Solar Installation Process: From First Survey to Switch-On

Installing solar panels is not a single job but a sequence: a survey, a design, paperwork, a day or two on the roof, an inspection, and a final permission before the system is switched on. Knowing the sequence in advance helps you judge whether an installer is organised, spot a step that has been skipped, and plan around the disruption. This guide walks through each stage.

Survey and design

Everything starts with a survey of your home. The installer, or a surveyor they send, measures the roof, notes its direction and pitch, checks the roof's condition and material, looks for shade, and inspects the electrical panel and the route cables will take. They will also ask for a year of electricity bills, so the design is based on real use rather than a guess.

From the survey comes the design: how many panels, of what wattage, in which layout, with which inverter, and whether a battery is included. A good design document shows the expected yearly production and the assumptions behind it — direction, tilt, shading and local sunshine — so you can follow the reasoning. If the design arrives without those numbers, ask for them before agreeing to anything.

Permits, approvals and paperwork

Before work starts, the installer usually handles the paperwork: a building or planning permit where one is required, and an application to the electricity utility for a grid connection. Some areas need no permit for a standard rooftop system; others do, and the rules vary by place. The installer should tell you which permissions apply to your address and who is responsible for each one.

This stage is often the slowest part of the whole process, and its length is mostly outside the installer's control — utilities and planning offices work to their own timetables. A realistic installer will give you a range, not a promise, and will keep you informed while approvals are pending. Do not let anyone start installing before the required approvals are in place.

Installation day

The physical installation usually takes one to three days for a typical home system, depending on its size and the roof. The crew first fixes the mounting rails to the roof, taking care to seal every fixing against rain. Panels are then lifted up, bolted to the rails and wired together. The inverter is mounted, usually near the electrical panel, and connected to the home's wiring, and the monitoring system is set up.

Expect noise, scaffolding and a crew on the roof, and a brief power interruption while the electrical work is connected. A good crew leaves the roof and the garden tidy, shows you the inverter and the monitoring app, and explains the basic checks — what the display means, what to do if it shows a fault, and who to call. Ask for that walkthrough before they leave, and for the manuals and warranty documents in one place.

Inspection and permission to operate

After installation, the system is inspected — by the local authority where required, and by the utility before it is connected to the grid. The inspection checks that the mounting, wiring and safety equipment meet the rules, and that the system shuts down correctly when the grid is off. Only after inspection and the utility's permission to operate, often shortened to PTO, should the system be switched on for normal use.

The gap between installation and permission can be days or weeks, and the system produces nothing in the meantime. That is normal, not a fault, though it is worth knowing in advance so the wait does not feel like a problem. Once permission arrives and the system is switched on, check the monitoring app over the first few days: production should follow the weather in a sensible pattern, and anything flat or zero on a sunny day is worth a call to the installer.