The solar panel installation process What happens on installation day

How long it takes to get solar panels installed

Here's how the process runs, stage by stage, and how long each part usually takes. The day on your roof is only a small part of it. The Energy Saving Trust says an installer should take one to two days to fit solar panels, and longer for a more complex system.

For systems that don't need network approval, the whole thing usually takes two to three weeks. Timings vary depending on the size of the system, kit availability and the paperwork: larger systems wait for the network operator's approval, which can take up to 90 days, and homes that need planning permission or listed building consent take longer too.

How solar panels are attached to the roof

On-roof panels sit on aluminium rails, a few centimetres above your tiles, so they keep a low profile. The rails are held by brackets fixed to the roof timbers underneath. Together, the roof hooks, rails and clamps make up the mounting system.

1. Tiles come up. Our roofer lifts a tile or slate at each fixing point.
2. Brackets go on the rafters. Each roof hook is screwed into a rafter, not the tiles or battens, so the roof timbers support the weight. Then the tile goes back over it, trimmed if needed so it sits flat and keeps the roof watertight.
3. Rails go on the brackets. The rails mount across the roof, held secure by the hooks, and set the line for the panels.
4. Panels clamp to the rails. Clamps grip each panel's metal frame at the edges. Nothing is drilled through the panels themselves.
5. Cables run neatly to the inverter. From the solar array through the roof space to the inverter, usually in the loft or near your fuse board.

Under planning rules for houses, panels on a pitched roof can stand no more than 0.2 m proud of the roof slope and can't go above the ridge. MCS rules also keep them back from the roof edges unless extra measures are taken, which is why you'll see a margin around the panels. Where the mounting system isn't MCS 012 certified, MCS rules from 18 June 2026 ask for evidence of structural and wind loading calculations, fire performance and weather-tightness.

Flat roofs

On a flat roof, panels usually sit on frames that tilt them towards the sun instead of rails on a slope, and the planning limits are different. Our guide to solar panels on a flat roof covers both.

After installation

Your solar panel system starts to generate electricity as soon as it's switched on. Once installation is complete, there's paperwork, and we handle it:

• Network operator. Most home systems are "fit and notify": under MCS rules, installers must tell your electricity network operator within 28 days of switching on. We do it within 7 working days. Larger systems, over 3.68 kW, are approved before installation.
• MCS certificate. Normally issued within 10 days of commissioning. It shows your system was designed, installed and commissioned to MCS standards, and you need it to be paid for the electricity you export, so keep it safe.
• Electrical safety certificate. Adding a solar circuit is notifiable electrical work. We register it, and you receive a Building Regulations compliance certificate within 30 days.
• Your handover pack. We email it within 7 working days, with your warranties and system details. Certificates issued after that follow by email.
• Export payments. We explain how to apply for a Smart Export Guarantee tariff once your MCS certificate arrives.

The scaffolding comes down once the job's signed off.