HSG168 and the Joint Code of Practice, UK wide
Construction Site Fire Safety
A building under construction has lost the fire protection of whatever stood there before and has not yet gained its own. Compartmentation is unfinished, escape routes change weekly, the permanent alarm is not live and the fire load peaks exactly when the controls are weakest. AL23 Safety reviews and sets up site fire safety regimes against HSG168 and the Joint Code of Practice for contractors, developers and clients UK wide.
What is construction site fire safety?
Managing fire in a building that does not have a working fire strategy yet
Construction site fire safety is the control of ignition sources, combustible materials, escape provision and emergency response on a site where the permanent fire protection is incomplete. The finished building will have compartment walls, protected stairs, detection and suppression. During the build almost none of that is in place.
Two documents set the benchmark. HSG168 "Fire safety in construction" is HSE guidance, third edition published in July 2022, organised around three themes: eliminate fire risk in design, prevent fire starting and protect people if fire occurs. The Joint Code of Practice is the insurer-backed code that most substantial projects are contractually obliged to follow. Neither is law. Both are what an inspector, a loss adjuster or a court will measure you against.
Who needs one
Anyone running a site and anyone whose cover depends on how it is run
- Principal contractors on projects with an original contract value of £2.5 million or above, which is the Joint Code application threshold.
- Contractors on smaller packages forming part of a larger project valued at £20 million or above, where the Code applies in the same way.
- Developers and clients whose contract works insurance or whose JCT or NEC insurance obligations reference the Code by name.
- Refurbishment contractors, where the Code makes hot work permits mandatory throughout the work.
- Timber frame projects of four or more storeys or with an aggregate floor area of 2,500 square metres or more.
- Any site where the HSE has raised a concern or an insurer survey has come back with conditions attached to cover.
The regulations that apply
Your legal framework, in plain terms
The Regulatory Reform (Fire Safety) Order 2005 applies to construction sites. They are workplaces and article 6 does not disapply them. The Construction (Design and Management) Regulations 2015 run alongside it and put the first duty on designers rather than on the site team. Where the work is to a higher-risk building, the Building Regulations Part 2A dutyholder duties apply as well. Three duty holder maps overlap on the same project. They are cumulative, not alternatives, which is the point most site teams miss when they assume CDM compliance has already dealt with fire.
Article 25 of the Fire Safety Order
The HSE, not the fire and rescue authority, is the enforcing authority for any workplace which is or is on, a construction site. Article 25(2) defines construction site by reference to regulation 2(1) of CDM 2015 and excludes sites to which regulation 36 of CDM 2015 applies, where the fire and rescue authority enforces instead.
Articles 8 and 9 of the Fire Safety Order
General fire precautions must be taken and a suitable and sufficient fire risk assessment carried out. Since 1 October 2023 that assessment must be recorded in full, whatever the size of the operation.
Article 17 of the Fire Safety Order
Everything provided under the Order must be subject to a suitable system of maintenance and kept in an efficient state and in efficient working order. On a site that means the temporary alarm, the extinguishers, the escape signage and the dry riser.
CDM 2015 regulation 9
Designers must eliminate, reduce or control foreseeable risks. The third edition of HSG168 was rewritten around this duty, which is why fire is a pre-construction question before it is a site question.
CDM 2015 also carries duties on emergency routes and exits, on emergency procedures and on fire detection and fire fighting
We cite those regulation numbers from the current consolidated text in your report rather than from memory because reprints and amendments move them.
The Joint Code is not law. That is exactly how it works.
The full title is the Joint Code of Practice on the Protection from Fire of Construction Sites and Buildings Undergoing Renovation. It is published by the Fire Protection Association, produced by RISCAuthority with the Association of British Insurers, the National Fire Chiefs Council, the London Fire Brigade, the Contractors Legal Group and Construction Industry Publications. The current edition is the tenth, published in 2022, incorporating Amendment 1 of January 2023 and Amendment 2 of May 2025. The consolidated document, usually cited as v10.2, was released as a free download on 11 July 2025.
Its force is contractual. Section 2 records that non-compliance can result in insurance ceasing to be available or being withdrawn, which then puts the contractor in breach of a construction contract requiring that cover to be maintained. Amendment 2 rewrote Section 13 on temporary buildings, covering units sited above sites or highways, allowing LPCB LPS 1195 full scale testing as an alternative to individual element testing and revising fire resistance for the supporting members of stacked units. Section numbering moves between amendments so we work from the version your insurer has specified rather than quoting clause numbers at you from a different print.
What the review covers
From the site fire plan to the last permit
- The site fire safety plan itself, covering organisation, escape routes, emergency procedures, materials storage, the hot work regime and security.
- Fire marshal provision, including permanent basing on high fire risk sites and enough deputies to cover holidays, sickness and shift patterns.
- The hot work permit regime, checking that permits name specific identified activities and locations and are signed off daily rather than issued as a blanket over weeks.
- Fire watch discipline, which the Code sets as continuous cover during the work and for at least one hour after it finishes, with further checks at intervals not exceeding 20 minutes for at least one further hour.
- Extinguisher provision at the work position, which the Code puts at a minimum of two, of a type and size matched to the identified risk.
- Temporary fire detection and alarm, including whether temporary buildings within 10 metres of construction structures have detection to BS 5839-1 and whether high fire risk sites are linked to the building alarm and to an alarm receiving centre in the absence of 24 hour security.
- Means of escape, checking that two means of escape are available from the structure at all times and that travel distances are actively minimised as the build progresses.
- Storage and segregation of combustibles, flammable liquids, LPG and waste, plus the housekeeping routine that keeps them where they were put.
- Site security and arson control, covering boundary treatment, out of hours access, lighting and the position of skips and waste against the structure.
- Temporary electrical distribution, task lighting, heaters and drying equipment.
- Interim life safety measures during hot spots in the programme, such as stair enclosure work or the period between removing an existing system and commissioning the new one.
- The interface with any occupied part of the building.
Hot works
Hot works cause a disproportionate share of serious construction losses because the ignition source is deliberate, mobile and applied close to hidden voids. The Code makes permits mandatory once fitting out commences and during all refurbishment work. Our view is that the permit should start earlier than that. We build hot works into your wider permit to work system so that welding, grinding, soldering, bitumen work and hot air stripping run through the same authorisation, isolation and sign off route as confined space entry and live electrical work.
Timber frame
During erection a timber frame is a large area of exposed combustible material with no compartmentation, no fire stopping and no plasterboard encapsulation. It is highly exposed to arson and to hot work. The Joint Code applies its timber frame provisions at four or more storeys or an aggregate floor area of 2,500 square metres or more and requires the extended fire watch regime for large timber structures.
Insurers routinely ask for more: separation distances to boundaries and to other structures, phased construction, early plasterboard encapsulation, off-site prefabrication, hardened security and a total no smoking regime. Treat those as market practice rather than published requirements unless your insurer has set them out in writing. We get that in writing before the job is priced, not after the frame is up.
Phased occupation
Two fire regimes running inside one building at the same time
Partial handover is where site fire safety usually fails. The occupied part needs a completed fire strategy, working detection, protected escape routes and a responsible person with a recorded fire risk assessment. The rest is still a construction site with incomplete compartmentation and an HSE enforcement route under article 25.
The questions are the same on every project. Where is the physical separation between the occupied part and the works and what fire resistance does it actually achieve? Do the occupied escape routes pass through, under or alongside the works? Is the alarm one system or two and who hears what? Who is the responsible person for each part and how do they co-operate as the Order requires? Where the building is a higher-risk building, occupation cannot begin at all until the Gateway 3 completion certificate has been issued and the building is registered.
Our process
From design review to milestone verification
- 01
Pre-construction review
We look at the design, the construction phase plan and the programme and identify where the fire risk was designed in rather than managed out.
- 02
Site inspection
We walk the site against HSG168 and the Code, including hot work in progress, escape routes as they stand that day, temporary detection and storage.
- 03
Report
A graded findings report, each item tied to the specific provision it comes from, separating legal duty from insurer condition from good practice.
- 04
Fire plan and permits
We write or rewrite the site fire safety plan, the hot work permit and the emergency procedure and brief the marshals.
- 05
Verification
We return at agreed programme milestones, especially at first fit, at handover of any occupied phase and before the temporary system is removed.
What you get
A plan for this site, not a template
- A site fire safety plan specific to this site, not a template with your logo on it.
- A findings report separating legal duty, insurer condition and recommended practice, with owners and dates against each item.
- A hot work permit form and procedure, including the fire watch requirement and the daily sign off.
- A temporary fire detection and alarm specification, with the BS 5839-1 provision and any alarm receiving centre link set out.
- An escape route and muster plan that is updated at each programme stage rather than drawn once.
- A short brief for your insurer or loss adjuster confirming what has been checked and what remains open.
What we need from you
The plan, the cover and a walk round
- The construction phase plan, the programme and the current site layout drawings.
- Your insurance conditions and any survey report or warranty attached to the cover.
- The existing hot work permit and fire plan however incomplete.
- Site access, an induction slot and a walk with whoever runs the site day to day.
- Details of any occupied or handed over part of the building.
Why AL23 Safety
Law and insurer condition kept apart
Accountable
Where a permit regime is a paper exercise or a stair is not a usable escape route, we say so on the day, in front of the people who can change it.
Expert and chartered
Qualified, chartered professionals, with fire engineering and construction safety in the same team rather than in two supply chains.
Practical, not just compliant
We separate what the law requires from what your insurer requires so you can argue the second one on its merits instead of paying for it by default.
UK wide
We support sites across the UK, alongside broader construction health and safety and CDM advice.
Get a view before the insurer sends a surveyor
Tell us the project value and the stage and we will tell you what is involved
Contract value, build type and programme stage are enough to scope a visit. If your regime is already sound and you only need it documented properly, we will say that.
Common questions
Answers, up front
Cannot see your question? Get in touch and we will answer it directly.
Contact usIt applies to projects with an original contract value of £2.5 million or above and to smaller contracts forming part of a larger project valued at £20 million or above. Below those thresholds it is not engaged by the Code itself. Your insurer can still make it a policy condition on a smaller job so read the cover rather than the threshold.
Normally the HSE. Article 25 of the Fire Safety Order makes the HSE the enforcing authority for a workplace which is or is on, a construction site, with an exception where regulation 36 of CDM 2015 applies. Fire and rescue authorities still attend incidents and still enforce in the occupied parts of a partly handed over building.
Yes. Article 9 applies and since 1 October 2023 the assessment must be recorded in full. It has to be a live document on a site, reviewed as the structure, the escape routes and the fire load change, rather than a single assessment written at mobilisation.
The Code makes permits mandatory once fitting out commences and during all refurbishment. Before that point the permit is not mandatory under the Code but the risk is still there and a fire that starts during frame erection is not a smaller fire. We recommend a permit from day one and we have never seen an insurer object to it.
It depends on the size and stage of the site, the number of visits across the programme, whether we are writing the fire plan and permit system from scratch and whether an occupied phase is involved. A one off review of a single site is a very different job from a fire regime running across a two year programme. Send the project value and the programme and we will price both.
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