More than 4.2 million rooftop solar systems have been installed across Australia. Another 478,176 home batteries went in between 1 July 2025 and 30 June 2026 alone, adding 13.58 gigawatt hours of storage in twelve months.

Almost none of that work happens during construction.

It happens afterwards. The client moves in, gets a power bill, calls a solar company, and a set of conduits goes up the outside of a house that was finished six months earlier.

Gary Higgins has spent years watching that pattern from the other side of it. He is managing director of Halcol Energy, a family run solar and battery company based on the Sunshine Coast, servicing south east Queensland from there and from a second site at Hendra in Brisbane. The business has been operating since 2010 and was a national finalist for Smart Installer of the Year at the 2025 Smart Energy Excellence Awards.

Speaking on The Good Builder Podcast, Higgins put a straightforward proposition to builders. They are not avoiding solar because it is technically hard. They are avoiding it because nobody has told them who carries the risk when it goes wrong.

Why builders leave solar out of new builds

Higgins says the split between residential retrofit work and new build work is stark.

On the residential side, batteries have gone from a fringe item to a default inclusion. He estimates Halcol now completes a small number of solar only installs each week against twenty to thirty combined solar and battery installs in the same period.

Builders are largely absent from that volume.

“It can be too hard, because you’re dealing with federal rebates, you’re dealing with Energex, and with that comes complications and regulations,” Higgins said.

That is a reasonable read of the landscape. A grid connected system in south east Queensland requires a connection application to the distributor, a certificate of electrical safety, an accredited designer and installer, and a compliant paper trail if the rebate is to be claimed. None of it is complicated for a specialist. All of it is unfamiliar to a builder who does not do it every week.

The result, Higgins argues, is that builders have decided the whole category is somebody else’s problem. Which works right up until it does not.

Who carries the warranty when the solar company disappears

This is the part Higgins is most direct about, and it is the part most likely to catch a builder out.

Australian Consumer Law. You have to warrant it. It’s your problem. If that solar company is out of business, that’s your problem.

Gary Higgins, Halcol Energy

He is broadly right, and in Queensland the position is tighter than many builders assume. Schedule 1B of the Queensland Building and Construction Commission Act 1991 implies a set of statutory warranties into every regulated domestic building contract, whether or not they appear in the document. Those warranties cover materials being good and suitable, work being carried out with reasonable care and skill, and work complying with all relevant laws. They cannot be contracted out of.

The warranty period runs for six years where a breach results in a structural defect, and one year in any other case, with a further six months available where a breach becomes apparent late in the period. The QBCC can direct rectification up to six years and six months after completion.

Critically, the homeowner’s claim sits against the contractor named on the contract. Not the trade who did the work.

Higgins points to what happens when the cheap option leaves the market.

“Does your friend know how to register the system with Energex? Do they know the compliance around claiming the STC rebate?”

His broader concern is the tail. Systems fail, inverters drop off the Wi Fi when a client changes their modem, monitoring needs reconfiguring, and warranty claims land somewhere. If the installer has gone, the homeowner works back up the chain to the only business still standing, which is usually the builder.

Halcol’s answer is a barcoded sticker on every system that routes the client to its own support, rather than to the builder. It is a small operational detail that says something useful about how the risk actually moves.

What the compliance regime actually looks like now

Higgins used the industry shorthand of a “CEC accredited” installer during the conversation. It is worth being precise, because the terminology changed and the shorthand is now out of date.

The Clean Energy Council transferred installer and designer accreditation to Solar Accreditation Australia in 2024, after the Clean Energy Regulator appointed it as scheme operator on 29 February 2024. Only accreditation issued by Solar Accreditation Australia now qualifies an installer to create small scale technology certificates. Accreditation is held by individuals, not companies, and battery work requires a separate grid connected battery endorsement on top of standard solar accreditation. The Clean Energy Council still maintains the approved product lists that determine whether the hardware itself is eligible.

For a builder, that means two separate checks rather than one. The person, and the product.

Higgins also said inspections are tightening, and that Victoria already inspects every system. That is accurate. Victoria is the only jurisdiction that legally requires an independent Licensed Electrical Inspector to inspect a solar or battery installation and issue a certificate of electrical safety before it can be connected.

His suggestion that the same regime is arriving in Queensland is not quite where things sit. Queensland has no equivalent mandatory pre energisation inspection. What has expanded is the national inspection program run by the Clean Energy Regulator under the federal battery scheme, and the numbers from that program are worth a builder’s attention.

As at 30 June 2026, the regulator had completed 3,425 battery inspections nationally, including 718 in Queensland. Of all inspections, 0.76 per cent of systems were found unsafe. A further 62.28 per cent were found substandard, meaning technically non compliant but safe to remain in operation. Only 36.95 per cent were rated adequate.

No failures were attributed to the batteries themselves. Every issue came from installation practice and workmanship. The most common cause of a substandard rating was labelling, including missing or incorrect switchboard warning labels and missing energy storage identification labels for emergency services.

An unsafe finding means the system is shut down on the spot. Installers with repeated poor results can be suspended from the scheme entirely. From 1 March 2026, installers have been required to submit geotagged and timestamped photographs of critical labelling.

That is the environment a builder is signing into when they put solar in a contract.

Where the margin actually sits

Higgins was unusually open about pricing, and made clear he was using round illustrative figures rather than real quotes.

The structure he described works like this. A homeowner walking into a showroom pays retail. A builder committing to a run of homes buys at volume pricing, because the installer can consolidate the order back through its suppliers. The gap between those two numbers is the builder’s margin, and Halcol does not undercut the builder by offering the volume price directly to that builder’s client.

On his illustrative numbers, a system quoted at six thousand dollars retail might land at around four thousand at volume. The builder retains the difference.

He also made the point that the rebate belongs to whoever claims it, and that the disclosed value of the system to a future buyer is the full installed value rather than the net cost after certificates.

Two things are worth adding that did not come up in the conversation.

The first is that certificate values are shrinking. Small scale technology certificates are calculated using a deeming period that counts the years remaining until the scheme ends in 2030, and that period drops by one every January. A system installed in 2026 generates certificates for five years. The same system installed in 2028 generates three. The discount a builder can pass on or retain is a declining asset.

The second is that any margin assumption needs to survive the warranty tail described above. A two thousand dollar margin on a system that generates three service callbacks in year two is not a two thousand dollar margin.

Solar, seven stars, and a distinction worth getting right

Higgins raised solar as a way to relieve pressure on energy performance compliance, framing it against choices like double glazing. The mechanism is real, but the detail matters and it is commonly muddled.

Under NCC 2022, a new house has to clear two separate tests. The first is a NatHERS thermal performance rating of at least seven stars, which measures the building shell only. The second is a Whole of Home rating of at least 60 out of 100, which covers fixed appliances such as heating, cooling, hot water and lighting, offset by any onsite generation and storage.

Solar does not lift the star rating. Glazing, orientation, insulation and shading do that.

Solar lifts the Whole of Home score, because generation is counted as an offset in that calculation. Apartments run to a different setting again, averaging seven stars across units with none below six, and a Whole of Home rating of at least 50.

That distinction is the difference between a specification that works and one that gets sent back by the assessor. It is also the more interesting commercial point, because it means solar can substitute for appliance upgrades in the Whole of Home budget in a way it cannot substitute for a better window.

The planning problem

The operational argument Higgins made is the least contested part of the conversation, and probably the most immediately useful.

Cabling run during construction is hidden. Cabling run afterwards is not.

“It’s external conduits on the outside. Now that we’re all in the battery space, it’s very ugly internal conduits on the inside.”

On a large townhouse project in Brisbane’s south west, he described a sequence built around the program rather than bolted onto it. Contract signed and products agreed before slabs went down. Pre wiring as soon as the frame went up. Panels installed as the roof went on, using scaffolding already on site. Then nothing until the final week, when the inverter was fitted off.

“If planned correctly, you never see us.”

He also flagged mechanical protection as a genuine defect risk. Where clearances around direct current cabling are tight, the cable has to be mechanically protected so a client hanging a picture cannot penetrate it. Metal conduit costs several times what standard conduit costs, and Higgins noted the obvious problem with cheaper alternatives, which is that a builder has no practical way to verify it was done.

Orientation is the other one. Higgins described arriving at highly specified homes, fully electrified and smart wired, with the available roof area facing south. He estimates a south facing array gives up twenty to thirty per cent of output, worse in winter. That is a design stage decision, not a solar decision, and it is made long before anyone calls an installer.

What is actually coming, and what is not

There is a widely repeated assumption in the industry that new homes will be required to be all electric with electric vehicle provisions by 2029. It is worth separating the parts of that.

Victoria is real and dated. Under Amendment VC250, planning permit applications lodged from 1 January 2024 for new dwellings, apartment developments and residential subdivisions cannot connect to reticulated natural gas. From 1 January 2027, under regulation 37A inserted by the Building and Plumbing Amendment Regulations 2025, a building surveyor cannot issue a building permit for a new home with a new reticulated gas connection. The trigger is the permit issue date, not the contract date.

The 2029 date is a different thing entirely, and it points the other way. Building Ministers agreed in October 2025 to pause further residential changes to the National Construction Code until at least mid 2029, except for essential safety and quality matters. Electric vehicle charging provisions for houses and townhouses were specifically deferred and did not make NCC 2025. Residential energy efficiency settings stay where NCC 2022 left them.

So 2029 is not a deadline for electric vehicle readiness. It is the earliest point at which the code could change again.

The commercial direction is still clear enough. NCC 2025 does mandate onsite solar photovoltaic systems on new commercial buildings. Victoria is going all electric regardless of what the national code does. And the retrofit market is telling builders what clients want well ahead of any regulator.

The Good Builder Take

The regulatory system around solar sits apart from the rest of a build. Accreditation attaches to individuals rather than companies. Products are approved separately. And in Queensland the statutory warranty follows the contract rather than the trade, for six years where a structural defect is involved.

The margin case Higgins describes is real. It rests entirely on whether the installer is still trading when the first warranty claim lands.

The point

The interesting thing about Higgins is not that he sells solar. It is his answer to what makes a good builder, which came without hesitation and without reference to solar at all.

A good builder is a planned builder.

Gary Higgins, Halcol Energy

He was talking about the call that comes on a Thursday saying the slab goes down tomorrow. But the same logic runs through everything else in the conversation. The conduit problem, the orientation problem, the compliance problem and the margin problem are all versions of the same problem, which is a decision made too late to be made well.

Solar in a new build is not a product question. It is a sequencing question, and the sequencing has to be settled at design stage, in a contract, with someone who will still be trading in six years.

Frequently asked questions

Last updated: August 2026

This article is intended for general information purposes only and does not constitute legal, financial, or professional advice. Laws, regulations, and industry requirements vary by state and territory and change over time. Builders and trades professionals should seek independent advice relevant to their specific circumstances before making business, legal, or financial decisions.

Author: TGB Editorial