ShophouseMetropolis

Documented cluster · Samphanthawong

Wanit 1–Sampheng fabric

ตึกแถววานิช 1–สำเพ็ง

The dimensions actually measured

Footprints screened
260morphology only, never surveyed
Median frontage
5.9 mcitywide 5.1 m
Median depth
12.4 mcitywide 13.6 m
Deepest tenth
27.1 mp90 · citywide 27.6 m

Frontage and depth are the short and long sides of each footprint's minimum-area bounding rectangle, computed by scripts/build-shophouse-spine.py over the Overture/OSM screen. A footprint in this set has not been visited: the shape says shophouse, and nothing here says it is one.

What binds these buildings

Computed per footprint from depth, plot and neighbours — not merely listed. A clause counts as binding when this building's own geometry triggers it.

  • MR55 ข้อ 41153 of 260

    Setback from public road centreline: 3 m; 6 m where the road is under 10 m wide, for buildings over 2 storeys or 8 m — including ตึกแถว.

    THE decisive clause. An old shophouse occupies its whole plot because it predates this. Demolish it and the replacement must step back onto ground that, on a 12 m plot, is most of the site — so on many plots you cannot lawfully rebuild what you tear down.

  • MR55 ข้อ 276 of 260

    Each คูหา: width ≥ 4 m (column centreline to centreline); depth ≥ 4 m and ≤ 24 m; ground-floor area ≥ 30 m². If depth exceeds 16 m, an uncovered void of ≥ 10% of ground-floor area between 12 and 16 m depth.

    The 4 m module is a floor set by law. Tirapas's surveyed 4 m module is the regulation made visible.

  • MR55 ข้อ 436 of 260

    Continuous construction ≤ 10 คูหา and total row length ≤ 40 m, regardless of ownership.

    Why long shophouse streets break into readable blocks with gaps. The rhythm you see from the pavement is a fire rule.

Already over the depth cap
35deeper than the 24 m ข้อ 2 allows a new build
Median row length
2 unitsข้อ 4 caps a continuous row at 10
Rows over that cap
16lawful when built, unbuildable now

The interesting number is the third. Where a row exceeds today's cap, the building standing there could not be built again — which means demolition is not a reversible decision, whatever replaces it.

Where the pressure sits

Each footprint is placed on two axes: the appraised land value underneath it, split at the citywide median of ฿3,568,750, and its plot depth, split at 13.6 m — below which a 2 m setback takes a serious share of any compliant replacement.

  • Worth reconsidering41

    High land value, shallow plot.

    Maximum pressure to demolish — and the plot is shallow enough that a compliant replacement loses a serious share of its footprint to the setback. Demolition here is closest to self-defeating, and it is the owner who is least likely to have been told.

  • Genuinely exposed95

    High land value, deeper plot.

    The land is worth enough to justify clearing and the plot is deep enough to absorb a setback. On present rules these are the ones that go, and an argument for keeping them has to be made on carbon, tenure or social capital rather than on the code.

  • Reuse is the easy answer94

    Lower land value, shallow plot.

    Little pressure to clear, and the setback would bite hard if anyone tried. Nothing needs defending here yet — which makes it the cheapest place to test what adaptive reuse actually costs.

  • Not under pressure5

    Lower land value, deeper plot.

    Neither the market nor the code is currently forcing a decision. Worth surveying precisely because there is time to do it properly.

25 of the 260 footprints here carry no quadrant, so the split above sums to 235 rather than 260. That is a join artefact, not a gap in the screen: the pressure layer classifies all 2,433 footprints, but the spine joins the two sets by centroid rounded to five decimal places, and 241 of the 2,433 miss that key by a metre or so. Those buildings have a quadrant; this page cannot currently name it.

Land under one footprint
฿4,587,500median · citywide split ฿3,568,750
District appraisal band
฿62,500฿250,000per m², Treasury appraisal

Appraised value is the base for transfer tax and sits below market, so every figure here is a floor, not an estimate.

What this page cannot tell you

Storeys are known for 4 of the 260 footprints here 256 carry none, and are left null rather than filled with a plausible number. Across the whole spine the same is true of storeys (for two-thirds of the set), tenure, structural condition, road width, build year.

  • Morphology is not proof. A narrow, deep footprint repeating along a street is the shophouse signature, but no field survey has confirmed that any individual building here is one, nor its age, condition or tenure.
  • Appraised value is the base for transfer tax and sits below market, so every land figure is a floor rather than an estimate.
  • The setback exposure assumes a road width, because per-plot road widths are not published — the assumption is stated in SPLITS and can be changed.

Where this comes from

This is density before towers: tiny frontages, deep stock rooms, handcarts and upper-floor households. It works because the block is porous, not because the buildings are individually grand.

Ultra-fine-grain wholesale shophouse rows

Period
19th century onward
Kind
market row
Register id
FAD-5648
District
Samphanthawong

Documentation: Fine Arts Department GIS register. Every computed figure on this page comes from scripts/build-shophouse-spine.py, which states each rule in its header.

Arkara, N. (2026). Wanit 1–Sampheng fabric — documented shophouse cluster (260 screened footprints) [Data set]. Shophouse Metropolis, BKKx. https://shophouses.nonarkara.org/shophouses/cluster/wanit-sampheng

All 32 clusters · the pressure map · the datasets behind them