### Design
#### Building Configuration (3-Story Module)
- 45 residents total (15 per floor)
- Footprint: 4,300 sq ft per floor
- Total area: 12,900 sq ft
- Height: 36 ft (12 ft per floor)
- Roof area: 4,300 sq ft usable for solar/thermal
#### Energy Systems Integration
##### Solar PV System
- Required capacity: 75 kW (5 kWh/day × 45 residents ÷ 3 hours equivalent full sun)
- Roof area needed: 3,000 sq ft (75 kW × 40 sq ft/kW)
- Available roof: 4,300 sq ft (adequate with space for thermal)
- Annual generation: 82,125 kWh (75 kW × 1,095 kWh/kW/year)
- System cost: $150,000 ($2/W installed)
- Lifespan: 25 years
- Annual maintenance: 40 hours, $500
##### Solar Thermal System
- Collection area: 900 sq ft
- Peak capacity: 45 kW thermal
- Storage: 2,000 gallons
- System cost: $90,000
- Lifespan: 30 years
- Annual maintenance: 30 hours, $400
### Lifespan-Based Cost Analysis
*Per person costs based on 45 residents*
| cost | dollars | hours |
| -------------------------------- | ------- | ----- |
| amortized initial building costs | $1264 | 4.37 |
| annual maintenance | $269 | 13.3 |
| **Total** | $1533 | 17.67 |
#### Amortized Initial Building Costs
| Component | Initial Cost ($/hrs) | Lifespan | Annual Cost ($/hrs) | Per Person ($/hrs) | Notes |
| ------------------ | -------------------- | -------- | ------------------- | ------------------ | --------------------------------------- |
| Foundation | $125,000/480 | 75 | $1,667/6.4 | $37/0.14 | Forms, rebar, concrete, waterproofing |
| Structural Frame | $250,000/960 | 75 | $3,333/12.8 | $74/0.28 | Engineered wood frame, decking, bracing |
| Walls & Insulation | $245,000/1,200 | 40 | $6,125/30 | $136/0.67 | High-performance assembly, air sealing |
| Main Electrical | $85,000/320 | 30 | $2,833/10.7 | $63/0.24 | Distribution, panels, safety systems |
| Rainwater System | $30,000/160 | 30 | $1,000/5.3 | $22/0.12 | Collection, filtration, storage |
| Drainage Systems | $35,000/240 | 30 | $1,167/8 | $26/0.18 | Site drainage, piping networks |
| Windows & Doors | $175,000/320 | 25 | $7,000/12.8 | $156/0.28 | Triple-pane windows, insulated doors |
| Roofing | $125,000/280 | 20 | $6,250/14 | $139/0.31 | Membrane roofing, insulation |
| Mini-Split HVAC | $85,000/240 | 15 | $5,667/16 | $126/0.36 | Heat pumps, distribution |
| Solar PV | $150,000/200 | 25 | $6,000/8 | $133/0.18 | 75kW system, inverters |
| Well & Pump | $25,000/80 | 15 | $1,667/5.3 | $37/0.12 | Well drilling, pump system |
| ERV System | $15,000/120 | 15 | $1,000/8 | $22/0.18 | Ventilation, heat recovery |
| Compost System | $45,000/160 | 20 | $2,250/8 | $50/0.18 | Collection, processing |
| Greywater System | $25,000/120 | 15 | $1,667/8 | $37/0.18 | Treatment, distribution |
| Lighting | $45,000/200 | 15 | $3,000/13.3 | $67/0.30 | LED fixtures, controls |
| Flooring | $45,000/240 | 15 | $3,000/16 | $67/0.36 | Durable materials |
| Cabinetry | $65,000/280 | 20 | $3,250/14 | $72/0.31 | Built-in storage |
| **TOTAL** | **$1,570,000/5,600** | - | **$56,876/196.6** | **$1,264/4.37** | |
#### Annual Maintenance Costs
| System | Material Cost | Hours | Per Person Cost | Per Person Hours |
|--------|--------------|-------|-----------------|------------------|
| HVAC & ERV | $1,800 | 64 | $40 | 1.4 |
| Water Systems | $1,300 | 52 | $29 | 1.2 |
| Composting/Greywater | $3,200 | 208 | $71 | 4.6 |
| Solar & Electrical | $800 | 24 | $18 | 0.5 |
| Building Envelope | $1,800 | 52 | $40 | 1.2 |
| Interior Finishes | $1,500 | 52 | $33 | 1.2 |
| Structure & Site | $1,700 | 144 | $38 | 3.2 |
**Annual Per Person Maintenance: $269 and 13.3 hours**