Temporary Works Coordinator: Role, Responsibilities & CDM Duties

Temporary works failures are among the most catastrophic incidents on construction sites. The collapse of formwork, falsework, scaffolding, or temporary propping can kill multiple people in seconds. The Temporary Works Coordinator (TWC) is the person responsible for ensuring that temporary works are designed, installed, inspected, and removed safely. This guide explains what a TWC does, what competence is required, how the role fits within CDM 2015, and the practical steps for managing temporary works on your site.

What Are Temporary Works?

Temporary works are engineering structures or procedures that are needed during construction but do not form part of the permanent finished project. They include:

• Formwork and falsework -- moulds and supporting structures for in-situ concrete
• Scaffolding -- access scaffolds, loading bays, protection fans
• Temporary propping -- supports for structural elements during alterations or demolition
• Shoring -- supports for adjacent buildings or excavation faces
• Temporary bridges and access roads
• Ground anchors and sheet piling
• Cofferdams
• Tower crane bases and ties
• Temporary drainage and dewatering systems
• Edge protection systems

The key characteristic of temporary works is that they are designed to carry loads during construction that will eventually be transferred to the permanent structure. If they fail, the consequences are typically more severe than the failure of a permanent element because temporary works are often less robust and the people most at risk are directly underneath or adjacent to them.

BS 5975: The Code of Practice for Temporary Works

The standard for managing temporary works in the UK is BS 5975:2019 -- Code of practice for temporary works procedures and the permissible stress design of falsework. This is not a legal requirement in itself, but it represents the accepted industry standard for temporary works management. Failure to follow BS 5975 would be difficult to defend in any enforcement action or litigation following a temporary works failure.

BS 5975 establishes a procedural framework for temporary works that defines three key roles:

1. Temporary Works Coordinator (TWC) -- the person responsible for coordinating all temporary works activities within their area of responsibility
2. Temporary Works Designer (TWD) -- the engineer who designs the temporary works
3. Temporary Works Supervisor -- the person who supervises the installation, use, and removal of temporary works on site

The TWC Role in Detail

The TWC is the linchpin of temporary works management. Their responsibilities include:

Before Construction

• Establishing the temporary works procedures for the project
• Identifying all temporary works items needed and maintaining a temporary works register
• Ensuring temporary works are designed by a competent person
• Checking that temporary works designs are independently reviewed where required
• Coordinating temporary works with the permanent works design

During Construction

• Issuing permits to load for formwork and falsework (formal permission to pour concrete after verifying the falsework is correctly installed)
• Ensuring temporary works are inspected before use and at appropriate intervals
• Managing design changes and variations to temporary works
• Coordinating between different subcontractors whose work affects temporary works
• Ensuring method statements for temporary works are adequate and followed

Removal

• Ensuring temporary works are not removed prematurely (this is one of the most common causes of failure -- removing props before concrete has achieved adequate strength)
• Issuing permits to strike or dismantle
• Verifying that the permanent structure can support the loads before temporary works are removed

TWC Competence Requirements

BS 5975 requires the TWC to be competent, which means having sufficient training, experience, knowledge, and other qualities to perform the role safely. In practice, a TWC should have:

• A construction-related qualification (HNC/HND or degree in civil engineering, structural engineering, or construction management)
• Significant site experience with temporary works (typically 5+ years)
• Specific training in temporary works coordination (the CITB TWC course is widely recognised)
• Understanding of structural engineering principles sufficient to review temporary works designs
• Knowledge of relevant standards (BS 5975, BS EN 12811 for scaffolding, BS EN 12812 for falsework)

On many smaller projects, the site manager acts as TWC. This is acceptable provided they have the necessary competence and are not so overloaded with other duties that they cannot give temporary works the attention required. On larger projects, the TWC is typically a dedicated role.

TWC and CDM 2015

Under CDM 2015, temporary works management falls under several duty holder responsibilities:

• The Designer (Regulation 9) must consider the risks from temporary works when designing the permanent structure. This includes specifying construction sequences that minimise temporary works risks and providing information about design assumptions that affect temporary works (e.g., loading on slabs during construction).
• The Principal Designer (Regulation 11) must coordinate design work, including ensuring that temporary works designs are compatible with the permanent works design.
• The Principal Contractor (Regulation 13) must plan, manage, and monitor construction work, which includes ensuring adequate temporary works procedures are in place.
• Contractors (Regulation 15) must plan, manage, and monitor their own work, including any temporary works they install.

The TWC role is how the principal contractor typically discharges their CDM duties in relation to temporary works. The appointment should be documented, and the TWC's authority to stop work if temporary works are unsafe should be explicitly stated.

The Temporary Works Register

The TWC must maintain a temporary works register. This is a live document that lists all temporary works items on the project, their current status, design information, inspection records, and planned removal dates. A typical register includes:

• Item reference number
• Description of the temporary works
• Location on site
• Designer and design reference
• Independent check status
• Installation date
• Permit to load status (if applicable)
• Inspection dates and findings
• Planned removal date
• Permit to strike status
• Actual removal date

The register should be reviewed regularly (at least weekly on active sites) and updated as temporary works are installed and removed. Digital tools that allow real-time updating are preferable to paper registers. FORGE Command can be used to maintain a digital register as part of the overall project documentation system.

Common Temporary Works Failures

Analysis of temporary works incidents reveals recurring failure patterns:

• Premature removal of props -- striking formwork before concrete has achieved design strength. Always verify concrete strength (cube test results) before issuing a permit to strike.
• Inadequate foundation for falsework -- falsework standards bearing on soft ground, on inadequate sole plates, or on surfaces that cannot support the design loads.
• Overloading -- placing loads on temporary structures that exceed the design capacity. This includes stacking materials on scaffolds or using formwork decks for material storage.
• Missing or loose connections -- scaffold fittings not tightened, falsework bracing not installed, or ties missing from tower crane bases.
• Design not followed on site -- the temporary works are installed differently from the design without the designer's approval. Even small changes (different prop spacing, missing bracing members) can compromise the structure.
• Lack of inspection -- temporary works not inspected after installation, after adverse weather, or after periods of non-use.

Practical Tips for TWCs

1. Walk the site daily -- temporary works conditions change constantly. A daily visual inspection catches problems early.
2. Maintain a clear paper trail -- every design review, inspection, permit, and decision should be documented. In the event of an incident, your records will be scrutinised.
3. Do not sign permits you are not comfortable with -- the TWC's authority to refuse a permit to load or strike is their most important power. Use it.
4. Communicate with subcontractors -- ensure all subcontractors understand the temporary works procedures and their obligations. Include temporary works in site inductions and toolbox talks.
5. Plan ahead -- temporary works are most at risk during transitions (changing from one phase to another, removing temporary works and installing permanent elements). Plan these transitions carefully.