Common area solar for Perth strata properties and apartment buildings

Apartment dwellers in Perth face a specific challenge: they don't own the roof, and their strata by-laws may not allow individual lots to install equipment on common property. But apartment buildings as a whole can benefit significantly from solar — on the roof powering common area electricity (lifts, corridors, parking, pool, gym).

This is a different proposition to an individual apartment owner trying to install solar for their unit's consumption.

What is common area solar?

Common area solar is a solar system installed on the body corporate's behalf, generating electricity to power shared facilities:

• Lift motors and lighting (often the largest common area load)
• Corridor and stairwell lighting
• Underground carpark lighting
• Pool filtration pump and heating
• Gym equipment and lighting
• Common area air conditioning

The solar system is owned by the body corporate (or financed through the body corporate's levy), and the savings flow to the owners' corporation — reducing the common area electricity bill and therefore the levy amounts.

How much can common area solar save?

A typical Perth apartment building of 40–60 units:

• Common area electricity: approximately $18,000–$40,000/year (varies enormously by lift count, pool, carpark size)
• Roof area available on a 10-storey building: 300–600m², supporting approximately 50–100kW of panels
• Annual generation from a 80kW system: approximately 110,000–120,000 kWh
• At A1 rate 33.26c/kWh: approximately $36,600–$39,900 annual saving potential

If common area consumption is 130,000 kWh/year and solar covers 85% of that: Annual electricity saving: approximately $28,000–$32,000

On a $120,000–$160,000 installed cost (80kW commercial-grade system, roof access, commercial metering): Payback: approximately 4–6 years

This makes common area solar one of the strongest-returning capital projects available to a strata body corporate.

What's needed to proceed

Strata motion and approval

Installing solar on common property requires a general meeting of owners with a by-law resolution. Typically:

• Ordinary resolution (50%+1 of votes): For improvements up to a certain value threshold
• Special resolution (75%): For expenditure above the threshold or changes to common property

Exact requirements depend on the strata scheme type and WA Strata Titles Act provisions. A strata manager can advise on the correct resolution type.

Roof access and structural assessment

Older apartment buildings may require a structural assessment before adding panel loading to the roof. A 80kW system at approximately 12 kg/m² adds meaningful weight — most modern concrete-frame buildings can handle this, but confirmation is needed.

Metering and tariff

Common area electricity is typically metered separately from residential lots. The solar system connects to the common area meter and reduces common area import. Western Power's commercial solar connection process applies (similar to residential but with commercial metering requirements).

For buildings with high common area demand, a larger commercial export limit may be available.

Financing options

Levy-funded: The body corporate collects a special levy from lot owners to fund the purchase. Works well if owners have capital to deploy.

Body corporate loan: Strata finance products allow the body corporate to borrow and repay from electricity savings (the savings fund the repayments).

Power purchase agreement (PPA): A third party installs and owns the solar system; the body corporate pays for the electricity generated at a rate below the grid rate. No upfront cost; benefit starts immediately.

Individual lot solar vs common area solar

An individual apartment owner wanting their own solar faces different challenges:

• Roof is common property and requires body corporate approval
• Generation credits typically cannot easily flow to an individual lot's meter
• Shared rooftop allocation is complex with multiple lots

In most WA strata schemes, individual lot solar is technically and legally challenging. Common area solar is generally simpler to implement — the body corporate owns the asset and benefits collectively.

Starting the process

For lot owners who want to push for common area solar:

1. Raise it at the AGM or request a strata committee meeting agenda item
2. Commission a feasibility assessment (solar installer does a roof survey and consumption analysis — typically free or low cost)
3. Present the feasibility results with payback analysis to owners
4. Pass the required motion
5. Proceed to installation

For strata managers and committees: Common area solar has become a standard capital improvement item in Perth strata management. Most commercial solar installers have experience with strata schemes and can provide strata-ready proposals including resolution templates.

Strata resolution requirements are set under the Strata Titles Act 1985 (WA) as amended. Consult your strata manager or a strata lawyer for current resolution thresholds. Cost estimates are indicative for Perth mid-2026.