Does a factory-built shell pay once the interest on the days it saves is counted?

What it found

Joins house-offsite's extra cost of panelising the walls ($1,373 at assumed rates) to house-schedule's interest on working days saved, comparing a factory shell with a site-built house ordered on the same day. The shell alone saves 15.5 days (0.22% of price at 8%) when ordered at day 0 and only 6.4 days when ordered at the foundation start with a 25-day lead; it breaks even at a house price of about $629,000 at a $1,500 crane day and pays throughout at $750. Most of house-schedule's 78-day saving is the ordering date, not the shell. Stylised: house prices are parameters and every rate is assumed.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
• Tests

More in Open-source residential construction

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All 41 Open-source residential construction projects →

Other research topics

Proper scoring & elicitation28Effort & peer prediction9Verification games & slashing19Detection & tolerances14Markets as routers13Prediction-market design9Paying contributors8Decentralised training systems23Digital twins & sim-to-real164LLM chip design loops40Robot manufacturing loops53Ambient AI assistant46Self-replicating manufacturing34Simulation-first design64Engineered clothing45Task-specific AI accelerators40Algorithmic chip-design loops42Open-source purpose-built robots44The software-engineering loop43Adversarial human imitation41Open-source residential construction41Autonomous multi-angle capture34Sensing, imaging and 3D31Energy supply and dense energy storage39Robot societies among people31Agentic co-design of low-cost robots27Laundry-hanging robots25Machine learning on qualitative data23Robots on the building site27Civilizations & group psychology1History & human sciences1

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.