Temporary works register to BS 5975: the register, the TWC and the permits that get skipped

Ask a site for its temporary works register and you will usually be handed a list of falsework and trench boxes. Ask for the permit to load for the hoarding on the road frontage, or the permit to strike for the back-propping under the second-floor slab, and the answer is a pause. The register is only a control if everything that is temporary and carries load or protects people is on it, and if the permits that BS 5975-1:2024 describes are issued for each item. This post is about the items that routinely never make the register and the permits that get skipped as a result.

Where the duty sits

The legal duty is in CDM 2015. Regulation 19 requires all practicable steps to be taken to prevent danger from any structure in an unstable or temporary state of weakness, and requires any buttress, temporary support or temporary structure to be designed, installed and maintained so that it withstands any foreseeable loads and is used only for the purpose it was designed for. Regulation 22 covers excavations: supports or battering to prevent collapse, and inspection by a competent person at the start of every shift and after any event likely to affect strength or stability. The coordinator, the register and the permits come from BS 5975-1:2024, Temporary works. Management procedures for the control of temporary works. Code of practice, which with BS 5975-2:2024 on falsework replaced the single-part BS 5975:2019 in December 2024. Part 1 is the procedural code HSE points to and the one an auditor or inspector measures the site against.

The appointments that make the register mean something

BS 5975-1:2024 describes three roles. The designated individual is the person at organisation level who owns the temporary works procedure and appoints the coordinators. The temporary works coordinator is appointed in writing for the project, with the authority to stop work, and is responsible for the register, the design briefs, the checks and the permits. The temporary works supervisor is the person on site who supervises an item day to day and reports to the coordinator. The appointment letters are the first thing we look for, because a register kept by someone who was never appointed and has no authority to refuse a permit is a list, not a control. The letters name the project, the scope and the authority to stop work, and are signed and dated before the first item goes up.

Design check categories, and who assigns them

Every item on the register carries a design check category, from category 0 for a standard solution that needs no bespoke design, through the categories that require the design to be checked by someone independent of the designer, to the highest category where the check is by a separate organisation. The category is assigned by the coordinator from an assessment of complexity and consequence of failure, and the assessment is recorded. The commonest failure we find is not the wrong category; it is every item at category 1 because that is what the template said, with nothing on file to show that anyone thought about it. A scaffold within a standard TG20:21 configuration is a category 0 item and still belongs on the register, because it still needs inspection at intervals not exceeding seven days under regulation 12 of the Work at Height Regulations 2005. A scaffold outside TG20:21 needs a design, a check at the category assigned, and a check certificate before it is loaded.

Permit to load, permit to strike

The permit to load is the coordinator's written confirmation that an item has been erected in accordance with the checked design, inspected, and may now carry the load it was designed for. The permit to strike is the written confirmation that the load has been taken by the permanent works, or that the condition for removal in the design has been met, and the item may be taken down. Both are numbered, dated, signed and cross-referenced on the register. On the sites we audit, falsework nearly always has a permit to load. Far fewer items have a permit to strike, because striking feels like the end of the risk when it is often the start of it: the slab that is loaded early, the back-propping removed before the pour above has gained strength, the excavation support pulled with people still working at the toe.

The items that never make the register

These are the items we find missing most often, and each one is temporary works under BS 5975-1:2024 as much as a falsework tower is.

• Edge protection. Proprietary barriers, timber guardrails fixed to the structure, and the temporary balustrade on a stair or a slab edge. Each is a structure that has to resist a load, is installed by a trade that did not design it, and is routinely modified when a delivery needs to come through. It needs an item reference, a design or a standard solution, a supervisor, an inspection interval and a note of every alteration.
• Hoardings and fencing. The timber hoarding on the public frontage is a wind-loaded structure that the public walks past. It is designed for the site's wind conditions, it has a check, and it has an inspection interval that shortens when the weather turns. It is also the item most likely to be extended or cut for a gate after the design was done.
• Excavation support. Trench boxes, sheet piles, hydraulic frames and battered faces. Regulation 22 requires the start-of-shift inspection; BS 5975-1:2024 requires the design, the category and the permits. A trench box used outside its manufacturer's rated depth, or with a service crossing that was not in the brief, is a design change, and the register should show it.
• Propping and needling. Back-propping under freshly poured slabs, props to a retained facade, needles through a wall being opened up. Back-propping is assumed by the falsework design above it and is the item the register is most likely to have missed altogether, because it was installed by the same gang as the falsework and nobody raised a separate brief for it.
• Crane bases, piling platforms and temporary roads. The working platform certificate is a design record and belongs on the register with the rest.
• The temporary condition of the permanent works. A steel frame before its bracing is complete, a masonry wall before the floor that restrains it is built, a precast unit before its grout has cured.

What the register needs to show

A register that works has three groups of columns. Identity: the item reference, a description with location and gridline, the category and the assessment behind it, and the supervisor. Design and check: the brief reference and date, the designer and design revision, the checker, the check category and the certificate reference. On site: a status on a ladder that runs from identified through brief issued, design received, check complete, erected, inspected, permit to load, in use, permit to strike, struck and closed; the inspection interval with the last and next-due dates; the permit numbers; and an action flag that turns red when anything is overdue. Our temporary works register guide goes through the columns one by one. Sorted on the flag each morning, it shows which design is out of date, which inspection is late and which item has gone without a permit to strike.

The audit questions we ask

1. Show us the coordinator's appointment letter, signed and dated before the first temporary works item.
2. Pick any hoarding, edge protection or propping on the site and find it on the register.
3. For that item, show the category assessment, the design or standard solution, the check certificate at the category required, and the last inspection record.
4. Show the permit to load and the permit to strike for the last item struck.
5. Show one design change on site and the revised design, re-check and updated register entry that followed it.

A site that can answer all five from the register in ten minutes has a control. A site that answers from a supervisor's memory does not. The Temporary Works Control Pack is the document set we use for the audit above: the procedure to BS 5975-1:2024, the appointment letters, the category assessment tool, the register with the status ladder and the due-date formulas, and the permits to load and strike with worked examples.