DIY Solar Panels UK: Can You Install Them Yourself?

DIY costs (panels and equipment only): - 10 × 400W panels: £1,500–£2,500 - String inverter: £500–£1,000 - Mounting kit and fixings: £300–£600 - DC and AC cabling: £100–£200 - MC4 connectors and isolators: £50–£100 - Electrician for Part P sign-off: £300–£500 - Total DIY: £2,750–£4,900

Professional installation (all-in): - £5,000–£8,000 for a 4kW system - Includes: panels, inverter, mounting, wiring, DNO notification, MCS certification, warranty, scaffolding

The real cost comparison: - DIY saves £2,000–£3,000 upfront - But loses £200–£500/year in SEG payments over 25 years = £5,000–£12,500 lost income - Plus risk of voided warranty on a £5,000+ system - Plus potential insurance issues

Net result: DIY costs MORE over the system lifetime.

Source: MCS installer pricing 2026; Ofgem SEG rate data.

There are a few narrow scenarios where DIY solar can work:

Off-grid systems (sheds, caravans, boats): - Small systems (100W–1kW) not connected to the grid - No MCS certification needed (no grid connection = no SEG anyway) - Low voltage DC systems can be safer to work with - Portable panels for camping or motorhomes

Ground-mounted garden systems: - No roof work = lower fall risk - Can be a learning project if kept small - Still needs Part P electrician for grid connection

Expansion of an existing MCS-certified system: - Adding panels to an existing mounting system - Must still have the electrical work checked by a qualified person - May void existing warranty — check first

For a primary residential grid-tied system, professional installation is almost always the better financial decision.

If you do choose to install solar panels yourself, you must comply with:

1. Building Regulations Part P — all electrical work connecting to the mains must be certified by a Part P registered electrician, or you must notify your local building control before starting work 2. Planning permission — most residential solar does not need planning permission under permitted development rights, but conservation areas and listed buildings have restrictions 3. G98/G99 notification — your DNO must be notified before any generation equipment is connected to the grid. Systems under 3.68 kW (single phase) follow the simpler G98 process. Larger systems require G99 application and approval. 4. IET Wiring Regulations (BS 7671) — all electrical installation work must comply with current wiring regulations 5. Structural assessment — you must ensure your roof can support the additional weight (approximately 20kg per panel)

Failure to comply with Part P can result in enforcement action from your local authority, and may cause problems when selling your home.

Source: UK Government Building Regulations Part P; ENA G98/G99 guidelines.

Use a professional MCS-certified installer. The upfront saving from DIY (£2,000–£3,000) is wiped out by lost SEG income (£5,000–£12,500 over 25 years), warranty risk, and safety concerns.

Get 3 quotes from MCS-certified installers, compare prices, and negotiate. The market is competitive — you may be surprised how close professional pricing is to DIY costs once you factor in everything.