How to install solar panels on a UK home

Video by Project Solar UK. This walk-through is based on the video “Installing Solar Panels on a UK roof – Full Walkthrough” from Project Solar UK, one of the country’s most established solar installation companies with over 45,000 systems fitted. Their channel is worth bookmarking if you want honest, practical content about solar for UK homes rather than the usual sales fluff.

1. Assess your roof

South-facing roofs at a pitch of 30–40 degrees give the best output in the UK, but east- or west-facing roofs still generate useful amounts — typically 80–85% of the south-facing equivalent. North-facing roofs are generally not worth it unless there is no other option.

The roof structure needs to be sound. Installers will check the felt, battens, and tiles before committing. If the roof needs reroofing within five years, do that first — you do not want to pay to remove panels and put them back again.

2. Size your system

A standard UK domestic system is 3.5–6kW peak output, using 8–16 panels. Bigger is not always better: if you export most of what you generate (because you are out all day), you will earn relatively little from the SEG. Size the system to match your daytime consumption if possible.

Adding a battery storage system is increasingly popular and allows you to use more of what you generate in the evening. It adds £2,000–5,000 to the cost but significantly improves self-consumption. Worth modelling with your installer.

3. Get at least three quotes from MCS-certified installers

MCS (Microgeneration Certification Scheme) accreditation is not optional — it is required to claim the Smart Export Guarantee and any future government incentives. Check the MCS installer database before you take any quote seriously. Anyone offering to do it cheaper without MCS certification is not worth the risk.

Watch out for salespeople who push you to sign on the day. A good installer will give you a quote, leave you to think about it, and answer follow-up questions without any pressure. If they are rushing you, move on.

4. Check whether you need DNO approval

Systems over 3.68kW per phase (which covers most single-phase domestic properties) need approval from your Distribution Network Operator before the installation. Your installer will handle the G99 application, but it can take several weeks. Factor this in when planning your timeline.

Smaller systems under 3.68kW use a simpler G98 notification, which is just an information-only process and does not require waiting for approval.

5. Installation day: the roof work

A typical domestic install takes one day for a team of two. The roof work comes first: fixing the mounting rails to the rafters with flashing kits around the fixings to keep the roof watertight, then clipping the panels to the rails. Modern mounting systems are fast and tidy when done properly.

DC cables run from the panels down to the inverter location — usually inside the loft, garage, or utility room. These carry high-voltage DC current and must be protected from damage and heat. A good installer will secure them properly, not just leave them draped under the tiles.

6. The inverter and consumer unit connection

The inverter converts DC from the panels into 230V AC for your home. String inverters (one box for all panels) are the most common and straightforward. Microinverters (one per panel) are slightly more expensive but handle partial shading better and make individual panel monitoring easier.

Connecting to the consumer unit must be done by a Part P-registered electrician. Most solar installers cover this as part of the installation, but confirm it upfront. The connection includes a generation meter so you can see exactly what you are producing.

7. Commission and test

Once everything is connected, the installer will commission the system: checking open-circuit voltages, string currents, and inverter operation. They should show you the monitoring app and explain what normal generation looks like at different times of year — so you know if something drops off in future.

You will get a commissioning certificate and MCS certificate. Keep these safe. They may be needed when you sell the property or make an insurance claim.

8. Register for the Smart Export Guarantee

Once the system is commissioned and MCS-certified, register with an SEG licensee to get paid for the electricity you export. Rates vary — currently 4–15p per unit depending on the supplier — so it is worth comparing before committing to one.

Some suppliers offer smart export tariffs that pay more during peak demand times, which can boost the return further if you are flexible about when you draw from the grid.

When to call a handyman

The panel installation, inverter wiring, and consumer unit connection are all work for certified professionals. That said, there is often peripheral work a handyman can help with: making good around cable entry points, tidying up the loft after cabling, fitting battery storage shelving, or dealing with any minor roof tile repairs identified during the survey. Give Richard a call for that side of things.