Fire Safety Order 2005: What It Means for Your Jobs

‍‌​​‌​​‌‌​​​​‌​‌​‌​​‌​​‌‌​‌‌‌‌​​​‍For small builders and main contractors (England & Wales)

Last reviewed: March 2026

This is the bit that sits after Part B. Building Regs cover how you build it; the Fire Safety Order covers how it's managed once people are living or working in it.

1. What the Fire Safety Order actually is

The Regulatory Reform (Fire Safety) Order 2005 ("FSO") is the main fire safety law for non-domestic premises and the common parts of residential buildings - stairwells, lobbies, corridors, plant rooms, bin stores etc.

It puts duties on a "responsible person" (usually landlord, freeholder, managing agent or employer) to:

• Carry out a fire risk assessment.
• Put in and maintain appropriate fire safety measures.

Inside a single private dwelling (one family house or a flat interior) the Order doesn't apply. As soon as you're into common areas or non-domestic use, it does.

2. Where it touches your work

You feel the FSO on:

• HMOs and shared houses - common halls, stairs, kitchens etc. are covered; the responsible person must manage alarms, doors, routes, signage.
• Blocks of flats / maisonettes - the lobby/stair/landing/bin store areas are under the Order; flats themselves are mostly covered via Housing Act/Part B.
• Mixed-use buildings - shops/offices with flats above; the non-domestic bits and shared escape routes fall under the FSO.

On those jobs, you are:

• Building/altering the physical fire precautions (Part B stuff - doors, walls, alarms).
• The client/owner/agent then has to keep them in good order and risk-assessed under the FSO.

So if you butcher compartmentation or fit junk fire doors, you've screwed their Building Regs and their ability to comply with the Fire Safety Order.

3. How it works in practice (builder's view)

Under the FSO the responsible person must:

• Do a fire risk assessment of the premises (often a small block/HMO specialist or fire-risk assessor does this).
• Keep escape routes clear and protected.
• Provide and maintain alarms, emergency lighting, signage, fire doors etc., as appropriate.
• Review and update the assessment if things change (works, layout changes, incidents).

Your bit

• Build to Part B so the risk assessor has decent bones to work with - proper fire doors, closers, strips/seals, compartmentation, fire-stopped services, correctly routed alarm cabling.
• Don't compromise existing fire precautions when you're in doing other work (e.g. drilling service holes and not fire-stopping them, wedging/removing closers, hacking at riser walls).
• If you alter fire strategy (e.g. changing from stay-put to full evacuation, or reconfiguring lobbies/stairs), expect the client's fire-risk assessor and/or fire service to get involved.

4. Typical scenarios

Converting a house to an HMO

• You: install fire doors, alarms, emergency lighting, compartmentation and signage in line with Part B and LACORS-style guidance.
• Client: gets a fire risk assessment done and keeps systems maintained under the FSO.

Refurbishing common parts of a block of flats

• You: replace doors, ceilings, riser walls, maybe upgrade alarms or lighting.
• Client: must ensure the end result still supports the fire strategy (often "stay put") and is signed off in the fire risk assessment.

Shop fit-out under flats

• You: fit new ceilings/partitions/services in the shop - don't compromise the escape route or compartmentation that protects flats.
• Responsible person: updates their risk assessment and may argue with you if you've turned their compartment wall into Swiss cheese.

5. Where small builders get dragged in

You're not the "responsible person", but you can still cause FSO problems by:

• Removing or disabling fire doors/closers and not reinstating them properly.
• Running services through walls/floors and not fire-stopping penetrations.
• Boxing in or removing detectors, call points, sounders or emergency lights.
• Adding combustible linings to escape routes (e.g. timber cladding in a tiny HMO stair).

If your work ends up in a fire risk assessment as a deficiency, the owner will be back on the phone asking you to fix it - sometimes with the fire service already involved.

6. What to do on FSO-relevant jobs

When you're working on HMOs, common parts or mixed-use:

• Ask who the responsible person is and whether they have a current fire risk assessment.
• Work to Part B and LACORS-type guidance (for HMOs) and don't improvise fire measures.
• Before you change anything that obviously affects fire safety (doors, lobbies, escape routes, compartment walls, risers), tell the client they need their fire-risk assessor in the loop.
• Hand over any fire-related certificates, door schedules, alarm test sheets etc. clearly - they become part of the FSO paperwork.

If you're clear on where your responsibility stops (providing compliant physical measures) and theirs starts (ongoing assessment and management), you'll avoid most messy arguments.

This page is a general guide for small builders and main contractors. It doesn't replace the Regulatory Reform (Fire Safety) Order 2005, official guidance or professional fire-risk advice. Always check the latest government/fire service guidance, and involve a competent fire-risk assessor where your works affect escape routes or common parts. SiteKiln does not provide legal, financial or tax advice. All content is for general information purposes only. Always seek professional advice for your specific situation.

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