Temporary works design brief approval: a practical handover

A temporary works design can be technically competent and still answer the wrong question if the brief omits a load, sequence, ground condition or interface. The design brief is the handover between the people planning the work and the person designing the temporary solution. Approval of that brief should mean its scope, assumptions and inputs are understood; it should not be treated as technical approval of a design that has not yet been produced.

This page concerns the design-brief gate, before design and site erection. The HSE's temporary works guidance explains that temporary works need planning and management, and that a temporary works coordinator is an effective way to ensure suitable designs are prepared, checked and erected correctly. HSE also says organisations may choose how to arrange management; a particular job title is not a universal legal requirement.

Identify the work and its interfaces

State what the temporary works must do, where they will be used, the intended life, the construction sequence and the permanent works or plant they interact with. Include known site constraints: access, services, adjacent structures, ground information, restricted loads and the activities of other trades. A brief for excavation support is different from one for a working platform; the inputs and people to consult should reflect the actual work.

Name the origin of each critical input. An assumed load or ground parameter that nobody owns is a future dispute. Where information is unavailable, record the uncertainty and who will resolve it. Avoid converting “to be confirmed” into a silent design assumption simply because the project needs to move quickly.

Assign preparation, review and design roles

The person preparing the brief should gather the site and sequence information. A coordinator or other appointed reviewer should check completeness and interface with the construction programme. A competent designer then develops the solution; appropriate design checking may be needed according to complexity. The HSE temporary works FAQ distinguishes design from coordination: appointing a structural engineer to design something does not automatically make that person responsible for the wider temporary works system.

Record who can accept the brief for issue to the designer, who can answer design queries and who can authorise a change to the inputs. Do not invent a signature hierarchy from a generic template. On a simple job one person may perform several roles; that does not remove the need for suitable competence and a clear decision trail.

Review the brief before it becomes an instruction

Ask the reviewer to challenge the purpose, loading, geometry, sequencing, ground or existing-structure information, constraints, interfaces and planned removal. Are there activities that could damage or overload the temporary works after installation? Are the assumptions consistent with available drawings and the site? If a proprietary system is proposed, do manufacturer limits and configuration requirements appear in the brief?

Return a vague brief for correction. Record the query and revised version rather than accepting a verbal clarification that the designer may never see. An accepted brief should be dated, versioned and linked to the source information supplied with it. That record makes later design checks meaningful.

Control change after issue

Changes in plant, load, ground condition or build sequence may invalidate an earlier design input. Provide a route for the site team to raise changes before work proceeds. The coordinator or appointed decision owner should decide whether the designer must reconsider the work and whether a revised brief or design is needed. The updated brief should show what changed and who was told.

The design brief is only the first gate. Design checking, installation, inspection and permission to load or use the works are later, distinct decisions. A RAMS document may describe the method, but it should not be used as a substitute for an engineered design where one is needed.

What to retain

Keep the approved brief version, source drawings and data, review comments, design queries, change records and who accepted each issue. Link these to the subsequent design and site records by temporary works item. If a failure or near miss occurs, the team should be able to reconstruct which inputs and version were in force, rather than finding several files all labelled “final.”

Complys RAMS information may help a buyer explore document organisation for associated work methods. Ask for a demonstration of the current record/version process; do not describe Complys as approving temporary works designs or replacing an engineer, checker or appointed coordinator.

Example: a changed crane platform load

A working-platform brief is issued using the crane and outrigger information available at tender. Before design is complete, the lifting contractor proposes a larger crane. The coordinator should record the new equipment, revised loads and any altered position, then ask the appropriate designer to assess whether the earlier assumptions remain valid. The site should not treat the old brief's acceptance as approval for the new loading. If the designer needs additional ground information, the brief should identify who will obtain it and which work is held meanwhile. Once the design input is agreed, the updated brief and its change reason should reach the designer, checker, lifting team and site supervisor. A drawing labelled “revision B” without the changed input history is harder to audit and easier to misuse.

Where a design brief changes after approval, record the changed assumption and identify which drawings, checks and site instructions it affects. The team should verify that the version used at the workface matches the accepted design information. Keep the earlier version for traceability, while making the current authorised instruction unmistakable.