temple records show that the presiding deity's mythological Tithi determined the target remainder for the building's perimeter calculation.

Kakatiya guild record stones at Warangal contain Tithi remainder values carved alongside the other five Ayadi results — the oldest physical evidence of building Tithi calculations. Telugu tradition gives special significance to Ugadi Tithi (Chaitra Shukla Pratipada) and considers a building whose remainder maps to Pratipada (1st Tithi) to be blessed with new beginnings.

Jain Basadis at Mudabidri contain inscribed Tithi values alongside the other Ayadi remainders on pillar bases — a permanent mathematical certificate of the building's lunar alignment. The Jain astronomical tradition (Surya-prajnapti) provides independent Tithi tables that Hoysala Sthapatis cross-referenced with the Vedic Panchangam for verification.

The Perumthachan lineage prescribes that the Thachan announce the building's ruling Tithi aloud at the Bhoomi Puja — the householder must verbally accept it as part of a cosmic-verbal contract. Kerala's Vaishnava tradition gives Ekadashi (11th Tithi) special architectural significance, considering it the most auspicious lunar day for Nalukettu construction.

Solanki-era Havelis in Patan contain Tithi values inscribed on the courtyard foundation alongside other Ayadi remainders — visible proof that the lunar-day calculation was performed. The Gujarati Jain tradition treats Purnima Tithi as especially auspicious due to its association with Mahavir Jayanti and Paryushana observances.

Bengali Sutradhar guilds cross-reference the building Tithi with the Panjika's festival calendar — a building whose Tithi maps to Dashami (Vijaya Dashami, Durga's victory day) is considered especially fortunate. The dual Ganaka-Purohit announcement at the Bhoomi Puja includes the Tithi as part of a six-fold mathematical-ritual validation unique to Bengal.

The Jagannath Temple at Puri is traditionally cited as yielding a Purnima (full moon) Tithi remainder — considered the supreme lunar alignment. Kalinga tradition gives special significance to Dvitiya (2nd Tithi, Rath Yatra day) and Ekadashi (11th) for residential buildings, reflecting the region's strong Jagannath Vaishnava culture.

Punjabi Raj-Mistri guilds cross-reference the building Tithi with both the Nanakshahi calendar and the Vedic Panchanga — a dual-calendar verification unique to Sikh practice. Sangrand (first day of each Nanakshahi month) Tithis are considered especially auspicious for building foundations, reflecting the Sikh emphasis on new beginnings aligned with Hukam.