Comparison of the Construction Budget of Buildings Designed According to the Ministerial Regulation No. 6 B.E. 2527 and Designed According to the Ministerial Regulation B.E. 2566 A case study of the Thai Family House Building 3

Abstract

This research aimed to (1) investigate construction cost rates for building designs under Ministerial Regulation No. 6 B.E. 2527 and Ministerial Regulation B.E. 2566, and (2) analyze the impacts and comparative assessment of construction cost rates resulting from the implementation of Ministerial Regulation B.E. 2566. The study employed the Thai Family Happiness House 3 as a case study, representing a two-story reinforced concrete building. A comparative analysis framework integrating quantitative and qualitative methodologies was applied. The research methodology comprised five principal phases: examination of relevant theories and regulatory requirements, case study building selection, structural design according to both regulatory frameworks using the Working Stress Design (WSD) method, cost estimation through Bill of Quantities preparation, and impact analysis with construction cost rate comparison. The findings revealed that implementing Ministerial Regulation B.E. 2566 resulted in a construction budget increase from 541,844.64 THB to 597,588.03 THB, representing a 10.28% escalation. Reinforced concrete work exhibited the highest increase at 25.89%, followed by earthwork, sand, and foundation work at 51.4%. These increases stemmed from more stringent regulatory requirements, including the extension of pile head cover from 5 cm to 15 cm, implementation of 7.5 cm eccentricity load requirements, and wind load enhancement from 50 kg/m² to 60 kg/m². The study's outcomes align with related research demonstrating the substantial impact of regulatory modifications on construction costs. This research provides critical information for construction industry stakeholders, including designers, cost estimators, and project owners, facilitating budget planning and preparation for compliance with new regulations that emphasize enhanced structural safety and sustainability. The findings contribute to the understanding of regulatory impact assessment in construction economics and provide a framework for future studies examining the cost implications of building code revisions.