Inputs
Use measured 延床 (GFA). Typical JP detached house is 90–140 m².
All numbers are planning estimates. Get quotes from licensed 建設業者. Toggle items and change unit costs below.
Estimate
Base construction
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Add‑ons & systems
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Soft costs (design/permits)
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Contingency
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| Component | Unit cost | Qty | Line total (JPY) |
|---|---|---|---|
| Subtotal (hard + add‑ons) | – | ||
| Soft costs (design/permits) | – | ||
| FF&E / Furnishings | – | ||
| Misc. approvals | – | ||
| Contingency | – | ||
| Total (JPY) | – | ||
| Total (USD) | – | ||
Click a unit‑cost cell to override it inline. All calculations run locally in your browser.
Unit‑Cost Assumptions
Defaults reflect recent bids for residential renovations (rural→metro). Adjust to your contractor, condition, and goals.
Restore defaults
| Item | JPY per m² or fixed |
|---|