How much do fewer handoffs, parallel trades, early ordering and a factory shell cut the time to build a house?
research/house-schedule
How much do fewer handoffs, parallel trades, early ordering and a factory shell cut a house's build time? Discrete-event Monte Carlo: critical path 100 working days, baseline 214; early ordering -63 d, fewer handoffs -21, a factory shell only -6 unless ordered at day 0 (-78). Stylised, uncalibrated.
What it found
A Monte Carlo discrete-event model of one house build (20 tasks, a crew per trade, failing inspections, weather, material lead times; 4,000 builds per scenario with common random numbers). The zero-noise critical path is 100 working days but the baseline takes 214: the schedule is driven by waiting. Ordering long-lead materials at day 0 saves 63 days, fewer handoffs 21, parallel rough-in 12.5, faster inspections 11. A factory wall-and-roof shell saves only 6 days if ordered when the foundation starts and 78 if ordered at day 0. All levers together: 96 days, about 1.7% of the price in interest at 8%. Stylised: every duration and rate is my assumption and nothing is calibrated; the 63-day figure rests on a late-ordering baseline.
A figure from its own output
Paper, code and results
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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.