Are Steel Frames Electrically Safe?

Framing materials, and building materials in general, will either conduct or resist electricity. So, the question is whether to conduct or resist electrical current when choosing your framing material.

The higher the material's conductive properties, the less likely structural damage will occur.

Steel, for instance, with its low resistance (high conductivity) to electrical current, will allow the electricity to run through it easier than a high-resistance material like a timber frame.

With steel's high conductivity, you may ask yourself, doesn't that make it dangerous? Steel frames used in modern construction are generally considered safe from an electrical standpoint due to proper grounding and safety measures. The risk of electrical hazards is significantly reduced in steel-framed structures compared to those with timber frames, where broken or pierced wires can remain live and pose potential safety risks. Implementing circuit-breaking safety devices in new housing further minimises the chances of encountering live electrical components. This emphasises the importance of using steel frames, as they contribute to a safer overall electrical environment in buildings.

Australian regulations mandate that steel frames in homes are properly earthed to the ground. This safety measure ensures that if a steel frame is subjected to an electrical current, the electricity will be conducted safely into the earth, minimising the risk of electric shock. Moreover, all houses in Australia are required by law to have residual current devices (RCDs) installed. These devices provide an extra layer of protection against electric shocks and potential electrical fires by rapidly cutting off the power supply when irregularities are detected.

What about lightning? Steel frame homes are generally less susceptible to lightning's damaging effects than conventional framing materials. Steel's conductive properties create a more direct path for lightning energy to be conducted into the ground, reducing the risk of destructive discharge within the frame or cladding. This positive earth created by the steel frame helps dissipate the lightning's energy harmlessly, making steel-framed homes a safer option in areas prone to lightning strikes.

There's a reason why you should never stand under a tree in a lightning storm!

Steel Frames = Safety

In New South Wales, safety switches like Residual Current Devices (RCDs), Earth Leakage Circuit Breakers (ELCBs), proper earthing, and electrical leak containment are required components of the building code for all residential properties, including steel-framed houses. These measures ensure the safety of occupants and prevent electrical accidents, shocks, and fires.

The specific requirements for electrical safety in buildings, including the installation of safety switches and proper earthing, are outlined in the Australian Standard AS/NZS 3000:2018, also known as the Wiring Rules. This standard provides guidelines for designing, installing, and verifying electrical installations.

In NSW, the National Construction Code (NCC) is adopted, which includes the Wiring Rules as a fundamental component. The NCC sets the minimum standards for safety, health, amenity, and sustainability in the design and construction of buildings.

Here's a breakdown of the electrical safety measures required in NSW:

RCDs and ELCBs: These devices must be installed to protect against electrical shock and faults. RCDs monitor the flow of current and quickly disconnect the power if an imbalance is detected. ELCBs provide similar protection by detecting leakage current.
Earthing: Proper earthing is essential to provide a safe path for electrical faults to dissipate into the ground, preventing the buildup of dangerous voltages in metal parts of the house.
Electrical Leak Containment: This refers to proper insulation and containment of electrical systems to prevent leaks and ensure that current flows along the intended paths. Generally, steel frames are manufactured with service holes (to run wiring through) covered by plastic electrical grommets that will save any wiring from getting damaged and leaking current.

It is essential to ensure that the steel frame is designed and installed correctly to comply with the relevant safety regulations and building code. This requires careful consideration of the structural design and the use of appropriate materials and techniques during construction.

Are Steel Frames Electrically Safe?

Framing materials, and building materials in general, will either conduct or resist electricity. So, the question is whether to conduct or resist electrical current when choosing your framing material.

Steel Frames = Safety

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