Renovation or construction involves more than just structure and architecture. "System works," which include electrical systems, plumbing and sanitary systems, and air conditioning and ventilation systems, are also critically important for the functionality, safety, and hygiene of a building. The laws and standards related to these systems are in place to ensure that buildings can be used efficiently, safely, and do not cause adverse effects on the environment or occupants.

12.1 The Importance of Standard-Compliant System Works

Designing and installing building systems according to prescribed laws and standards is extremely important for:

• Safety: Preventing dangers from short circuits, fires, water leaks, or gas leaks.
• Good Hygiene: Proper plumbing and sanitary systems help prevent the spread of germs and unpleasant odors.
• Functional Efficiency: Standard-compliant systems help make the building comfortable to use and energy-efficient.
• Reducing Maintenance Problems: Correct installation from the start helps reduce minor issues and long-term repair costs.
• Legal Compliance: To ensure construction complies with legal requirements and can obtain the Building Completion Certificate (Form Or.6).

12.2 Laws and Standards for Main Building Systems

Each type of building system has specific laws and standards that must be followed:

12.2.1 Electrical Systems

• Ministerial Regulation Prescribing the Types and Safety Systems for Buildings Used as Commercial or Office Establishments (B.E. 2562): Requires the installation of safe electrical systems, including overcurrent protection devices, appropriate wiring, and grounding.
• Standard for Electrical Installations in Thailand (by EIT – The Engineering Institute of Thailand under H.M. The King's Patronage): Although not a direct law, it is the standard that the Electricity Generating Authority and government agencies use as a guideline for inspection and review.
  
  • Electrical Wires: Must be of a size appropriate for the load, well-insulated, and run in suitable conduits or cable trays.
  • Protective Devices: Must have a Residual Current Device (RCD) and Circuit Breakers of an appropriate size for the circuit.
  • Grounding System: A correct and effective grounding system must be installed to prevent electric shock hazards.
  • Device Installation: The installation of switches, outlets, and other electrical devices must be in safe and appropriate locations for use.

12.2.2 Plumbing and Sanitary Systems

• Ministerial Regulations and Local Ordinances under the Building Control Act: Set standards for:
  
  • Plumbing System: Pipe installation, pipe materials, appropriate water pressure, and prevention of contamination.
  • Sanitary System (Wastewater and Sewage Drainage):
    
    • Number of Toilets/Fixtures: Specifies the minimum number of toilets and sanitary fixtures based on the type, size, and occupancy of the building.
    • Wastewater Treatment Tank (Septic Tank/Aerobic-Anaerobic Tank): Buildings not connected to a municipal combined wastewater treatment system must have a standard primary treatment system.
    • Wastewater Discharge: Treated wastewater must be discharged into the public drainage system correctly, without causing foul odors or flooding.
    • Ventilation for Bathrooms: Every bathroom must have adequate ventilation, which can be an opening to the outside or an exhaust fan.
• Standard for Building Sanitation (by EIT): A professional standard used as a guideline for design and installation.

12.2.3 Air Conditioning and Ventilation Systems

• Building Control Ministerial Regulations (e.g., for high-rise, super-large, and assembly buildings): Require appropriate ventilation and air conditioning systems to control temperature, humidity, and indoor air quality.
• Standard for Ventilation and Air Conditioning (by EIT): Specifies the minimum ventilation rates for different types of rooms, the installation of ventilation systems in bathrooms and kitchens, and the control of indoor air pollution.
• Ventilation for General Buildings: All types of buildings must have adequate ventilation for the good health of the occupants.

12.3 Standards for Built-in Works to Adhere To

Although "built-in works" are not directly system works, their design and installation should consider interaction with building systems and safety standards:

• Access to Systems: Designs should allow for easy access to system components (e.g., circuit breakers, water valves, drain pipes) for maintenance.
• Appropriate Materials: Choose built-in materials that are resistant to moisture, heat, or chemicals (especially in kitchens or bathrooms).
• Electrical Safety: The installation of plugs, switches, or lighting in built-in furniture must comply with electrical standards and have a safe distance from water or heat.
• Ventilation: The design of kitchen cabinets must consider ventilation for the cooker hood, and bathrooms must have an exhaust fan.

12.4 The Role of Engineers and Officials

• Engineers (Electrical, Mechanical, Sanitary): Are responsible for designing, calculating, and supervising the installation of various systems to comply with laws and standards. They must sign to certify the system plans.
• Local Officials: Have the authority to inspect and approve the system plans and to inspect the actual installation to ensure it meets requirements before issuing the Building Completion Certificate (Form Or.6).

12.5 Conclusion

System works are the lifeblood and nervous system of a building. Designing and installing electrical, plumbing, sanitary, and air conditioning and ventilation systems correctly according to prescribed laws and standards not only increases the efficiency and comfort of use but is also a crucial investment in the safety, hygiene, and sustainability of your building. Consulting with system work experts is something that should not be overlooked in any type of renovation or construction. Ensure all systems in your home—electrical, plumbing, and ventilation—work smoothly, legally, and safely with good planning from the start.

References

• Building Control Act, B.E. 2522 (พระราชบัญญัติควบคุมอาคาร พ.ศ. 2522)
• Ministerial Regulation Prescribing the Types and Safety Systems for Buildings Used as Commercial or Office Establishments, B.E. 2562 (กฎกระทรวงกำหนดประเภทและระบบความปลอดภัยของอาคารที่ใช้เป็นสถานประกอบกิจการค้า หรือสำนักงาน พ.ศ. 2562)
• Standards from The Engineering Institute of Thailand (EIT) (มาตรฐานของวิศวกรรมสถานแห่งประเทศไทย - วสท.), including:
  
  • Standard for Electrical Installations in Thailand
  • Standard for Building Sanitation
  • Standard for Ventilation and Air Conditioning
• Relevant Ministerial Regulations and Local Ordinances.