Security Screen Windows and Bushfire Protection

May 21st, 2026

Key Takeaways

• Ember attack risk: Windborne embers are the primary cause of home ignition during bushfires in Australia, security screens are the first line of defence for openable windows and doors
• Mesh requirement: AS3959 requires a maximum 2mm aperture to block embers, CommandeX SecureView mesh aperture is 1.575mm, exceeding this requirement
• Material: 316 marine grade stainless steel mesh, corrosion resistant and ember resistant, superior to 304 grade in harsh environmental conditions
• BAL rating: CommandeX SecureView is independently tested and compliant up to BAL-40
• BAL-FZ: Requires fire shutters in addition to security screens, security screens alone cannot achieve BAL-FZ compliance as a standalone solution

The real threat during a bushfire isn’t the fire front

Most people picture a wall of flames when they think about bushfire risk. The reality is different. Over 90% of home losses in Australia are caused by ember attacks, burning material carried by wind ahead of the main fire front are responsible for the majority of home losses. 

Embers can travel kilometres ahead of the fire. They land on roofs, in gutters, against fences and on window sills. They find gaps. And when they find a weak flyscreen, they go straight through it.

How embers enter your home

A standard flyscreen offers almost no protection during a bushfire. The aluminium or fibreglass mesh used in standard flyscreens has a low melting point, direct ember contact can melt or burn through it, creating an opening.

Once inside, an ember landing on a timber windowsill or curtain is enough to start a fire from within the home while the main fire front is still kilometres away.

The gaps that matter most are openable windows and doors. These are the weak points in any home’s ember defence.

What AS3959 requires for ember protection

Australian Standard AS3959 is relation to requirements of construction of buildings in bushfire prone areas that are for window and door screening in bushfire risk zones. The key requirements for openable windows:

• Maximum mesh aperture of 2mm to block windborne embers
• Material must be steel, bronze or stainless steel, aluminium mesh is not acceptable at BAL-40
• Screen must be fitted to the openable part of the window or door

These requirements apply from BAL 12.5 through to BAL-40. At BAL-FZ, the most extreme rating, fire shutters are required. Security screens alone cannot achieve BAL-FZ compliance regardless of the product used.

How CommandeX security screens protect against ember attack

CommandeX SecureView Eclipx and SaltWaterSeries security screens are independently tested and satisfy AS3959:2018 from BAL 12.5 through to BAL-40.

The 316 marine grade stainless steel mesh has a 1.575mm aperture, below the 2mm maximum required by AS3959. The woven stainless steel construction handles ember contact without melting or burning through, maintaining the barrier between the ember and the inside of your home.

316 marine grade also contains molybdenum, providing superior resistance to the harsh environmental conditions common in bushfire prone areas — heat, humidity and salt air in coastal bushfire zones.

Coastal homes in bushfire prone areas – a double threat

Many of Australia’s most bushfire prone areas are also coastal, the NSW South Coast, Queensland hinterland and parts of Victoria all face both salt air corrosion and bushfire risk simultaneously.

For these properties, CommandeX SaltWaterSeries is the appropriate specification. It satisfies AS3959:2018 BAL 12.5 through to BAL-40 and provides additional frame coating independently tested to 3,000 hours under AS2331.3.1, the neutral salt spray test for metal coatings. Backed by a 20 year extended warranty.

A standard 316 marine grade screen is not sufficient for the frame in extreme coastal conditions. SaltWaterSeries is the only dedicated extreme coastal security screen product in Australia.

Frequently Asked Questions

What is an ember attack during a bushfire?

An ember attack occurs when burning material is carried by wind ahead of the main fire front sometimes kilometres ahead. Embers land on and around homes starting spot fires before the main fire arrives. Ember attacks are responsible for the majority of home losses during Australian bushfires not the fire front itself.

Do security screens protect against ember attacks?

Yes, SecureView and SaltWaterSeries security screens are independently tested to AS3959:2018 and satisfy bushfire attack level requirements from BAL 12.5 through to BAL-40. The 1.575mm aperture stainless steel mesh stops embers from penetrating windows and doors while standard fly screens can melt or allow embers through.

What is the difference between BAL 40 and BAL-FZ?

BAL 40 is very high risk, exposure to flames is possible but not certain. Security screens meeting AS3959:2018 can satisfy BAL 40 requirements. BAL-FZ is extreme risk direct flame front exposure, where fire shutters are required. CommandeX security screens satisfy BAL 12.5 through to BAL-40 but are not rated for BAL-FZ.

Can SaltWaterSeries be used in coastal bushfire prone areas?

Yes, SaltWaterSeries is specifically recommended for coastal properties in bushfire prone areas. It satisfies both AS3959:2018 BAL 40 bushfire requirements and provides additional corrosion resistance for coastal environments with frame coating tested to 3,000 hours under AS2331.3.1. Backed by a 20 year extended warranty.