What Triggers a New Fire Risk Assessment After Refurbishment Works?

A fire risk assessment after refurbishment is not a paperwork exercise. It is the point at which the responsible person decides whether the building still works as a fire safety system, or whether the works have quietly broken something that used to function. Under the Regulatory Reform (Fire Safety) Order 2005, the assessment must be kept under review and revised whenever there is reason to suspect it is no longer valid or there has been a significant change to the premises. Building works are one of the most common reasons that test is triggered.

The difficulty for most facilities managers is not the principle. It is judging when a project crosses the line from cosmetic refresh into significant change. Repainting a corridor is not the same as moving a corridor. Replacing a few ceiling tiles is not the same as opening up a compartment line. The legal duty does not list every scenario, which is why a defensible decision needs to be based on what the works actually altered, not what the project was called on the purchase order.

This article sets out the test, the scenarios that almost always require a fresh assessment, the borderline cases that need judgement, and the practical issues that catch teams out once contractors have already left site.

When Building Works Trigger a Fresh Fire Risk Assessment

Article 9(3) of the Fire Safety Order requires the fire risk assessment to be reviewed regularly and revised where it is no longer valid or where there has been a significant change to the matters to which it relates, including the premises, the people present, and the activities carried out. Building works can affect all three.

The trigger is not the cost of the project or its planning status. A two-week, low-value alteration that removes a fire door from a protected stair affects the risk profile more than a six-figure decorative scheme that leaves the building fabric untouched. The right question is whether the works changed anything that the existing assessment relied on. If they did, the assessment is no longer accurate in those areas, and a review or new assessment is needed before the building is reoccupied or the works are signed off.

In practical terms, the trigger usually falls into one of four categories. The works altered the building fabric or compartmentation. The works changed the means of escape. The works introduced new fire load, ignition sources or hazardous processes. Or the works changed who uses the building, how, or when. Any of these can invalidate a previous assessment, and most refurbishments touch more than one.

Understanding the Significant Change Test Under the Fire Safety Order

The Order does not define “significant change” with a checklist. It expects the responsible person to apply judgement to the building, the occupants and the activities. Government guidance accompanying the Order, and the more recent updates flowing from the Fire Safety Act 2021 and the Building Safety Act 2022, all reinforce the same point. Significance is judged by impact on fire safety outcomes, not by the label attached to the project.

A workable test, and one that holds up under scrutiny from enforcing authorities, is to ask whether the works have changed any of the following:

• The layout, configuration or use of the premises
• The compartmentation, fire separation or protected routes
• The means of escape, including travel distances and final exits
• The fire detection, alarm or suppression systems
• The emergency lighting or signage
• The fire load, including stored materials, furniture, fittings or stock
• The number, type or vulnerability of occupants
• The processes carried out, particularly anything involving heat, flammables or hot works
• The access available to the fire and rescue service

If the answer is yes to any of these, the existing assessment is unlikely to still be valid in full. That does not always mean a complete new assessment from scratch. Sometimes a properly documented review and revision is enough. But the documented decision must be defensible, and it must be made by someone competent to make it.

The point that often gets missed is that significance is cumulative. A series of small alterations, none of which would have triggered a review on its own, can add up to a meaningfully different building. A new tea point here, a partition there, a change of tenant on the second floor, a new server cabinet in a riser cupboard. Two years on, the assessment in the file describes a building that no longer exists.

Refurbishment Scenarios That Almost Always Require a New Assessment

Some categories of work are almost guaranteed to invalidate the existing fire risk assessment. If the project involves any of the following, plan for a fresh assessment as part of the programme, not as an afterthought.

Changes to Compartmentation or Fire Separation

Anything that opens up a compartment line affects the building’s ability to contain a fire. New doorways through fire-rated walls, removal of a fire-rated partition, penetrations through floors or ceilings for new services, and any opening up of risers, ducts or voids should all be treated as significant. Even where the contractor intends to reinstate the line with the correct fire stopping, the assessment needs to confirm the work was done properly and that the reinstated compartment performs as designed. Poor fire stopping around new cable trays and pipework is one of the most common defects found on post-works inspections.

Alterations to Means of Escape

Anything that changes how people get out of the building is significant. New partitions that affect travel distances, repositioning of final exits, locked or restricted doors on escape routes, narrowing of corridors, new mezzanines, and changes to stair access all need reassessing. Travel distance calculations from the original assessment may no longer hold, and the occupancy capacity of escape routes may need recalculating where layout or use has changed.

Changes of Use or Occupancy

If part of the building has been converted from office to storage, from retail to food preparation, from general use to a sleeping risk, or from low occupancy to high occupancy, the fire strategy itself may need rethinking. Sleeping accommodation in particular carries a very different risk profile and is treated more strictly under both the Fire Safety Order and the guidance that supports it. A change of use should never be signed off without a fresh assessment reflecting the new occupancy.

Major Mechanical, Electrical or Plant Works

Plant rooms, risers, boiler installations, large electrical upgrades, the addition of solar PV, battery storage or EV charging, and significant HVAC reconfiguration all introduce new ignition sources or fuel loads, or change how a fire would spread. The same applies to commercial kitchen refits, especially where extract ductwork or suppression systems have been altered.

Fire Safety System Changes

If the fire alarm has been extended, reconfigured, downgraded or upgraded, if zones have been changed, if detection has been added or removed, or if emergency lighting and signage have been altered, the assessment that referenced the previous arrangement is no longer accurate. A new commissioning certificate from the contractor is not the same thing as a revised fire risk assessment.

External Wall and Facade Works

For relevant buildings, external wall works carry specific implications under the Fire Safety Act 2021 and post-Grenfell regulatory updates. Recladding, insulation upgrades, new balconies, replacement windows and changes to facade penetrations should all be referred for a fresh assessment that explicitly considers external fire spread. This is not an area for informal review.

Structural Alterations

Removal of walls, formation of openings, mezzanine installation, atrium creation and any change to floor plates can affect both compartmentation and means of escape. These works should be matched by a fresh assessment before reoccupation.

Borderline Works and How to Judge Them Sensibly

Not every project is clear cut. Plenty of refurbishments sit in the middle ground, where the works are more than decorative but stop short of structural. This is where facilities managers earn their keep, and where a documented decision matters more than the decision itself.

Examples of borderline works that need judgement rather than an automatic response:

• Replacing fire doors like-for-like with certified equivalents
• Internal redecoration that involves removing and reinstating ceiling tiles
• Reconfiguring a small number of demountable partitions in an open-plan office
• Adding a single new tea point or kitchenette
• Replacing carpet, floor finishes or wall finishes with materials of similar fire performance
• Installing additional power or data points without affecting compartmentation
• Adding a small number of workstations within existing occupancy capacity
• Replacing a section of suspended ceiling within a single room

In each of these, the works may not change the fire strategy at all, or they may quietly affect compartmentation, smoke containment or escape routes depending on how they were actually carried out. The question is not what the scope of works said, but what the contractor did on site.

The sensible approach for borderline works is a structured review rather than a full new assessment. That review should consider what the existing assessment relied on, what the works changed in practice, whether any fire-rated elements were disturbed and properly reinstated, and whether any new hazards or activities have been introduced. Where the review confirms that nothing material has changed, the existing assessment can be retained with a dated note recording the review and its conclusion. Where the review identifies gaps, those sections should be revised, or a fresh assessment commissioned.

Two practical rules help with borderline calls. First, any time a fire-rated element has been disturbed, treat reinstatement as something that needs to be verified, not assumed. Photographs from the contractor are not the same as a competent inspection of fire stopping above the ceiling line. Second, where there is genuine doubt, commission the fresh assessment. The cost of a properly scoped review is small compared with the cost of an enforcement notice, an insurance dispute, or an injury claim where the fire risk assessment described a building that did not match reality.

What a Fire Risk Assessment After Refurbishment Should Cover

A post-refurbishment assessment is not a generic template exercise. The assessor needs to understand what the works changed and look specifically at those areas, while still confirming that the wider building remains compliant. A useful post-works assessment normally covers the following ground.

The scope of the recent works, drawn from drawings, specifications and a site walk rather than a verbal summary. Without this, the assessment cannot demonstrate that the changes have actually been considered.

Compartmentation, with particular attention to any new or reinstated fire stopping. This usually involves inspection above ceilings, inside risers and around new service penetrations. Where access is not available on the day, the limitation should be recorded and a follow-up arranged rather than left as an open assumption.

Fire doors installed, replaced or relocated during the works, including verification of certification, gaps, seals, hinges, closers and signage. New doors that have been installed without third-party certified evidence are a common finding.

Means of escape, including revised travel distances, exit widths, final exit arrangements, signage and emergency lighting coverage against the new layout.

Fire detection and alarm coverage in any altered area, including category, zoning and integration with the wider system. Where the works have changed room layouts, detector positions may no longer comply with the relevant British Standard.

New fire load and ignition sources introduced by the refurbishment, including furniture, stored materials, kitchen equipment, IT and any plant additions.

Occupancy and use of the altered space, including any changes to the type, number or vulnerability of people present.

Management arrangements, including evacuation plans, drills, fire warden coverage, signage, induction for new tenants or staff, and updates to the building’s fire safety log.

External fire spread considerations where the works touched the facade, roof or any external feature for relevant buildings.

An action plan that is specific and dated, not a list of generic recommendations. Anyone reading the assessment six months later should be able to see what was wrong, what was done, and by when.

Where the works were significant, the output should be a new assessment document rather than an annotated version of the previous one. A fresh document gives a cleaner audit trail for insurers, enforcing authorities and any future sale or letting.

Common Mistakes Facilities Managers Make Post-Works

Most of the problems found on post-refurbishment fire risk assessments come from the same handful of mistakes. They are worth knowing in advance because they are almost all avoidable with better sequencing of the project.

Relying on contractor sign-off as evidence of fire safety compliance. A building control completion certificate, a CDM handover pack or a principal contractor’s sign-off is not a fire risk assessment. They cover different ground and serve different purposes. The responsible person’s duty under the Fire Safety Order sits with them, not the contractor.

Assuming the existing assessment is still valid because no one has officially decided otherwise. The default position under the Order is that an assessment must be revised when there is reason to suspect it is no longer valid. The absence of a decision is not the same as a decision that nothing has changed.

Not inspecting concealed fire stopping. New service penetrations through compartment walls and floors are routinely sealed badly or not at all. Once the ceiling tiles go back up, the defect is invisible until something else triggers an inspection. Specifying a fire stopping inspection as a separate line item in the project, with photographic records and a competent inspector, is one of the most useful steps a facilities manager can take.

Reusing fire doors that have been removed and reinstated during the works. A certified fire door is only certified in its original installed configuration. Removing it, storing it on site, and refitting it later can compromise the seals, the frame fixings and the certification.

Letting tenants move back in before the assessment has been reviewed. Once occupation has resumed, retrofitting a fresh assessment becomes harder, especially where access to ceilings and risers is now obstructed by furniture, IT or stock.

Treating fire safety as a separate workstream from the rest of the project. Where the fire risk assessor is brought in at the end as a tick-box exercise, the defects found are expensive to remedy. Where they are involved at the design and snagging stages, problems are caught while contractors are still on site and the cost sits within the project budget.

Overlooking the management arrangements. A new layout often needs new evacuation plans, revised fire action notices, updated personal emergency evacuation plans for any vulnerable occupants, and re-briefing of fire wardens. A perfectly compliant physical building still fails if no one has updated the procedures.

Not updating the fire safety log book or the building’s golden thread of information where the Building Safety Act applies. The records need to reflect what the building actually is, not what it was before the works.

Timing, Responsibility and Working With Contractors

The responsible person under the Fire Safety Order does not change because a refurbishment is underway. The duty to ensure the assessment remains valid sits with them throughout the project, not just at the end. In practice, this means treating fire safety as a continuous obligation across the works, with three clear points where attention is needed.

Before the works start, the existing assessment should be reviewed against the planned scope. This identifies what the project will affect and what needs to be in place by the end. It also flags any temporary risks that the works themselves will introduce, such as compromised compartmentation, blocked escape routes, hot works permits, increased fire load on site, and reduced alarm or detection coverage during certain phases. A short interim fire risk assessment covering the construction phase is often sensible for anything more than minor works, particularly where the building remains partly occupied.

During the works, fire safety needs to be managed actively. This includes the management of hot works, daily checks on escape routes, protection or isolation of detection where necessary, and clear arrangements with the contractor for who is responsible for what. CDM duties and the Fire Safety Order overlap here, and the boundary should be agreed in writing before the project starts.

After the works, the assessment should be reviewed and revised, or a new one commissioned, before full reoccupation. This is the point where the temptation is greatest to defer, because the project is over budget, the programme has slipped, and tenants want to move back in. Holding the line on a proper post-works assessment is part of the responsible person’s duty, and it is also where most of the avoidable enforcement and insurance exposure sits.

Working with contractors well is the other side of this. The principal contractor and the design team should know from the outset that a fire risk assessment will be commissioned after completion, what it will look at, and what evidence will be expected. This shapes how they specify, install and document the fire-critical elements. Where the contractor knows that fire stopping will be inspected above the ceiling line, the standard of that work tends to be noticeably better than where it will not.

For larger projects, particularly those affecting compartmentation, external walls or fire safety systems, involving a competent fire risk assessor at the design review stage usually pays for itself several times over. It is cheaper to design out a problem than to remediate it after handover.

Useful background on the legal framework is available in the government guidance on the Fire Safety Order, and a working understanding of the Order is the baseline for anyone making these calls. Where the building falls under the wider scope of the Fire Safety Act 2021 or the Building Safety Act 2022, additional duties may also apply.

For facilities managers running multiple sites, the practical answer is usually a documented internal trigger list, so that project managers and contractors know in advance which works require a fresh fire risk assessment, which require a review, and which can proceed on the existing assessment with a dated note. That trigger list, kept alongside the building’s other compliance records, also gives a clean audit trail when an insurer, enforcing authority or prospective buyer asks how fire safety has been managed across the works programme. Building this discipline into wider health and safety legislation awareness across the team helps ensure decisions are consistent across sites and projects.

It is worth reviewing case studies of how other buildings have been assessed after refurbishment, as they often surface the practical issues that do not appear in generic guidance.

If you are completing refurbishment works, taking on a newly altered building, or reviewing whether existing fire safety records still reflect the building you actually operate, Acorn Safety Services (Health & Safety) can provide a competent post-works fire risk assessment, identify any gaps in compartmentation, escape routes or systems coverage, and give you a defensible position before reoccupation. Contact us to discuss the works and arrange the assessment.