Fire Safety in Occupied Buildings During Refurb: The Extra Rules

‍‌​​‌‌‌​​‌​‌‌​​‌​​‌‌​​‌​‌​​​‌‌​​​‍Fire safety on a live job in someone's home or workplace is not "same as a normal site but indoors" -- the law expects you to protect the people still living and working there, not just your own team.

4.27.1 The rules you're working under

Two regimes bite at the same time:

• Construction safety -- CDM and HSE's Fire safety in construction (HSG168) cover fire on construction work generally.
• Fire safety law for occupied buildings -- the Regulatory Reform (Fire Safety) Order 2005 ("Fire Safety Order") covers almost all non-domestic premises and the common parts of blocks of flats.

Key points from the Fire Safety Order

• Every occupied building must have a Responsible Person (RP) -- usually the owner, landlord, managing agent, or employer.
• The RP must:
  • Do and keep up a fire risk assessment covering how the building is actually used.
  • Keep escape routes usable, alarms and detection working, and fire separation (doors, walls) in place.
  • Review and update the assessment when things change -- including building work.

When you come in as the contractor

• You're responsible for your own work and people, but you also mustn't wreck the existing fire precautions that protect residents/staff without agreeing how they'll be replaced or temporarily managed.
• On commercial and common-parts work, your method statements and RAMS should reflect the Fire Safety Order duties (escape routes, alarms, compartmentation) as well as CDM.

The stakes are higher than property damage

If your work causes a fire in an occupied building and someone is injured or killed, you're potentially looking at gross negligence manslaughter (for individuals) or corporate manslaughter (for companies) -- not just an insurance claim. That's why permits, precautions and agreements with the RP aren't optional extras.

4.27.2 New duties for higher-risk residential buildings

On tall or "higher-risk" residential buildings, the Fire Safety Act 2021 and Building Safety Act 2022 crank the pressure up further.

Fire Safety Act 2021

• Clarified that the Fire Safety Order explicitly covers:
  • The building structure and external walls (including cladding, balconies, insulation).
  • Flat entrance doors opening onto common parts.
• RPs must consider these in the fire risk assessment and maintain them, including during refurb and remediation.

Building Safety Act 2022 (high-rise / higher-risk residential)

• Sets up a Building Safety Regulator and a tougher regime for higher-risk buildings (generally 18m+/7+ storeys with residential).
• For major refurb/remediation, there's now a "gateway" system -- work often has to be approved by the regulator before starting and on completion.
• Dutyholders (client, principal designer, principal contractor) have extra duties around competence, reporting safety occurrences, and keeping a "golden thread" of information.

For you on the tools, the headline is: on blocks of flats and higher-risk residential buildings, people above and below you rely heavily on fire separation, doors and alarms -- and the law now expects those to be controlled and recorded properly during works, not just "we'll patch it later."

4.27.3 Hot work and hot work permits

Hot work is anything that creates flames, heat or sparks that could start a fire -- welding, grinding, gas cutting, bitumen boilers, some soldering, even certain paint stripping.

In occupied or non-designated areas, you should only be doing hot work under a hot work permit:

A hot work permit is a formal, written authorisation that

• Describes exactly what hot work, where, and when.
• Confirms the fire risk assessment and method statement have been done.
• Lists pre-work checks: remove combustibles, cover surfaces, provide extinguishers, brief people.
• Sets fire watch arrangements, including how long after work finishes someone checks for smouldering (often at least 60 minutes).
• Is issued by someone competent and in control (RP, building manager, principal contractor).

You need a permit for hot work in

• Occupied buildings where the area isn't a permanent, fire-resistant "welding bay".
• Commercial premises in use, schools, hospitals, warehouses, care homes -- basically anywhere with people and combustibles.
• Historic buildings (which are particularly vulnerable) -- guidance says avoid hot work if at all possible in these.

If you're being asked to do hot work with no permit, no prep and no fire kit, that's a big red flag.

4.27.4 Keeping escape routes and alarms usable

This is where most refurb jobs in occupied spaces go wrong.

From HSE and Fire Safety Order guidance:

Keep escape routes open and safe

• Corridors, stairs, landings, flat entrance lobbies -- no blocking them with materials, dust sheets, rubbish, or plant.
• If you have to take something out of use temporarily (e.g. one staircase), you need an agreed plan with the RP -- maybe temporary escape signage, different route, or limiting occupancy.

Maintain fire detection and alarms

• If you've got detectors in the work area, don't just tape them up or take heads off without agreement; you're removing part of the building's life-safety system.
• If alarms must be silenced or isolated (e.g. for dust-generating work), there should be:
  • A written permit/authorisation,
  • A clear time window,
  • Temporary arrangements (e.g. portable detectors, fire watch) if needed.

Protect compartmentation

• Fire doors mustn't be wedged open "just for a bit".
• If you're drilling, chasing or opening up fire-rated walls, ceilings or risers, you're breaching compartmentation -- that has to be fire-stopped again to at least the original standard.

Communal area working hours

Many managing agents and RPs restrict noisy, dusty or fire-risk work to specific hours in blocks of flats -- often to manage the overlap between your work and residents using escape routes. If you ignore their restrictions, you're undermining the RP's fire management plan and they can stop your work. Check before you start, not after you get a complaint.

HSE's general fire guidance explicitly says that, in occupied buildings like offices, your work must not interfere with existing escape routes, separation, alarms, dry risers or sprinklers.

4.27.5 Real-world scenarios

1) House refurb with family living upstairs

Example: ripping out and refitting a kitchen while the family are still sleeping in the bedrooms.

You need to think about:

Escape routes:

• Can they still get out if a fire starts in your work area?
• Do you block the hall/stairs with gear, or leave them clear?

Ignition sources:

• Use of LPG torches, grinders, temporary heaters -- where are you putting cylinders, how are you supervising them?

Alarm/smoke detection:

• If you're taking down mains-linked smoke alarms temporarily, what's in place instead? Battery alarms in bedrooms? Clear agreement on reinstatement?

There's no formal Fire Safety Order duty in a single-family dwelling, but your duty of care at common law still applies -- if your work causes a fire and you've been sloppy, expect questions from insurers, the fire brigade, and potentially the police. Your insurance policy conditions almost certainly require fire precautions during work. So even without the FSO, it's not a legal vacuum.

2) Working in a shop/office during trading hours

Here the Fire Safety Order absolutely applies.

You can't:

• Leave cables, leads, or materials as trip hazards on escape routes.
• Block fire exits or cover exit signs.
• Disable alarms or sprinklers without agreement and controls.

The RP (often the employer or landlord) must update their fire risk assessment to reflect the work -- and you are part of that conversation.

3) Flat in a block (other residents above/below)

Here you might be working:

• Inside one flat,
• On common parts (corridor, stair),
• Or on the structure/external walls.

Fire Safety Act and Building Safety Act mean:

• The RP must consider the external walls, structure and flat doors in their risk assessment.

• If you mess with:

  • Flat entrance doors,
  • Service risers,
  • Penetrations through floors or walls,
  • External walls (cladding, insulation),

  you are affecting the fire strategy for the whole building.

You must:

• Agree in advance how compartmentation will be opened and properly re-sealed.
• Tell the RP if you encounter or create new fire risks (e.g. cavities, missing fire stopping) during the works.

4.27.6 Discovering existing fire safety failures

This happens more often than people admit. You open up a wall or ceiling in a block of flats and find zero fire stopping, missing cavity barriers, or fire doors that don't meet any standard.

What to do

• Don't just close it back up and pretend you didn't see it. You now know about a fire risk to residents.
• Tell the Responsible Person / building manager immediately -- in writing, not just a passing comment on site.
• On higher-risk buildings under the Building Safety Act, the principal contractor or accountable person may have a legal duty to report certain safety occurrences to the Building Safety Regulator.
• You are not obliged to fix someone else's problem at your own cost, but you are expected to flag it. If you knowingly conceal a fire safety defect in a residential building and someone later dies in a fire, the questions will be brutal.

Keep a record of what you found, when, and who you told. A photo and a short email to the RP takes two minutes and could matter enormously.

4.27.7 Alarms, temporary detection and breaching fire-stopping

Disabling alarms for dust

If you need to isolate a detector or a whole zone:

• Don't just tape over it and forget.
• Agree with the RP/building manager:
  • What zone will be isolated and when.
  • Who is in the building at that time.
  • Whether extra steps are needed (temporary detectors, additional fire watch, restricting work to certain hours).
• Make sure it's re-enabled and tested as soon as the work that causes false alarms is done.

Temporary detection / suppression

On bigger refurb jobs -- especially where existing systems are down -- it may be appropriate to:

• Install temporary wireless detectors.
• Provide extra extinguishers (and make sure people know how to use them).
• Run a waking watch or increased patrols in high-risk periods.

That's normally a joint decision between the RP, the principal contractor and the fire risk assessor.

Cost note on waking watches: these are expensive -- often thousands of pounds per week -- and the cost usually falls on the client or freeholder. If your work triggers a waking watch requirement, have that conversation before you start, not after the alarms go down. Nobody wants a surprise bill.

Breaching compartmentation

If you:

• Drill through a fire-rated wall or floor,
• Remove a fire door or frame,
• Run services through fire-stopping,

you are required to:

• Make sure any opening is fire-stopped with suitable materials, properly installed.
• Replace fire doors with third-party certificated fire door sets -- not just any door with an FD30 label. This requirement has tightened significantly post-Grenfell; certificated sets come with evidence of testing and a chain of custody from manufacturer to installation.
• Record what's been done -- many RPs now expect fire-stopping logs with photos and product details.

Leaving gaps because "we'll come back later" is how smoke and fire get between flats or from a riser into a corridor.

4.27.8 LPG, hot work and insurance

LPG and hot work in an occupied building are high-risk -- and insurers know it.

Hot work

As above, you should have a permit system with proper controls.

LPG

Cylinders should be:

• Kept to the minimum needed on site.
• Stored upright, secure, away from escape routes and ignition sources.
• Valves closed when not in use.
• Never leave blowtorches or burners lit and unattended -- especially not in voids or roof spaces.

Insurance angle

• Many contractors' and property policies have conditions about hot work and fire precautions -- fail to follow them and cover can be refused for a fire loss.
• HSE and fire authorities are cracking down on poor fire precautions on construction work, including refurb in occupied buildings.
• If you haven't looked at the hot-work clause in your policy, it's worth five minutes before you get the torch out.

What to do next

On your next job in an occupied building:

• Before you start, ask: Who is the Responsible Person for fire safety here? (landlord, building manager, client).
• Walk the escape routes you might affect and agree how you'll keep them usable.
• If you're planning hot work, insist on a hot work permit and make sure you follow it -- prep, fire watch, and checks afterwards.
• If you're going to open up or penetrate fire-rated construction, agree how it will be fire-stopped and how it's recorded.
• Never disable alarms or sprinklers without written agreement on how long for and what's in place instead.

A short conversation and simple permit can save you from being "the contractor who burnt the building down."

Sources

• Regulatory Reform (Fire Safety) Order 2005 -- legislation.gov.uk/uksi/2005/1541/contents/made -- the main fire safety law for non-domestic premises and common parts of residential buildings.
• Fire Safety Act 2021 -- legislation.gov.uk/ukpga/2021/24/contents/enacted -- extending the Fire Safety Order to structure, external walls and flat entrance doors.
• Building Safety Act 2022 -- legislation.gov.uk/ukpga/2022/30/contents/enacted -- new regime, gateway process and dutyholder responsibilities for higher-risk residential buildings.
• HSE -- HSG168: Fire safety in construction -- hse.gov.uk/pubns/books/hsg168.htm -- requirements for fire precautions during building work.
• HSE -- General fire safety guidance -- fire precautions and escape routes during construction and refurbishment.
• Home Office fire safety guides -- gov.uk/government/collections/fire-safety-law-and-guidance-documents-for-business -- guidance for Responsible Persons under the Fire Safety Order.
• CHAS and Historic England -- hot work permit-to-work system guidance.
• Fire door certification -- post-Grenfell guidance on third-party certificated fire door sets from industry bodies including BWF Fire Door Alliance.

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