KomBo — Oslo kommunes eiendommer på kart

KomBo (fra «kommunale boliger») — navnet stammer fra boligfokuset, men kartet viser i dag alle fire kommunale etater (EBY, Oslobygg, Boligbygg, Havn).

An interactive Leaflet map of every property Oslo kommune owns — across all four municipal bodies: from rental housing to schools, from road parcels to the harbour. Live at https://kombo.ichiva.no/.

This repo is just the map (index.html). The data — downloading the kommune's spreadsheet, geocoding every parcel, and serving it — is produced and served by a separate service, kombo-api.

kombo-api  ──(HTTP)──>  index.html  ──>  map in browser

What's in scope

The source spreadsheet (re-published every six months by the kommune) lists every property the city owns — ~7,000 rows across four owning agencies:

Eier / fester	Antall	Rolle
Eiendoms- og byfornyelsesetaten	~5,621	Tomter og veiareal — kommunens største grunneier
Oslobygg KF	~795	Formålsbygg: skoler, barnehager, sykehjem, idrettsanlegg, kontorer
Boligbygg Oslo KF	~528	Kommunale utleieboliger
Oslo Havn KF	~78	Havnevirksomhet og eiendommer langs sjøsiden

Plus a toggleable layer of Oslo-owned land outside Oslo (Oslomarka forest + drinking-water catchment in ~20 neighbouring kommuner).

Data source

index.html fetches its dataset at boot from the kombo-api service:

• https://kombo-api.ichiva.no/features — the single source of truth (regenerated weekly).

If the API is unreachable, an embedded sample dataset renders with a banner so the page degrades gracefully. The data pipeline (XLSX → geocode → GeoJSON), the /nearby proximity endpoint, and the GeoJSON contract all live in kombo-api.

Run it

No build step, no dependencies — it's one static file:

python -m http.server 8000   # → http://localhost:8000/index.html

It fetches its data from the live API; if that's unreachable it shows an embedded sample with a banner.

The map (index.html)

Single file, no build step, CDN deps (Leaflet + markercluster + leaflet.heat + Tailwind Play CDN). Deployed automatically to GitHub Pages on every push to main.

Left sidebar — the kommune view:

• Punkter — clustered markers, coloured by owning agency. Cluster bubbles inherit the colour when all children share one owner; mixed clusters go neutral grey
• Tetthet — heat layer (where ownership clusters)
• Areal-vekt — heat weighted by parcel size (big sites glow brighter)
• Vis tomtegrenser — Kartverket Teig outlines styled per agency colour (cluster mode only — they fight the heat visualisation in the other modes)
• A "Lag" section toggles the two layers ("Eiendommer i Oslo" master gate + "Eiendommer utenfor Oslo"), then per-agency toggles, bydel filter (with live counts), basemap switch (CARTO Mørk / Lys / Esri Satellitt)
• "Topp bydeler" ranking — top 10 districts by parcel count in the current selection
• Popup links straight into Grunnboken/eiendomsregisteret for each parcel

A floating search bar (top-left, past the zoom controls) searches the whole dataset by address, matrikkel or bruksnavn and zooms straight to a hit.

Right sidebar — "Mine punkter" (sammenligning):

• Add a pin by typing an address (debounced Geonorge search) OR clicking "Klikk på kart" + clicking a spot OR right-clicking the map → "Legg til markør her"
• Each pin is auto-enriched: reverse-geocoded for address + matrikkel, then the parcel's Teig polygon is fetched from Kartverket and drawn in magenta around the pin
• Pin popup ranks the 25 nearest kommune parcels within 150 m, split into "Bygg" (Oslobygg / Boligbygg / Havn) and "Tomter / veiareal" (EBY). Distance measured to the closest tomtekant (default) or the address marker — toggle via "Avstand måles til"
• Hover a row to preview the measurement line; click to pin it (solid, labelled with distance, persists across reloads). Click the row again to unpin

Persistence:

• Selections, map centre/zoom, sidebar collapse state persist in localStorage (key kombo.v1); pins under a separate key (kombo.userPins.v1)
• Light/dark palette follows prefers-color-scheme; saved layer choice wins
• Responsive down to phone/tablet — the rails and search bar reflow on small screens (page-zoom is disabled so focusing a field doesn't auto-zoom)

Shareable URLs: the current view round-trips through location.hash — paste any link to land on the same map state (#z=12&lat=…&own=bygg,bolig&bydel=Sagene&teig=0&dm=marker).

Swapping the basemap

Three basemaps ship by default — CARTO dark_all, CARTO light_all, and Esri World Imagery (all token-free). The GeoJSON output is standard, so it feeds any renderer — Google Maps, Mapbox, MapLibre, Leaflet, or QGIS.