Where does a new home's price go, and which levers move it most?

What it found

A driver-based price model anchored on NAHB's 2024 cost shares (construction 64.4% of the price, framing 16.6% of construction, lot 13.7%, profit 11.0%). Each construction stage scales with floor area, footprint or wall area, and the model reproduces every NAHB share at its 2,000 sq ft reference house. In a sweep, size moves the price most (index 87.8 to 112.0 for 1,600 to 2,400 sq ft), then one against three storeys (111.6 to 97.6), finish level, lot price and foundation type. A 14% cut in framing lumber, the gap between house-plan's default and best plans, is worth only 0.85% of the price, or 2.4% if it also cuts framing labour by 20%. Stylised: a price index, not dollars; the stage-driver splits and lever ranges are my assumptions; the Census reconciliation and a priced takeoff are not done.

A figure from its own output

Paper, code and results

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

More in Open-source residential construction

• Does the house-cost lever ranking survive its assumed driver splits?Does the house-cost lever ranking survive its assumed driver splits? Monte Carlo over the splits: floor area stays the largest lever in 96–100% of draws; storeys is the soft claim (swing 9.0–19.9 vs 14.0 baseline); the lumber result does not move. Index not dollars.
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• Does any alternative to a wood-framed wall beat it on cost, carbon or heat loss for a small house?Does any alternative to a wood-framed wall beat it on cost, carbon or heat loss for a small house? In a stylised model wood 2x6 is cheapest in 97% of random draws and lowest-carbon in 100%; SIP, CLT and printed walls win only on labour. Inputs are ranges from memory.
• Does a small wood-frame house have enough shear wall for wind and earthquakes once the windows and doors are cut out?Does a small wood-frame house have enough shear wall for wind and earthquakes once the openings are cut out? At 115 mph and SDS 0.50 the 28 x 40 ft house uses 19% of a gable-wall line's capacity at 6 in nailing; the openings, not the load, are what shrink it. Stylised, capacities from memory.
• How much does accidental torsion add to the garage-front wall's demand in a rigid-diaphragm wind split?How much does accidental torsion add to the garage-front wall's demand in a rigid-diaphragm wind split? Offsetting the load up to 15% of the length in house-nailedwall's split raises a 22 ft-door wall from 0.36–0.59 to 0.44–0.71 demand over capacity, still under the flexible 1.05. Stylised.

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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.