How Re-Roofing Works When Solar Panels Are Already Installed

Not every property gets the sequencing right the first time. If you already have solar panels installed and your roof is now due for replacement - whether due to age, storm damage, corrosion, or an underlying asbestos issue - you're not stuck.

Re-roofing around an existing solar array is a routine job for an experienced roofing contractor, but it does involve extra steps, extra coordination, and a few cost considerations that a standard re-roof doesn't.

Here's what actually happens when a roof with solar needs to be replaced.

Step 1: Roof and Solar Assessment

Before any work begins, the roofing contractor needs to assess two things: the condition of the roof itself, and the layout, mounting method and condition of the existing solar array. This determines:

• Whether the full roof needs replacing, or only sections

• How the panels are currently mounted (roof-penetrating brackets vs. standing seam clamp-fix systems)

• Whether the existing mounting rails and brackets can be reused or need replacing

• Whether the inverter, wiring and isolators will need to be temporarily disconnected

For larger commercial or warehouse arrays, this assessment stage is more involved, since panel counts are higher and disconnection needs to be coordinated with a licensed electrician.

Step 2: Engaging a Licensed Solar Electrician

Solar panels are connected to the property's electrical system and, in many cases, the grid. Removing and reinstalling an array isn't just a physical roofing task - it requires a licensed electrician (usually the original installer, or another accredited solar provider) to safely isolate, disconnect and later reconnect and re-certify the system. A reputable roofing contractor will coordinate this rather than attempting to move panels without qualified electrical sign-off.

Step 3: Panel Removal

Once the system is isolated, the panels are carefully removed and stored on-site (or off-site for larger arrays) for the duration of the roofing work. At this stage:

• Panels are individually labelled or mapped to their original position, particularly for larger arrays, to simplify reinstallation

• Mounting rails and brackets are removed along with the panels where they need to be replaced as part of the new roof

• Any roof penetrations from the original mounting system are noted, since these need to be properly resealed or reworked into the new roofing

Step 4: Re-Roofing

With the panels and mounting hardware out of the way, the re-roof proceeds largely as a standard project - old sheeting is stripped back, the structure is inspected and repaired if needed, insulation is replaced or upgraded, and new sheeting is installed. This is also the ideal time to address anything the solar array may have been masking, such as corrosion or damaged fasteners underneath the old mounting points, and to improve insulation for better energy-efficient roofing performance while the roof is already exposed.

If the original roof contains asbestos, this stage also needs to follow the correct removal and disposal process - see our guides to commercial asbestos roof removal and residential asbestos roof replacement for what that involves.

Step 5: Reinstalling the Solar Array

Once the new roof is complete, mounting brackets are refitted - either the original hardware if it's still in good condition, or new brackets suited to the new roof profile. Panels are then reinstalled in their original layout and reconnected by the licensed electrician, who will also test the system and confirm it's performing correctly before final sign-off.

Where possible, it's worth using this step to switch to a clamp-fix mounting system if the new roof profile allows for it, since this avoids the roof penetrations required by older bracket-and-screw mounting methods - reducing the risk of leaks over the life of the new roof.

What This Costs Compared to a Standard Re-Roof

Re-roofing around an existing solar array typically costs more than a standard re-roof, mainly due to:

• Electrician fees for disconnection, isolation and reconnection

• Labour for the additional panel removal and reinstallation steps

• Potential replacement of mounting rails or brackets that aren't compatible with the new roof

• Extended project timelines, since roofing and electrical trades need to be scheduled around each other

This is exactly why re-roofing before solar installation is the more cost-effective sequence where it's an option - but for properties that already have solar installed and a roof that genuinely needs replacing, there's no way around it, and the cost is generally well justified against the alternative of a failing roof underneath a working solar system.

Minimising Disruption

For commercial and warehouse properties in particular, downtime and disruption matter as much as cost. An experienced contractor will plan the project in stages - working across sections of a large roof rather than removing an entire array at once - to keep as much of the solar system generating as possible throughout the project, and to minimise disruption to operations underneath. This is the same project-management approach we bring to commercial re-roofing generally, where minimising disruption to an operating building is often as important as the roofing work itself.

Choosing a Contractor for This Type of Job

Not every roofing contractor is comfortable coordinating around an existing solar installation, so it's worth asking directly about their experience with solar removal and reinstallation projects before engaging them. A contractor who can manage both the roofing and the electrical coordination - rather than leaving you to organise a separate solar company - will generally deliver a smoother, better-sequenced project.

VIC Metal Roofing has experience re-roofing residential, commercial and industrial properties with solar already installed, coordinating panel removal and reinstallation alongside the roofing work from start to finish. Get in touch with our team for an assessment if your roof needs replacing and you already have solar on site.