Building Permits and EIA.

Overview

The Structure Is Not the Same as the Title

When an expat buys a condominium in Thailand, the focus naturally falls on the title deed and the foreign freehold quota. When an expat buys a house, villa or any structure on land, there is an additional layer of legal verification that is often overlooked entirely.

The title deed confirms that the seller has rights over the land. It says nothing about whether the buildings on that land were constructed legally, whether they comply with planning regulations, or whether the relevant authorities have signed off on the finished structure.

Buying a house built without a permit, or built in breach of the permit conditions, means buying a potential enforcement liability. Thai authorities have issued demolition orders against illegally constructed buildings, including properties owned by foreign nationals.

Section 1

The Building Permit (Or Bor 1)

A building permit (issued under the Building Control Act) authorises construction of a specific structure on a specific plot within specific parameters including height, coverage, setbacks and use. The permit is issued by the local authority (the municipality, sub-district administration or, in some areas, a specific regulatory body).

Sellers are not always willing to produce the original building permit. When a permit cannot be produced, this warrants serious caution. Possible explanations range from poor record-keeping to deliberate concealment.

• Request the original building permit before signing any agreement.
• The permit should match the structure actually built in terms of size and use.
• Extensions and additional structures built after the original permit require their own permits.
• A permit issued but subsequently revoked is not a valid permit.
• Permits can be verified with the issuing local authority.

Section 2

The Certificate of Occupation (Or 6)

For condominium developments, the most critical document is the Certificate of Occupation (sometimes called Bor 6 or the occupancy certificate). This confirms that the building has been inspected by the relevant authority and certified as having been completed in accordance with its building permit.

For off-plan buyers, the absence of a Certificate of Occupation is significant. A developer who cannot produce this certificate has not received formal sign-off on the completed building. In some developments, the condominium title deeds cannot be issued until this certificate is obtained.

Section 3

Environmental Impact Assessment (EIA)

Larger developments in Thailand, including condominium projects of a certain size, hotels and resorts, are required to obtain an Environmental Impact Assessment approval before construction begins. The EIA is issued by the Office of Natural Resources and Environmental Policy and Planning (ONEP). On a development purchase above the relevant size thresholds, EIA approval status should be verified before any commitment is made, not after.

Developments built without a required EIA approval face serious legal exposure, including potential demolition. This has been illustrated by enforcement actions in Phuket and Koh Samui involving hotel and resort developments built without proper environmental clearance. An EIA concern is a reason to stop; it is not remediable by negotiating a price reduction.

• EIA approval is required for developments above specified size thresholds.
• Coastal and forested areas have stricter requirements.
• Absence of a required EIA approval is a serious red flag for any development purchase.
• EIA approvals can be verified with ONEP.
• Condominium developers should provide EIA documents as part of standard pre-sale disclosure.

Section 4

Land Use Zoning

Thailand's Town and Country Planning Act divides land into zones with different permitted uses. Residential, commercial, agricultural and conservation zones each have different rules about what can be built and how. Buying land in a zone that prohibits residential use, or buying a commercial structure in a residential-only zone, creates ongoing legal exposure. Current zoning should be checked as part of due diligence — not as a formality, but because zoning issues come up regularly enough to be a substantive question.

Zoning can change. Land near protected areas, coastlines and national park boundaries is particularly subject to regulation and enforcement risk. Zoning should be verified against current planning records, not marketing materials or seller representations.

Section 5

Construction and Permit Checks Before Buying

Buyers often involve a lawyer only after deciding they want a property, by which point they are emotionally committed. The permit check then gets rushed or skipped, because nobody wants to hear bad news at that stage.

Permit and construction checks are a standard part of property due diligence and belong before any commitment. They cover the original building permit verified with the issuing local authority, the Certificate of Occupation, EIA approval status where applicable, current land use zoning, and any outstanding enforcement notices or orders registered against the property.

A problem found at this stage is a problem found before signing. A minor, manageable issue can be addressed; a serious one is a reason not to proceed. That is the value of doing the check before commitment.

• Building permit verification directly with the issuing local authority, not reliance on seller-provided copies.
• Certificate of Occupation confirmed for condominium projects before transfer.
• EIA approval status checked for developments above relevant size thresholds.
• Land use zoning confirmed with current planning records, including coastal and forest setback rules.
• Outstanding enforcement notices and orders checked with local authorities.
• Structural survey by an independent engineer where required.
• A written assessment of any construction risk before commitment.

In Summary

Know before you commit, not after.

Permits, EIA status and zoning should be checked before signing anything on a house or villa purchase.