Winter Fire Risks for Commercial Buildings: Prevention Strategies That Actually Work

Search "winter fire safety" and you'll find a flood of advice about electric blankets, hot water bottles, and keeping curtains away from heaters. Useful if you're a homeowner. Largely irrelevant if you're managing a commercial office, a strata complex, or an industrial facility.

Commercial buildings face a different set of winter fire risks and most generic advice doesn't address them at all.

Fire and Rescue NSW responds to approximately 4,500 residential fires each year, with electrical appliances and faults causing almost 40% of home fires. In NSW specifically, the rising number of fire cases during winter indicates that heating requirements are more likely to contribute to electrical fires and that pattern doesn't stop at the front door of a commercial building. It scales up, across more floors, more occupants, and more electrical infrastructure.

This guide covers the winter risks that actually matter for building owners, facilities managers, and strata committees and the prevention strategies that hold up under scrutiny.

Why Winter Changes Your Building's Risk Profile

Three things happen simultaneously every winter in a commercial building, and each one increases fire risk on its own. Together, they compound.

Electrical Load Increases

Heating systems, whether centralised HVAC, portable heaters in individual offices, or supplementary heating in common areas — draw significantly more current than in warmer months. Circuits and switchboards that comfortably handle summer loads can run hot under winter demand, particularly in older buildings where the electrical infrastructure wasn't designed for current usage patterns.

Maintenance Gaps Become More Dangerous

A loose connection or a degraded insulation point that sits quietly through summer can become an ignition source once the same circuit is carrying winter heating load. This is precisely why thermal imaging inspections are most valuable when conducted heading into winter — they catch faults before increased load turns them into fires.

Occupant Behaviour Changes

Portable heaters appear in offices that don't have one in summer. Doors and windows close, reducing ventilation. Smokers congregate in sheltered areas near building entrances. None of these are inherently hazardous, but each one shifts risk in ways that a building's fire safety systems need to account for.

Winter Fire Risks Specific to Commercial and Strata Buildings

Portable Heater Proliferation

Unlike a home, where heating is usually centrally managed, commercial buildings often see an uncontrolled spread of portable heaters as individual tenants, staff, or residents respond to cold offices and common areas. These units are frequently plugged into powerboards alongside other equipment, positioned too close to furniture, paper storage, or curtains, and left running unattended overnight or over weekends.

Prevention: Establish and communicate a clear building policy on portable heater use, including approved types, placement requirements, and a ban on powerboard use for heaters. High-draw appliances such as heaters can easily exceed what a standard powerboard is designed to handle. Heaters belong on dedicated wall outlets, not daisy-chained through extension boards.

Electrical Infrastructure Under Strain

Office buildings, retail premises, and strata common areas all see a seasonal spike in electrical demand — heating, increased lighting hours, and additional equipment. Deteriorated or poorly fitted wiring becomes a hazard over time, resulting in insulation failure and excess heat, which may lead to sparks that ignite fires if combustible materials are nearby.

Prevention: This is exactly where a pre-winter thermal imaging inspection earns its cost. Scanning switchboards and distribution boards before peak winter load reveals hotspots, overloaded circuits, and failing connections while they're still manageable repairs — not emergencies. Updating switchboards and installing safety switches on every circuit can dramatically reduce risk.

Lint, Dust and Ventilation Blockages

Commercial laundries, gyms with on-site facilities, and any building with mechanical ventilation or exhaust systems face a less obvious risk: dust and lint accumulation. An exhaust fan can slowly collect lint over time, creating a hidden fire hazard. When the fan motor is trying to turn but it's clogged, it gets hot and that heat can ignite the lint. In commercial settings, this applies to laundry exhaust systems, kitchen extraction in food service tenancies, and mechanical plant rooms with reduced winter ventilation due to closed dampers.

Prevention: Include exhaust and ventilation system cleaning in your winter pre-season maintenance checklist, not just your annual service. Regular cleaning prevents flammable build-up in roof spaces and plant areas.

Halogen and Older Lighting Systems

Many commercial and strata buildings still operate older lighting installations, including halogen downlights in common areas, foyers, and plant rooms. Old halogen downlights can exceed 300 degrees and smoulder nearby timber or insulation for years undetected. Increased winter lighting hours mean these fittings run for longer periods, increasing cumulative heat exposure to surrounding materials.

Prevention: A lighting audit ahead of winter — checking fitting condition, clearances from insulation and timber, and considering LED replacement for high-risk halogen installations — closes a risk that's easy to overlook because it's been "fine for years."

Lithium-Ion Battery Charging in Enclosed Spaces

Winter brings reduced natural ventilation as windows and doors stay closed, and increased indoor charging activity for e-bikes, e-scooters, and power tools as outdoor storage becomes less appealing. These fires involve thermal runaway, making them incredibly difficult to extinguish.

Prevention: If your building doesn't already have a clear policy on where lithium-ion devices can be charged and specifically prohibiting charging in stairwells, near fire exits, and in poorly ventilated storage areas — winter is when that gap becomes most dangerous.

The Compliance Angle: Why Winter Readiness Matters for Your AFSS

Beyond the immediate safety case, there's a compliance dimension that's easy to overlook.

Since 13 February 2026, AS 1851-2012 requires structured, documented maintenance across every essential fire safety measure in your building. A pre-winter inspection cycle, covering electrical systems, fire detection, emergency lighting, and passive fire protection — isn't a separate seasonal exercise. It's an opportunity to front-load your annual maintenance schedule ahead of the highest-risk period of the year, while simultaneously strengthening your AFSS documentation.

Building owners must ensure that maintenance is conducted by competent persons, and that all systems and equipment remain operational at all times by undertaking remedial works associated with identified defects promptly. Buildings that wait until a defect causes a problem, rather than catching it during a scheduled pre-winter check — are taking on risk that's entirely avoidable.

It's also worth remembering that not every essential fire safety measure is covered by AS 1851-2012. Some types, such as emergency exit lighting, are maintained to the standard specified in the Fire Safety Schedule (FSS) or to their original design, typically AS/NZS 2293. A genuinely thorough pre-winter audit needs to span both frameworks, not just the AS 1851 measures.

A Practical Pre-Winter Checklist

Here's what a structured pre-winter readiness assessment should cover, regardless of whether your building is a commercial office, a strata residential complex, or an industrial facility:

• ☐ Electrical systems — Thermal imaging scan of main switchboards and distribution boards. Visual inspection of circuits carrying heating load. Confirmation that safety switches (RCDs) are fitted and tested on every circuit.

• ☐ Heating equipment — Review of any building-supplied heating systems for service currency. Communication of an approved portable heater policy to tenants, staff, or residents.

• ☐ Ventilation and exhaust — Cleaning of laundry, kitchen, and plant room exhaust systems. Inspection of dampers and ductwork for lint or dust build-up.

• ☐ Lighting — Visual and thermal check of halogen or older lighting fittings, particularly those near insulation, timber framing, or stored combustibles.

• ☐ Emergency systems — Confirmation that your six-monthly emergency lighting discharge test is current heading into winter, when power outages from storms are more frequent.

• ☐ Battery and device charging — Review and, if necessary, update your building's policy on e-bike, e-scooter, and lithium-ion device charging in common areas and basements.

• ☐ Documentation — Confirmation that your on-site AS 1851-2012 logbook is current and that any defects identified during the pre-winter check are logged, categorised, and scheduled for rectification.

None of this needs to be a separate compliance exercise. For most buildings, it's simply a matter of bringing your scheduled annual or six-monthly servicing forward to align with the start of the cooler months, so the building enters its highest-risk period with everything already checked, not waiting to be checked.

The Bottom Line

Winter doesn't create new fire risks out of nowhere. It exposes the ones that were already there — the loose connection, the overloaded circuit, the lint-clogged exhaust fan, the heater on the wrong powerboard, and gives them the conditions to become a problem.

The buildings that get through winter without incident aren't the ones with the most expensive systems. They're the ones that checked everything before the cold weather arrived, not after something went wrong.

EverSure Fire Protection provides pre-winter readiness assessments, thermal imaging, and AS 1851-2012 compliant maintenance across commercial, industrial, and strata properties throughout Greater Sydney. If your building hasn't had a pre-winter check this year, there's still time to get ahead of it.

📞 02 8212 4801 | 02 9560 1844

✉️ info@eversurefire.com.au

Disclaimer: This article provides general information about winter fire safety risks for commercial and strata buildings in Australia as of June 2026. It is not engineering or building advice. Always consult a qualified, licensed fire safety professional for guidance specific to your property.

❓ FAQ

When should a building get a pre-winter fire safety inspection?

Ideally in autumn, before peak heating season begins — this gives time to action any defects (such as overloaded circuits or faulty fittings) before the coldest months arrive.

Does AS 1851-2012 require a separate winter inspection?

No — there's no standalone "winter inspection" requirement. The opportunity is to bring forward your existing scheduled annual or six-monthly servicing to align with the start of the cooler months, rather than waiting for routine timing.

Why is thermal imaging particularly useful in winter?

Thermal imaging detects heat patterns invisible to the eye — overloaded circuits, loose connections, and failing insulation — which are far more likely to become ignition sources once winter heating load pushes them past their limits.

Are emergency exit lights covered by AS 1851-2012?

Not always. Many emergency lighting systems are maintained to AS/NZS 2293 or to the requirements set out in the building's Fire Safety Schedule, so a full pre-winter audit should check both frameworks.

What's the biggest overlooked winter fire risk in commercial buildings?

Portable heater misuse — particularly heaters plugged into powerboards rather than dedicated wall outlets, and left running unattended in offices or common areas.