What does electrical work in a 1960s or 1970s walk-up apartment block actually involve? These low-rise blocks, common right across the Inner West in Marrickville, Dulwich Hill, Enmore, Petersham and Leichhardt, were built to a completely different standard to a modern strata development. Expect a single old consumer mains feeding the whole block, isolation switches grouped by floor rather than one per unit, a main switchboard that predates safety switches, and a common property riser cupboard that was never designed for today's load. None of that means the building is unsafe by default, but it does mean upgrades have to work around real constraints that a newer building simply doesn't have.

⚡ Quick Answers: Walk-Up Apartment Electrical Work

Does every unit have its own switchboard? Often not fully. Many walk-ups group isolation devices by floor rather than giving each unit a fully separate board, which affects how an upgrade to one unit is scoped.
Are safety switches compulsory in these older blocks? Any circuit that gets replaced or altered has to get a safety switch as part of that work, which is how most walk-ups end up with a patchwork of protected and unprotected circuits over time.
Who pays for common property switchboard work, the owner or the strata? Common property electrical infrastructure, including the main switchboard and shared risers, is the owners corporation's responsibility. Wiring inside your own unit is yours.
Can our old consumer mains handle EV chargers or solar being added unit by unit? Not indefinitely. These blocks were sized for 1960s and 1970s loads, and enough units adding EV chargers or reverse cycle air conditioning will eventually outrun the original supply capacity.
Why is the riser cupboard always so cramped? Because access clearance requirements simply didn't exist, or were far looser, when these blocks were built, and retrofitting proper clearance into a fixed cupboard footprint is one of the harder parts of any upgrade.

1. One consumer mains, many units: how the original design actually works

A typical 1960s or 1970s walk-up, two to four storeys, no lift, eight to sixteen units, was usually connected to the street with a single consumer mains and a single point of common coupling. From there, the supply was split down to each unit through a shared arrangement rather than each unit having its own dedicated street connection. SIRNSW's rules on multiple installations require each separately metered portion of a building to be supplied from that one point of common coupling, with sealed and lockable unmetered submains running from there to each unit's meter, and every isolation point clearly labelled so a network technician or electrician can identify which unit they're isolating without guesswork.

This shared-supply design is efficient for the era it was built in, but it means the maximum demand for the whole block was calculated once, decades ago, based on 1960s or 1970s appliance loads. AS/NZS 3000's maximum demand tables scale by the number of living units on a shared supply, in bands of two to five units, six to twenty, and twenty-one or more per phase, and that calculation genuinely needs revisiting whenever the building's real-world load changes meaningfully, not just when something visibly fails. Some older blocks share their supply arrangement in a different way again, which is the exact scenario our guide to Inner West semis still sharing a switchboard with next door looks at from the two-title side of the same underlying problem.

2. Isolation devices grouped by floor, not by unit

Rather than a single main switchboard with individual isolators for every unit, many walk-ups from this era group isolation devices by floor. A tenant or owner needing to isolate their own unit for an upgrade, a fault, or an electrician's safe isolation might find the switch they need shares a group with two or three neighbouring units on the same level. This is a genuinely common surprise during a straightforward upgrade quote, because it changes what has to be coordinated (and who needs notice) before work can start on a single unit.

Where a Metering Coordinator agrees, metering per floor rather than strictly per unit is also allowed under these rules, which is part of why billing arrangements in older blocks sometimes look unusual to a new owner used to a fully individual, modern setup.

3. The main switchboard: why it can't sit inside anyone's unit

AS/NZS 3000 is specific about this for any building with multiple installations: the main switchboard cannot be located within any individual tenancy. It has to sit on common property, accessible to the owners corporation, the network and any electrician working on the building, not inside someone's lounge room cupboard because that's where the original 1960s layout happened to put the meter box. In a walk-up, this is almost always the ground floor riser or a dedicated meter room, and it's common property maintenance and upgrade responsibility under the Strata Schemes Management Act, the same principle we cover in more detail in our guide to strata electrical upgrades in the Inner West.

The access clearance rule matters here too: the standard requires a minimum 0.6 metres of clear domestic working space in front of a switchboard so it can be safely worked on. Plenty of 1960s and 1970s riser cupboards were built well before this became a settled requirement, which is why upgrading an old board sometimes means resolving a genuine physical access problem, not just swapping components.

4. Safety switches: the patchwork every old walk-up eventually develops

Safety switches, technically residual current devices rated at 30 milliamps, are mandatory on domestic final subcircuits under the current standard, including shared external lighting on common property. The catch for older buildings is that the rule doesn't retroactively require every existing circuit in an untouched building to be upgraded overnight. What it does require is that any circuit replaced or altered as part of other work picks up a safety switch for the circuits that work actually touches.

Over enough years and enough small jobs, this produces exactly the patchwork most walk-ups have today: newer circuits protected, older untouched ones not, on the same switchboard. A full main switchboard replacement is the point where this gets tidied up properly in one go, which is one of the strongest reasons an owners corporation should plan a full board replacement rather than continuing to patch a fifty-year-old board piece by piece. Our guide on how strata committees should plan a main switchboard replacement covers that decision in detail.

5. When an individual unit upgrade runs into the building's shared limits

A single unit wanting an EV charger, a reverse cycle system or an induction cooktop is usually a straightforward job on its own. The complication in a walk-up is that the unit doesn't have its own private street connection to size against, it shares one consumer mains and one maximum demand calculation with every other unit in the block. A Level 2 assessment of the shared supply, not just the unit's own wiring, is the only reliable way to know whether the building can absorb one more significant load without pushing the whole block towards capacity. This is exactly the same underlying question we cover from a slightly different angle in why power logging should happen before adding EV chargers, solar or batteries, and it applies with extra force in a shared-supply building where your neighbour's air conditioner is drawing from the same consumer mains as your new charger.

6. What if the building's supply comes from a private pole?

Most Inner West walk-ups connect to a standard street service, but a smaller number of older blocks, particularly ones on larger or corner blocks, were originally fed from a private pole rather than a conventional connection. If that's your building, ownership, maintenance and upgrade responsibility for that pole sit with the owners corporation as a shared asset, and any work on it is genuinely different scope to switchboard work inside the building. Our sister site's guide to private power pole ownership types and rules is worth a read if you're not sure which category your building falls into.

How High Demand Electrical helps

We're a licensed local team, not a call centre, and we've walked into more than a few Inner West walk-ups where the switchboard, riser and consumer mains hadn't been properly reassessed since the building went up. We'll trace how your block's shared supply is actually arranged, tell the owners corporation honestly whether the main switchboard needs a full replacement or a genuine patch will hold for now, and scope individual unit upgrades against the real capacity of the shared consumer mains rather than assuming it in isolation. If you're after an electrician near you in Sydney's Inner West who understands older strata buildings specifically, that's a large part of what we do every week.

Walk-Up Apartment Electrical FAQs (Sydney)

Who is responsible for common property wiring in a walk-up, the owners corporation or individual owners?

Common property electrical infrastructure, including the main switchboard, shared risers and submains, is the owners corporation's responsibility under the Strata Schemes Management Act. Wiring and circuits inside your own unit are yours. See our strata electrical upgrades guide for the full breakdown.

Can one unit's renovation trigger safety switch upgrades for other units?

Not directly, but if the renovation involves work on shared submains or the main switchboard, it can surface safety switch gaps affecting other units that then need to be addressed as part of that broader work.

How do we know if our building's consumer mains can take more EV chargers?

A Level 2 load assessment of the shared consumer mains, based on real logged demand rather than the original 1960s or 1970s calculation, is the only reliable answer. See power logging before adding EV chargers, solar or batteries.

Is it worth replacing the whole main switchboard instead of patching it again?

For a board that's had decades of piecemeal repairs, a full replacement usually resolves the safety switch patchwork, access clearance problems and ageing components in one project rather than continuing to spend on a board that's reaching the end of its practical life. Our switchboard replacement planning guide walks through how to budget and sequence that.

Get Your Walk-Up's Switchboard Properly Assessed

Get a switchboard upgrade quote or call 0402 559 777 and we'll assess your building's shared supply, main switchboard and common property wiring before any scope or pricing is locked in. Every job still needs a site assessment first.

Electrical Work in 1960s and 1970s Walk-Up Apartment Blocks: What Inner West Owners Need to Know