Commercial Solar

Can Your Roof Handle Commercial Solar? What We Check

Guide · Commercial solar & battery · ~5 min read

Before a single panel goes up, your roof has to be up to the job. Here's what our in-house team looks at to work out whether your building is solar-ready, and what to do if it isn't quite there yet.

Why the roof assessment comes first

A commercial solar system is a long-term fixture. It needs to sit on a roof that can carry the extra load, shed water properly and stay sound for decades. That's why we treat the roof review as the foundation of the whole project, not an afterthought.

Skipping this step is how you end up with leaks, voided warranties or panels that have to come off and go back on. On projects like our 415kW rooftop at DB Santasalo in Bulli, getting the roof right up front is what keeps the array performing quietly for years.

Structural capacity: can it carry the load

The first question is whether your roof structure can safely take the added weight of the array, mounting system and the wind and uplift forces that come with it. This depends on your building's design, age and materials.

For larger commercial installs we'll often involve a structural engineer to confirm the roof can handle the load without reinforcement. If it needs strengthening, it's far better to know that before install day than after.

• Roof framing type, spans and spacing
• Existing loads already on the roof (plant, HVAC, ducting)
• Wind region and uplift requirements for your location
• Whether an engineer's sign-off is needed for your setup

Roof condition and remaining life

There's little sense mounting a system designed to run for decades on sheeting that's near the end of its life. We check the condition of the roof surface, fixings and flashings so panels don't outlast the roof underneath them.

If your roof is due for replacement soon, it's often smarter to sort that first. Doing both together can save the cost and disruption of pulling an array off and refitting it down the track.

• Corrosion, rust or degradation on metal sheeting
• Condition of existing fasteners and seals
• Age of the roof versus expected system life
• Any current leaks or water pooling

Orientation, pitch and shading

How much your system generates comes down to where the panels face, the roof angle and what casts shade across the day. North-facing areas typically do well, but east and west sections can suit a business that uses power across the morning and afternoon.

We map out shading from parapets, adjacent buildings, trees and rooftop plant so the array is laid out where it'll actually earn its keep. On a mixed roof, that often means combining several orientations rather than chasing one perfect aspect.

• Available roof area free of obstructions
• Orientation matched to when your site draws power
• Shading through the day and across seasons
• Room to expand later if your load grows

Access, penetrations and waterproofing

Every mounting point is a potential entry for water if it's not done properly. We plan penetrations carefully and detail how each one is sealed and flashed to keep your roof watertight, which matters a great deal for warranty and peace of mind.

Because we use our own team rather than subcontractors, the crew installing the mounts is the crew accountable for the waterproofing. We also check safe access, cable runs and where inverters and any battery gear will sit.

• Mounting method suited to your roof type
• Proper flashing and sealing at every penetration
• Safe access for install and future maintenance
• Practical routing for cabling and equipment

What happens after the check

Once we've been through the roof, we can give you a straight answer on whether it's ready, what work it might need first, and how a system could be laid out to suit how your business uses power. That's also where AI-driven energy arbitrage comes in, storing power when it's cheap and using or exporting it when prices climb.

Every roof and tariff is different, so the real numbers come from a proper site review rather than a rule of thumb. If you'd like us to take a look at yours, we're happy to come out and give you an honest read on what's possible.

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