Solar panel installation UK.
What actually happens, what it costs, and how to find a good installer.
A straight-talking guide to the solar panel installation process in the UK. The process from survey to switch-on, what the installation costs in 2026, how to check if your roof works, what MCS accreditation actually means, and the red flags that tell you to walk away from a quote.
A standard residential solar panel installation takes one to two days on the roof, but the full process from quote to switch-on is usually four to eight weeks, most of which is waiting for DNO grid connection approval. The installation itself is not complicated. Finding a genuinely good installer is the harder part. Only use MCS-accredited installers or you lose access to the Smart Export Guarantee and most government schemes. Everything else on this page tells you what to expect and what to watch out for.
How solar panel installation works in the UK: the full process step by step
Most people are surprised by how hands-off the process is once you have chosen your installer. You make two decisions: which quote to accept and when the installation can happen. The installer handles everything else. Here is what actually happens at each stage.
Survey and site assessment
Before quoting, a good installer visits your property to assess your roof. They check the orientation, pitch, shading, structural condition, and your existing electrical setup. They look at your electricity bills to size the system properly and discuss whether battery storage makes sense for your usage pattern. This should be free. If an installer quotes without visiting your property, that is a red flag.
1 to 2 hours at your propertyQuote, system design, and deposit
Your installer provides a written fixed-price quote detailing the system size, number of panels, panel brand, inverter type, battery if included, and the expected annual generation in kWh. A payback period calculation should be included. Once you accept, you pay a deposit, typically 10 to 25% of the total cost. The installer then orders your equipment and begins the administrative process.
Quote received within a few days of surveyDNO notification or application
Before installation, your installer must notify or get approval from your Distribution Network Operator, the company that manages the electricity grid in your area. Systems up to 3.68kW per phase are typically notified rather than approved, which is quick. Larger systems require a formal G99 application that can take two to six weeks depending on your DNO. This is usually the longest part of the process and the part most people are not expecting. Your installer handles it, but it is worth knowing it exists so the wait does not catch you off guard.
Typically 2 to 6 weeks for DNO approvalScaffolding
Solar panel scaffolding goes up one to two days before installation. For a standard two-storey home this typically costs £300 to £600 and should be included in your quote. The scaffold stays up for a few days after installation until your installer has signed off the work and removed equipment. Check your quote explicitly confirms scaffolding is included because some installers quote it separately.
Erected 1 to 2 days before installationThe installation day
A team of two to four engineers installs the mounting brackets, attaches the panels, runs the DC cabling through the roof and loft to the inverter location, installs the inverter, connects to your consumer unit, and fits the generation meter. For a standard 4kW system this takes one day. A larger system with a battery takes two days. You will be without electricity for a few hours while the consumer unit work is done. You need to be home, or at least a keyholder needs to be.
1 to 2 days on siteCommissioning and handover
Once installed, the system is commissioned and tested. Your installer shows you how to read the inverter display or app, what the numbers mean, and what to do if something looks wrong. They then register the installation with MCS, which generates your MCS certificate. Keep this document. You need it to register for the Smart Export Guarantee with your energy supplier. Most SEG applications are done online in under 30 minutes.
MCS certificate issued within a few daysWhat does solar panel installation cost in the UK?
Solar panel installation cost in the UK varies by system size, panel brand, inverter type, and whether you are adding battery storage. All prices below include labour, mounting equipment, inverter, generation meter, scaffolding, and 0% VAT. They are what you actually pay, not headline panel prices that exclude installation.
| System size | No. of panels | Installed cost | Annual generation | Approx payback |
|---|---|---|---|---|
| 3kW | 8 panels | £5,000 to £6,500 | 2,600 kWh/year | 9 to 12 years |
| 4kW | 10 panels | £6,000 to £8,000 | 3,400 kWh/year | 7 to 10 years |
| 5kW | 12 to 13 panels | £7,000 to £9,500 | 4,300 kWh/year | 7 to 10 years |
| 6kW | 14 to 16 panels | £8,000 to £11,000 | 5,100 kWh/year | 7 to 10 years |
| 4kW + battery | 10 panels + battery | £9,000 to £13,500 | 3,400 kWh + stored | 8 to 12 years |
These are honest mid-market ranges. You can find cheaper quotes but cheaper usually means lower quality panels, a less experienced installer, or hidden costs appearing later. You can find more expensive quotes from premium brands charging for the name rather than meaningfully better performance. The cost of installing solar panels has come down significantly over the past decade. A 4kW system that cost £12,000 in 2012 now costs £6,000 to £8,000 with better panels and longer warranties.
If you get a quote significantly below these ranges, find out specifically where the cost is being reduced. Common places: cheaper off-brand panels with shorter warranties, smaller installers who subcontract the actual work, no scaffolding included (added later), or a lower capacity system than what you discussed. None of these are automatically wrong, but they are worth understanding before you sign. A quote that is 25% below the range for no explained reason is worth questioning.
Is my roof suitable for solar panels?
Most UK roofs are suitable for solar. The key variables are direction, pitch, shading, and structural condition. Here is what each means for your system output.
South-facing
The optimal orientation for UK solar. A south-facing roof at 30 to 40 degrees pitch captures maximum solar radiation throughout the day. If you have a south-facing roof with no significant shading, solar is a strong investment.
South-east or south-west
Very close to south-facing performance. The small reduction in output rarely changes the financial case. Most south-east and south-west facing roofs make excellent solar installations.
East or west-facing
East-facing roofs generate more in the morning, west-facing more in the afternoon. Both can still make solar financially viable, particularly if you use electricity throughout the day. Your installer will model the output for your specific situation.
Flat roof
Flat roofs use angled mounting frames to tilt panels south at the optimal pitch. Works very well and is the standard for most commercial installations. For domestic properties, the mounting frames take up more roof area so you need enough flat space.
North-facing
A north-facing roof in the UK receives significantly less solar radiation than other orientations. The financial case rarely stacks up. If you only have north-facing roof space, discuss ground-mounted solar panel systems with your installer as an alternative.
Significant shading
Trees, chimneys, or neighbouring buildings shading your roof between 10am and 3pm significantly reduce output. A solar panel survey should include shading analysis. Micro-inverters or optimisers can mitigate partial shading but they cannot compensate for heavy shading entirely.
If you are wondering specifically how many solar panels can fit on your roof, a rough calculation is: usable south-facing roof area in square metres divided by 1.7 gives you the approximate number of standard 400W panels. A 25 square metre south-facing roof fits around 14 panels, giving you a 5.6kW system. Your installer will work this out precisely during the survey.
Find out if your roof works for solar
Get a free assessment from an MCS-accredited installer. They will tell you honestly whether solar makes sense at your property and give you a fixed-price quote with no obligation.
Get a free quoteHow to choose a solar panel installer: what actually matters
There are thousands of solar panel installers in the UK and the quality varies enormously. The solar industry had a period of sharp growth followed by a significant number of companies going under, leaving customers with voided warranties and no recourse. Here is how to tell a good installer from a bad one before you hand over any money.
Pressure to sign on the day of the survey visit. Any installer who offers a time-limited discount if you sign today is using a sales tactic that good companies do not need. Take the quote away, compare it, and make your decision without pressure.
They cannot confirm in writing whether scaffolding is included. Scaffolding is a meaningful cost and should be in the quote. Vague answers about what is included in the total price are a warning sign about how disputes will be handled later.
They guarantee specific savings figures without seeing your bills. Anyone promising you will save a specific amount per year before reviewing your actual electricity consumption and tariff is making numbers up. Projected savings are estimates that depend on your usage, feed-in tariff rate, and how much of your solar generation you consume directly.
A very large deposit is required upfront. A 10 to 25% deposit on signing is standard. A demand for 50% or more before installation is unusual. If they need that much cash up front, it raises questions about their working capital position.
They claim the installation does not need DNO approval when your system is over 3.68kW. Every grid-connected system above this threshold requires DNO notification at minimum. An installer claiming otherwise either does not understand their legal obligations or is planning to skip the process, which creates compliance problems for you.
MCS accreditation and DNO solar panels: what they mean and why they matter
What is MCS accreditation?
The Microgeneration Certification Scheme is the industry quality standard for small-scale renewable energy installations in the UK. MCS-accredited installers are trained, assessed, and regularly audited. The MCS certificate issued after your installation is the document you need to register for the Smart Export Guarantee and access government grant schemes. Without it, you cannot access these financial benefits regardless of how well the system performs.
What is DNO approval for solar panels?
Your DNO, Distribution Network Operator, manages the electricity distribution network in your area. Before your solar system can export to the grid, the DNO must be notified or give approval. Systems up to 3.68kW are notified under G98, which is fast. Systems above this need a G99 application, which involves the DNO assessing the impact on local grid infrastructure. DNO solar panel approval can take two to six weeks. Your installer handles all of this but it is the most common reason for installation delays.
Smart Export Guarantee
The Smart Export Guarantee requires energy suppliers to pay you for electricity your solar system exports to the grid. Rates vary from around 3p to 15p per kWh depending on your supplier. You register with your energy supplier after installation using your MCS certificate. Over the lifetime of a 4kW system this can add up to several thousand pounds. It takes around 30 minutes to register and is worth doing promptly after your installation is complete.
Solar panel installation regulations UK
Solar panel installation in the UK must comply with Part P of the Building Regulations (electrical safety), the relevant British Standards for solar PV systems, and DNO connection requirements. Your MCS-accredited installer is responsible for compliance with all of these. You should receive a building regulations compliance certificate after installation. If your installer does not mention this, ask for it.
Can I install solar panels myself?
For a grid-connected home solar system in the UK, doing the installation yourself is not practical for most people and not advisable for most of the rest. The electrical work must be done by a qualified electrician to comply with Part P of the Building Regulations. The DNO notification or approval process requires specific documentation. And without MCS accreditation the installation cannot be certified, which means no Smart Export Guarantee and no access to grant schemes.
DIY solar panel installation makes much more sense for off-grid applications: a system powering a shed, a garden office, a narrowboat, or a campervan. These do not connect to the grid, do not require DNO notification, and do not need MCS certification. A capable DIYer with basic electrical knowledge can install a small off-grid solar system safely and cost-effectively. There is an active community around this and plenty of good guidance available.
For a grid-connected home system, the financial benefit of professional installation, including access to SEG payments and the 0% VAT that applies to MCS-certified installations, almost always outweighs any saving from doing the installation yourself.
Questions people ask about solar panel installation
The physical installation takes one to two days. The full process from accepting a quote to your system being live is typically four to eight weeks, with most of the wait being DNO grid connection approval. Your installer handles the DNO process on your behalf but it can take two to six weeks depending on your network operator and system size.
Most UK roofs are suitable. South-facing at 30 to 40 degrees is ideal. East and west-facing lose around 15 to 20% output but still work well financially. North-facing is generally not worth it. Your installer will assess shading from trees and chimneys during a survey. The solar panel survey is free and tells you honestly whether solar makes sense at your specific property.
A rough guide: usable roof area in square metres divided by 1.7 gives you the approximate number of standard 400W panels. A 20 square metre south-facing roof fits around 11 panels, giving you a 4.4kW system. Most semi-detached and detached UK homes have enough roof space for a 3 to 6kW system. Your installer calculates this precisely during the survey.
DNO stands for Distribution Network Operator, the company managing the electricity grid in your area. Before your solar system can export to the grid, the DNO must be notified or give approval. Systems under 3.68kW are notified quickly under G98. Larger systems need a G99 application that can take two to six weeks. Your installer handles this on your behalf.
In most cases, no. Solar panel installation on domestic properties falls under permitted development in England, Wales, and Scotland provided the panels sit within the roof line and do not protrude more than 200mm. Listed buildings and conservation area properties may require planning permission. Your installer confirms the position for your property before work begins.
MCS, the Microgeneration Certification Scheme, is the quality standard for small-scale renewable energy installations in the UK. Only MCS-accredited installers can issue the certificate required to access the Smart Export Guarantee and most government grant schemes. Always verify an installer is MCS accredited before signing anything. You can check at the MCS website using their MCS number.
For a grid-connected home system, practically not. The electrical work requires a qualified electrician under Part P, DNO notification requires specific documentation, and without MCS certification you lose access to the Smart Export Guarantee and grant schemes. For off-grid systems on sheds, cabins, boats, or campervans, DIY is perfectly viable and there is a good community around it.
Related solar guides
Ready to get a quote from an MCS-accredited installer?
Free solar panel quote. Fixed price. No obligation. Usually usually within 1 business day.
Get my free solar quote