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November 21, 2025

Thailand Eases Rules for Solar Rooftop Installations

On November 17, 2025, Thailand’s Ministry of Interior introduced significant regulatory changes to make rooftop solar adoption easier and more cost-effective for property owners. Ministerial Regulation No. 72 B.E. 2568 (2025), issued under the Building Control Act B.E. 2522 (1979), was published in the Government Gazette on November 19, 2025, with immediate effect.

Background

Under the Building Control Act (BCA), any alteration made to a building requires either notification of the relevant authority or application for a building alteration permit—unless the alteration falls under a separate list of exceptions specified in the ministerial regulations issued under the BCA. In 2015, installation of solar rooftops on any residential building under 160 square meters was added to this list of exceptions, subject to inspection and notification requirements.

The newly enacted regulation now eliminates many of these requirements and introduces a broader and more permissive framework to promote solar adoption nationwide.

Key Changes

Specifically, the regulation introduces three major changes:

  • Expanded exemption from the definition of “building alteration”: The installation of solar panels on any building roof—regardless of the type of building or the total area of the installation—is no longer considered a building alteration under the BCA, provided that the total weight of the installation does not exceed 20 kg/m2.
  • Removal of structural integrity certification requirement: The new regulation eliminates the obligation to obtain a structural stability certificate from a licensed civil engineer.
  • Removal of notification requirement: Property owners or possessors are no longer required to notify the local authority before installation of a solar rooftop.

Impact

This significant streamlining of requirements for solar rooftop installation is expected to accelerate the adoption of renewable energy in the country, particularly for residential and commercial properties—similar to the way Thailand’s December 2024 removal of licensing requirements for factory solar rooftop installations encouraged such adoption in the industrial sector.

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