Bangkok area condos and apartment buildings - research file (built 2026-10-31)
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13,167 rows in Bangkok, Nonthaburi and Samut Prakan:
- 4,656 registered residential condominiums (one row per registered condo, which can
  hold several buildings), 63% placed on the map
- 8,511 rental apartment buildings and dormitories, all placed

Sources and credits
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- Treasury Department condominium appraisal list (gdpublish-condominium-valuation,
  via gdcatalog.go.th, labelled "Open Data Common"): every condo with unit title deeds.
  Gives names, districts, subdistricts, buildings and floors. This is the master list.
- Department of Lands condominium search (dol.go.th/building, fetched 2026-10-31):
  name, buildings and exact unit count for every registered condo in the three
  provinces (4,078 records), matched by name to 2,164 Treasury condos. The site marks its
  data as preliminary and gives no reuse licence; unit counts are facts.
- National Housing Authority, via gdcatalog.go.th ("Open Data Common"):
  registered condo projects with unit counts (used for 157 public-housing condos),
  the 2021-22 low-rent rental survey (rooms counted; Bangkok and Samut Prakan only;
  only building facts are kept, nothing about the people interviewed), and the
  public and private project map layers (dhds.nha.co.th), used to place condos by name.
- Department of Lands 2024 condo registrations (13 rows, via gdcatalog.go.th) and
  "Condominiums in Bangkok (1981-2017)", Sarasatr 3(1), 2020: used to check the totals.
- OpenStreetMap, (c) OpenStreetMap contributors, ODbL 1.0: boundaries, basemap,
  building names and outlines, apartment buildings. If you share this file or a
  database made from it, keep it under ODbL and credit OpenStreetMap.
- Overture Maps places, release 2026-10-21 (CDLA-Permissive-2.0 / CC0 / Apache-2.0 by
  source): names and locations used for matching, apartment buildings.

Please check the "Open Data Common" terms with the publishing agencies before any
commercial use: the licence is named on the catalogue but its text was not found.

Coverage
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Condos: name 100%, district 100%, floors 100%, on the map 63%, units 100% (47% exact, 53% estimated)
Apartments: name 100%, on the map 100%, units 17% (12% counted, 4% estimated), floors 7%

Known limits
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- Condo units: 2,164 are exact from the Department of Lands register and 34 from the
  National Housing Authority. The rest are ESTIMATES. The estimate is
  floors that hold flats (summed over the condo's buildings, from the Treasury list)
  times typical flats per floor: 10 for walk-ups up to 5 floors, 20 for 6-8 floors,
  18 for taller towers. Exact and estimated together give about 1.08 million units in
  Bangkok, against 711,358
  registered by 2017 and an expected 1.0-1.1 million by 2026. Individual buildings can be
  far off: luxury towers come out too high, micro-unit towers too low. Checked against
  the 1,954 condos that now have an exact count, the estimate was right on average
  (median ratio 0.96) but half were off by more than a third.
- Condos are placed by matching their registered name against named places in
  OpenStreetMap, Overture and the National Housing Authority surveys within the same
  district. Thai names were also machine-transliterated into likely English names to
  match English-only map entries; those transliterations are used only for matching
  and are never shown as names. match_confidence = "low" marks loose or partial matches.
  1,720 condos (37%) found no match: they are in the CSV with their district and
  subdistrict but no coordinates.
- "name_en" is the English name found on the matched map entry, not an official name.
- Apartment buildings come from open map data, so coverage is uneven and depends on what
  people have mapped. Buildings of 20+ floors, serviced apartments and hotels were left
  out, as were map entries sitting on a registered condo's location.
- Treasury floors are the highest floor number listed; Thai buildings often skip floors
  13 or 4, so the true count can be one or two less.
- price_per_m2 is the Treasury appraisal value (baht per m²) of the highest-valued
  residential floor, not a market price.
- Department of Lands matching: a condo is matched only when the province, name and every
  number in the name agree (building letters too). About 1,180 older Department of Lands
  records are listed under the developer company's name rather than the condo's, so they
  cannot be matched by name. Where both registers have a count, the Department of Lands
  and the National Housing Authority agree (median ratio 1.00).