Solar Panel Roof Calculator
Estimate how many solar panels could fit on your roof — and the approximate system size in kilowatts — from your roof area.
Panels that could fit
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Approx. system size
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Results are estimates for planning purposes only. Every roof is different — for exact measurements and a fixed-price quote, book a free on-site inspection or call 0416 689 689.
How this solar calculator works
Not all of your roof can hold panels. Ridges, valleys, vents, skylights, shaded sections and poorly oriented faces all reduce the usable area — which is why this calculator asks for a usable portion rather than assuming the whole roof. Adjust it to suit your home: simple north-facing roof planes can use more of their area, complex or shaded roofs less.
Enter the physical size and rated output of the panels you're considering (both are on any panel datasheet) and you'll get a realistic upper estimate of panel count and system size. Don't know your roof area? Start with our roof area calculator.
Check your roof before you add solar
Solar panels typically stay on a roof for decades — far longer than a roof nearing the end of its life will last underneath them. Removing and reinstalling panels to fix or replace a roof later is a significant extra cost, so it pays to fix cracked tiles, rusted sheets, or tired bedding and pointing before the installers arrive. If you're planning solar, a pre-installation roof inspection is one of the cheapest insurance policies you can buy.
Ready To Protect Your Home?
Book Your Free Roof Inspection Today.
Whether you need emergency roofing, leak detection, storm damage repairs or simply peace of mind, our experienced roofing specialists are ready to help. No pressure. No hidden costs. Just honest roofing advice.