How We Measure the Bangkok Office Market — Methodology

This page explains how we produce the numbers on our office-market pages (rent, vacancy, occupancy, supply), which buildings we count, and what each term means — so readers and AI can verify and trust the figures. Data covers the 368 buildings OfficeBangkok tracks (not a census of every Bangkok building), as of Sep 2026.

Key terms at a glance

NLA (net leasable area)

The floor area a building can actually lease (excludes common areas/lifts) — the denominator for occupancy.

Occupancy

Share of space already leased = 1 − vacant ÷ NLA. An estimate from verified vacant space, not an owner-certified figure.

Asking rent

The advertised price, before discounts or rent-free periods. The effective (post-incentive) rent is usually lower.

Weighted average

An average weighted by space size — larger spaces count more, reflecting market value better than a plain average.

Which buildings we count (and don't)

We count only leasable Bangkok office buildings that OfficeBangkok actively tracks (currently 368). Occupancy/area calculations use only buildings with complete NLA data (301). We exclude: whole buildings for sale, owner-occupied space not offered for lease, serviced/coworking (covered on separate pages), and buildings we have no data for. So this is a verifiable sample, not a full-city census.

The Grade-A proxy

We group "Grade A" using only attributes we can measure from data: ceiling ≥ 2.9m and/or built 2016 or later (rent-comparison pages also require an asking rent ≥ ฿800). This is a proxy, not a formal grading — real grading also weighs location, lifts, parking, HVAC, management, floor plate and common-area quality. We always label it a "proxy", and admins can override the grade per building for good-but-cheap or expensive-but-tired cases.

What the rule gives on today’s data

Buildings tracked

368

active listings

Pass the proxy

16% of the total

Rule

≥2.9m / 2016

and rent ≥ ฿800

Manually overridden

admin set the grade

A building needs a ceiling of at least 2.9m OR a completion year of 2016 or later, AND an asking rent of at least ฿800/sqm/month. Both halves must hold — a new building asking below that rent does not pass, and neither does an expensive older one with low ceilings.

How we calculate occupancy

Occupancy = 1 − (verified vacant space ÷ NLA)

Clamped to 0–100%. "Vacant space" comes straight from each building's current listing (the same data shown on its page). It is an estimate, not an owner-certified leased rate. Buildings without NLA data are excluded.

Three lenses: whole-market vs like-for-like vs added supply

Whole-market

All buildings surveyed each year — the real whole-market picture, but coverage grows over time.

Like-for-like

Only the same 175 buildings with data EVERY year — apples-to-apples, unaffected by new buildings.

Added supply

Only buildings completed after the base year — shows how fast new supply leases up.

We plot all three together on the vacancy page to show whether falling occupancy comes from new supply leasing up slowly, or existing buildings losing tenants. Like-for-like is a comparison line, not a stand-in for the whole market.

Rent, de-duplication and data freshness

Reported rents are asking rents in ฿/sqm/month. The effective (post-incentive) rent is usually lower.
Weighted avg = Σ(rent × size) ÷ total area · median = the mid-point building (less swayed by a few pricey towers) — we show both.
Each vacant space is counted once per survey — no double counting · each import re-surveys a building fully (not incremental).
"Current" figures are live from each building's latest listing, refreshed on a rolling basis (through Sep 2026) · the 10-year trend uses each December's survey.

Limitations to keep in mind

Not a census — covers tracked buildings; areas with few buildings should be read with caution.
Occupancy is estimated from listed vacancy and can lag very recent moves.
Completion is known by year only (no month) — so lease-up analysis is at year resolution, not monthly.

📊 Market overview → 💰 Office rent → 📉 Vacancy & occupancy → 🏢 Supply →

Verified Sep 2026 · Questions about the data? 081-682-4898