Skip to main content

koyu site

Gives site area, road frontage, building coverage ratio and floor area ratio. They are derived from the composition rather than declared — the volume-study numbers of schematic design.

Arguments​

koyu site <entry.muro>

Takes one entry path.

Flags​

None.

The two declarations it needs​

ElementHow it is written
The siteA zone carrying site:1
A roadAn exterior space carrying road:<width in mm>

Without both, no site report comes out.

Output​

npx tsx src/cli.ts site examples/house/main.muro
Site /site (敷地)
  Site area: declared 126.24 m2 / derived 126.24 m2
  Road: /out/road (南側道路) width 6000mm / frontage 10280mm
  Building footprint (horizontal projection, rough): 53.00 m2 → building coverage ratio 42.0%
  Total floor area: 92.75 m2 → floor area ratio 73.5%
LineContents
SiteThe site zone's path and display name
Site shapeOnly when a polygon is declared. The vertex count
Site areaBoth figures as declared … / derived … when area: is written; otherwise one figure as Site area (derived):
RoadOne line per road: width and frontage
Building footprintBuilding footprint (horizontal projection, rough) and coverage ratio
Total floor areaTotal floor area and floor area ratio

The denominator of the ratios is the declared value when area: is written, and the derived value otherwise.

When the site shape is declared​

Writing the site shape as a polygon makes the area come from that polygon. The reconciliation against the zone's area: (the surveyed figure) is simply the two numbers side by side.

npx tsx src/cli.ts site examples/tower/main.muro
Site /site (敷地)
  Site shape: polygon with 5 vertices (a polygon declaration — given geometry)
  Site area: declared 1097.80 m2 / derived 1097.80 m2
  Road: /out/road-s (南側道路) width 12000mm / frontage 40600mm
  Road: /out/road-e (東側道路) width 6000mm / frontage 20200mm
  Building footprint (horizontal projection, rough): 569.60 m2 → building coverage ratio 51.9%
  Total floor area: 4785.92 m2 → floor area ratio 436.0%

When the declared and derived figures disagree, site silently prints both. Calling the disagreement a problem is koyu validate's site.area (caution). A building that leaves the site polygon is site.escape (violation); frontage under 2m is site.frontage (violation).

How frontage is counted​

Frontage is the total length of the boundary segments between spaces under the site zone and the road. A building wall that faces the road directly is not counted. Write only the building and no exterior works, and the frontage comes out as zero.

When there is no site​

npx tsx src/cli.ts site examples/mansion.muro
There is no site (write site:1 on a zone and road:<width> on the road)

Exit codes​

Exit codeMeaning
0The site report came out
1There is no site (no zone with site:1 and no exterior with road:), or the input could not be read
2No file path was given (usage is printed)

site only produces numbers; it never passes judgement. Whether a coverage ratio of 51.9% exceeds the permitted figure is not information this surface holds.

About the coarseness​

The rules for what counts toward the building footprint are rough. Overhangs, the treatment of basements and garage relief are all ignored. Total floor area is the same figure as koyu stats's indoor floor area, so semi-outdoor and outdoor are not in it.

See also​