Overview
ISO 24359-1:2026 is the International Standard for planning the building commissioning (Cx) process in new building projects. Developed by ISO/TC 205, this standard focuses on the creation of a comprehensive commissioning plan for new construction, major renovations, or system and assembly replacements. The commissioning process starts in the earliest project phases and extends through pre-design, design, construction, building turnover, and the first year of building operation, ensuring that project outcomes align with the owner's requirements. ISO 24359-1:2026 offers a universal process framework designed to work in conjunction with discipline-specific or system-specific standards.
Key Topics
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Commissioning Plan Development
The standard outlines requirements for preparing a project-specific commissioning plan. This includes documenting which systems or assemblies will be commissioned, roles and responsibilities, communication protocols, commissioning activities, procedures, schedules, and methods of documentation.
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Project Phases Covered
- Pre-design and design
- Construction
- Turnover
- First year of operation
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Owner’s Project Requirements (OPR)
The commissioning process is based on clearly identified OPR, including performance goals, targeted outcomes, and quality criteria for all commissioned systems.
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Risk Assessment
ISO 24359-1:2026 guides users through a multi-factor risk assessment to determine the appropriate scope and rigor of commissioning activities based on factors like cost, building usage, complexity, sustainability goals, and prior experience.
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Commissioning Provider Independence
Specifies levels of independence required from the commissioning provider depending on the complexity and risk level of the project.
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Commissioning Deliverables
- Commissioned systems manual
- Commissioning reports (preliminary, progress, and final)
- Issues and resolution logs
- Training plans for operations and maintenance personnel
Applications
ISO 24359-1:2026 is intended for use by:
- Building owners and project managers overseeing new constructions or major renovations
- Commissioning providers (CxPs), who plan, coordinate, and document commissioning activities
- Design, engineering, and construction teams seeking consistent quality and project delivery
- Facility managers and building operators engaging in the first-year building operation
Practical value includes:
- Ensuring that the built environment meets documented owner expectations for quality, performance, and sustainability
- Facilitating clear communication among owners, design teams, contractors, and operators throughout all project phases
- Integrating commissioning requirements clearly into tender documents and contractual processes
- Reducing operational risks through early identification and resolution of issues during design, construction, and turnover
- Supporting long-term operational efficiency through structured training, documentation, and performance verification
Use Cases:
- New office buildings, hospitals, schools, and complex mixed-use developments
- Major systems retrofit in existing facilities (excluding ongoing retro-commissioning or recommissioning, which are not covered)
- Projects utilizing diverse project delivery methods, such as design-build or integrated project delivery
Related Standards
ISO 24359-1:2026 is designed to be applied in concert with other internationally recognized standards covering specific building systems or performance testing, including:
- ISO 16813 – Indoor environment design
- ISO 21105 series – Commissioning of building enclosures
- ISO 19455 series – Functional performance testing of technical systems
- ISO TS 21274 – Commissioning of lighting systems in buildings
Future Extensions:
- ISO 24359-2 (under development): Standard for commissioning in existing buildings, including recommissioning and retro-commissioning
Keywords:
building commissioning, commissioning plan, new construction, project requirements, ISO 24359-1:2026, quality assurance, risk assessment, project delivery, owner’s requirements, building operation, commissioning provider, building systems, construction quality
Implementing ISO 24359-1:2026 helps project teams deliver buildings that consistently meet owner requirements, reduce operational risks, and support industry best practices for commissioning in new construction.