Build Time
Build Time to 1.0 Labor-Hour per Square Foot
This page defines how Open Source Ecology (OSE) can credibly achieve approximately 1.0 all-in labor-hour per finished square foot (LH/ft²) for housing construction. This is not a productivity claim but a systems-design outcome based on structural elimination of labor categories.
Canonical Metric Definition
OSE uses a single, non-negotiable metric:
All-in Labor Hours per Finished Square Foot (LH/ft²)
This includes every human labor hour required to deliver a finished, inspected, code-compliant house, excluding land acquisition.
Included:
- On-site and off-site fabrication
- Logistics and material handling
- Staging and setup
- Coordination and supervision
- Inspections and rework
- Training inefficiency
- Tooling setup
- Punch lists and callbacks
Any metric that excludes these categories is not acceptable for system planning.
Industry Baseline
Conventional housing typically exhibits the following labor distribution:
| Category | Typical LH/ft² |
|---|---|
| Direct build labor | ~0.85 |
| Trade handoffs and waiting | 0.40–0.60 |
| Inspection friction | 0.20–0.30 |
| Rework and errors | 0.30–0.50 |
| Coordination and supervision | 0.30–0.50 |
| Logistics and staging | 0.20–0.30 |
| Training and variability | 0.20–0.30 |
| Total | ~2.5–3.0 |
OSE’s objective is to remove approximately 1.5–2.0 LH/ft² by eliminating entire labor categories rather than compressing them.
Principle: Labor Is Eliminated, Not Optimized
OSE does not pursue 1.0 LH/ft² through:
- Increased effort
- Better management
- Higher skill
- Motivation
- Lean terminology
OSE achieves 1.0 LH/ft² by making entire classes of labor disappear structurally.
Elimination Strategy
Eliminate Trade Boundaries
Target reduction: 0.4–0.6 LH/ft²
Rule: No build step may require waiting for another trade.
Mechanism:
- Multi-trade modules (structure, wiring, boxes, air sealing combined)
- No rough-in versus finish phases
- No return visits
OSE action: Walls, floors, roofs, wet cores, and power centers are treated as atomic modules that are completed once, fully.
If a worker must return later, the design has failed.
Eliminate Inspection Labor
Target reduction: 0.2–0.3 LH/ft²
Inspections compensate for low process trust.
Mechanism:
- Fixed module designs
- Fixed fastener schedules
- Fixed routing paths
- Process verification instead of outcome investigation
OSE action: Modules are pre-approved. Inspectors verify that the approved process was followed, supported by time-lapse and AI-assisted quality control artifacts.
This model is legally established in modular construction.
Eliminate Rework
Target reduction: 0.3–0.5 LH/ft²
Rework is caused by ambiguity and field decisions.
Mechanism:
- No field interpretation
- No dimensional freedom
- No undocumented decisions
OSE action: CAD-for-swarm is a first-class production output. Every module includes:
- Defined ports
- Datum references
- Tolerance envelopes
If CAD does not exist, the module does not exist.
Eliminate Coordination Overhead
Target reduction: 0.3–0.5 LH/ft²
Coordination exists due to human-dependent sequencing.
Mechanism:
- Self-sequencing modules
- Geometry-enforced order
- Error-proofing
OSE action: Assembly order is encoded in geometry. Modules cannot be installed incorrectly. If explanation is required, the system has failed.
Eliminate Training Drag
Target reduction: 0.2–0.3 LH/ft²
Training drag is driven by variance, not skill.
Mechanism:
- Short, repeatable task units
- Binary quality checks
- Visual instruction dominance
OSE action: Tasks are designed for 15–30 minute execution windows. Workers execute protocols rather than learning trades.
Physics-Limited Residual Labor
After eliminations, remaining labor approaches the physical floor:
| Category | LH/ft² |
|---|---|
| Physical assembly | 0.75–0.85 |
| Logistics (irreducible) | ~0.10 |
| Oversight | ~0.05 |
| Residual friction | ~0.05 |
| Total | ~0.95–1.05 |
This is achievable without heavy robotics.
Why OSE Can Achieve This
Commercial builders cannot reach this threshold due to:
- Fragmented incentives
- Trade silos
- IP enclosure
- Adversarial contracting
- Liability partitioning
OSE can achieve this because:
- Unified design authority
- Open CAD and documentation
- Integrated training and production
- Elimination of trade monopolies
This is an institutional architecture advantage, not a technology advantage.
Required Precursor Deliverables
OSE must build the following before house-level optimization:
- Canonical module library
- CAD-for-swarm standards
- Time-lapse and AI quality control pipeline
- Module-level labor benchmarks
- Inspection pre-approval agreements
Only after these exist can house-level labor collapse toward 1.0 LH/ft².
Bottom Line
Achieving 1.0 LH/ft² is feasible and defensible. It is not optimistic and not a productivity claim. It is the outcome of correct system design.
OSE succeeds by refusing to allow labor to exist where information should exist instead.