Solar Panel Installation Step by Step | UK Guide 2026

1. Survey the property and roof

The first technical step should be a property survey, not simply selecting a package by panel count.

The installer should assess roof orientation, pitch, usable area, shading, chimneys, rooflights and access. They should also check whether the roof covering and structure appear suitable.

If your roof is damaged or approaching the end of its useful life, repairing it before the solar installation can avoid the cost of removing panels later. Homeowners who already know roof work is needed can compare the scope of that work through Get Free Quote’s roofing quote service.

Inside the property, the survey should consider the consumer unit, meter position, earthing arrangements and a practical route for cables between the roof, inverter and electrical supply.

Energy use matters too. A sensible design considers roof space, expected generation, daytime electricity demand and whether you may later add battery storage or an EV charger.

2. Design the solar PV system

After the survey, the installer specifies the number and model of panels, total array capacity in kilowatt-peak (kWp), inverter type, panel layout and estimated annual generation.

A south-facing roof normally maximises annual production. However, east- and west-facing roofs can still generate useful amounts of electricity. Energy Saving Trust estimates that east- or west-facing systems tend to generate around 15–20% less electricity than an equivalent directly south-facing system.

Shading from trees, chimneys and nearby buildings should also be assessed. In some situations, optimisers or microinverters can reduce the effect of partial shading.

If a battery is included, check its usable capacity, power rating, warranty and operating mode. Also check whether backup during a power cut is actually included. A standard solar-and-battery installation does not automatically keep the house powered when the grid fails.

3. Confirm planning, Building Regulations and grid requirements

Many domestic rooftop systems do not need a full planning application, but rules vary across the UK and depend on the property.

In England, rooftop solar can often qualify as permitted development subject to conditions. For example, permitted-development rules restrict how far equipment can project beyond the roof plane and generally prevent panels from extending above the highest part of the roof. Listed buildings and some properties in designated areas require additional consideration. Check the current GOV.UK permitted-development guidance or your local planning authority before proceeding.

The installer should also explain who is responsible for Building Regulations compliance and the grid connection.

Energy Networks Association now operates ENA Connect Direct for domestic low-carbon technology connection applications. Smaller generation installations may follow the G98 route, while larger or more complex systems can require G99 approval. The applicable process should be established during design rather than after the installation.

4. Erect scaffolding and install the roof mounting system

For a typical pitched-roof installation, scaffolding normally goes up before solar work starts. It provides safe roof access and a working platform for moving equipment.

Installers then attach the mounting system to the roof structure.

On many tiled roofs, selected tiles are lifted so roof hooks or brackets can be secured to rafters or another suitable structural point. Tiles are replaced around the brackets and the installation must remain weatherproof.

Metal mounting rails are then fixed to the brackets and aligned. These rails form the frame that supports the solar modules.

Slate, standing-seam metal and flat roofs need different mounting arrangements. The system should therefore suit the actual roof rather than use a generic fixing method.

5. Fit and wire the solar panels

Once the mounting rails are ready, installers lift the panels to roof level and clamp them securely into place.

The panels are then electrically connected on the DC side.

With a conventional string inverter, several panels are usually connected together into one or more strings. Those strings feed the inverter. With microinverters, DC-to-AC conversion takes place at or close to individual panels.

Cables should be securely supported and protected from abrasion. Connectors must be compatible and correctly assembled because poor DC connections can create electrical faults and overheating.

The completed array should follow the agreed design unless a site condition requires a properly considered change.

6. Install the inverter and optional battery

Solar panels generate direct current, or DC. Household appliances use alternating current, or AC.

The inverter performs that conversion.

Depending on the equipment and property, the inverter may be installed in a garage, utility area, loft or another appropriate position. Manufacturer requirements, temperature, cable lengths and maintenance access all influence the final location.

If battery storage forms part of the project, installers will also fit the battery and relevant control equipment. They should explain when the battery charges, when it discharges and how it interacts with solar generation and your electricity tariff.

Monitoring equipment, export limitation and solar-aware EV charging controls may also be fitted at this point.

7. Connect the solar system to the consumer unit

A suitably qualified electrician connects the inverter’s AC output to the household electrical installation using the required protective devices, isolators and cables.

The exact arrangement varies between homes.

Older or unsuitable electrical equipment may need additional work before the solar installation can be connected safely. This is one reason quotations should clearly distinguish the standard installation from possible consumer-unit or cabling upgrades.

Electricity may need to be switched off briefly while the final connection is completed.

Once operational, solar generation can supply electricity being used in the home. Surplus electricity can then be stored, diverted to another load or exported to the grid, depending on the system design.

8. Test and commission the system

Panels being physically attached to the roof does not mean the installation is complete.

The installer should test the DC and AC sides of the system, check protection and inverter operation and confirm that monitoring works correctly.

You should be shown how to recognise normal operation, view generation data and isolate the system if necessary.

Ask what normal performance should look like and who to contact if the inverter displays a warning or stops producing electricity.

A functioning monitoring app is useful, but it is not a substitute for proper electrical testing and commissioning.

9. Complete registration, handover and export setup

After commissioning, the installer should complete the applicable network paperwork and provide the documents relevant to your installation.

Keep your installation certificate where applicable, equipment details, warranties, estimated performance information and operating and maintenance instructions with your property records. Energy Saving Trust also advises that installers explain maintenance checks and important inverter fault signals.

If you want to receive payment for eligible surplus electricity in Great Britain, you can apply for a Smart Export Guarantee tariff through Ofgem’s listed suppliers.

Ofgem confirms that qualifying SEG licensees pay eligible generators for exported renewable electricity. Your export supplier does not have to be the same company that supplies your household electricity.

How long does solar panel installation take?

A straightforward domestic installation commonly takes one to two days on site, according to Energy Saving Trust. Scaffolding may be erected earlier and removed later.

The full project takes longer because survey, design, equipment scheduling, DNO requirements, installation and certification are separate stages.

Battery installation, electrical upgrades, difficult roof access or grid constraints can extend the programme.

When comparing quotes, ask for two timescales: the expected time on site and the expected period from signing the contract to completed handover.

How much does solar panel installation cost?

Energy Saving Trust currently gives around £7,600 as the typical cost of a home solar panel system. Actual prices vary with system size, roof access, scaffolding, equipment, electrical work and battery storage.

Treat national averages as guides rather than quotations.

A useful quote should identify the proposed system size, estimated annual generation, exact equipment, scaffolding and access costs, electrical work, certification, warranties and exclusions.

What should you check before signing off the installation?

Before the team leaves, confirm that the system is generating, monitoring works, labels and isolators are in place and you understand the shutdown procedure.

You should also confirm who handles the DNO paperwork, when outstanding certificates will arrive, what each warranty covers and how aftercare works.

It is sensible to photograph the completed array, inverter, meters, battery if fitted and any changes to your consumer unit.