Our guide to solar panel installation

Solar PV panels work by using the sun's energy to generate electricity. The electrons in your solar PV panels are activated by sunlight, generating an electric current. The energy flow then passes through an inverter to power your home or office. 

The two most commonly used solar panel types are:  

• Monocrystalline panels: Created from a single piece of silicon, these are the most expensive solar PV panels and the most efficient.  

• Polycrystalline panels: These panels are cheaper because they use multiple pieces of silicon. They’re also less efficient, and you’ll need more panels to generate the same amount of electricity. 

But how much does solar panel installation cost? You can expect to pay, on average, between £150 and £300 for a single PV panel. On average, installation costs add an extra 55% to your quote. For instance, a ten-panel system will cost £9,000 to £10,000 fully installed.  

Over one million homes in the UK generate electricity with solar PV panels. Moreover, new planning rules are set to make installation even more accessible. If you’re thinking about domestic solar panel installation, here’s what you need to consider: 

• What size solar panel system will I require? Figure out your electricity use before you buy your panels. For instance, a 4kW system comprising ten panels will power the average three-bedroom house. 

• Is your roof suitable? Your roof should ideally be south-facing, unshaded between 10-4 and angled between 10 and 60 degrees for best performance.

• Is your roof structurally sound? Ten solar panels weigh around 200kg, so your roof may require a structural inspection. 

• Do you need a solar battery? A solar battery lets you store aunty energy you don’t use, but can add £4,500 to your installation costs. Otherwise, you can sell your unused power back to the grid via the SEG. 

• Will you need planning permission? Solar panel installation falls under permitted development unless your home is listed or in a conservation area. 

• How long does solar panel installation take? A straightforward install can take a day. Nonetheless, complex installations or remedial work will take additional time and add to your costs.

Businesses stand to save thousands on their energy bills by investing in solar panels. New government rules will eliminate planning red tape, making commercial solar panel installation straightforward. 

A commercial 10kW system costs £9,500, plus £2,000 installation. Moreover, maintenance costs are extremely low, with professional servicing required every 4-6 years.  

Businesses and households can benefit from the Smart Energy Guarantee, which pays you to export energy back to the grid. You could also benefit from interest-free funding to invest in energy-efficient technologies. Tax relief and zero-VAT are added sweeteners for adopting a commercial solar PV system. 

Are you thinking of solar panel installation but not sure what’s involved? Once you’ve compared quotes from trusted installers, here’s what to expect:

• Putting up scaffolding: If you live in a two-storey home, scaffolding is a requirement for roof work.

• Fitting frames and hooks: Next, your installer fits a system of hooks and rails to your roof timbers. This frame holds your solar panels in place.

• Attaching the solar PV panels: Your solar panels are ready to be clipped into the frame and wired up to the inverter.

• Connection to inverter and grid: The inverter converts DC input from your solar panels to AC current suitable for your home and the national grid. Your system will also be fitted with an Ofgem-approved generation meter. You can expect your electricity to be switched off briefly while this is carried out.

• System checks and documentation: Finally, your installer will conduct safety checks and power up the system. When they’re satisfied everything works correctly, they’ll hand over all relevant documentation, including warranties and manuals.

Planning permission is often unnecessary as solar panels fall under permitted development. It’s worth remembering, however, that your solar panels installation must meet building regulations. Additionally, your PV installation needs to satisfy the following conditions:

• The effect on the appearance of the building should be minimal.

• Any unused equipment must be removed as quickly as possible.

• The system must not exceed the highest part of the roof.

• The system mustn’t protrude more than 0.2m beyond the roof slope.

There are occasions when planning permission is required. You’ll need to visit the Planning Portal if:

• You have a flat roof

• You live in a listed building

• You live in a conservation area

You might be surprised to know that you can install solar PV panels on a listed building. You’ll need to apply for the following permissions:

• Listed Building Consent: any unauthorised work is a criminal offence and can result in prosecution. You’ll need LBC before applying for planning permission.

• Planning permission: Apply for planning permission online through the Planning Portal.

Bear in mind that, to qualify for LBC, you’ll need to show that your installation is completely reversible and won't alter the structure in any way.

The most significant chunk of solar PV panel installation costs is labour. Depending on where you live, expect to pay £300 to £500 per day. 

A typical solar installation requires two professionals, so your final fees will be £600 to £1,000 per day. Expect to pay for two or three day’s labour costs for larger and more complex installations. 

These are the estimated costs for your home, depending on size: 

• 3kW system (1-2 bed house) = £7,000-£8,000 

• 4kW system (2-3 bed house) = £9,000-£10,000 

• 5kW system (3-4 bed house) = £11,000-£12,000 

• 6kW system (4-5 bed house) = £12,000-£13,000

Take a look at our guide to solar panel prices for more information on estimated costs. 

So, how long does solar panel installation take? For a small-scale domestic installation, one or two panels can be installed in a matter of hours.  

Generally, you can expect a high-quality 4kW system to be installed in two days. Larger systems or complex installations, e.g. flat roofs, will take longer. 

For large-scale commercial solar installation, allow a 4-12 week timescale for project delivery.

Investing in solar panel installation is a big decision. Naturally, you want the best people for the job. But how do you ensure your solar panel installers are the real deal?

Look for accreditation 

Your solar panel installers must be MCS accredited to qualify for SEG payments. Additionally, look for accreditations from the Solar Trade Association (STA), Renewable Energy Assurance Limited (REAL), or the Renewable Energy Consumer Code (RECC).  

Do your due diligence 

Would you buy a washing machine without researching customer reviews? The same applies to solar panel installation. Look for companies that have operated for several years and are happy to share customer testimonials and references. 

Don’t be pressured 

Good companies don't need to rely on high-pressure sales tactics to make a sale. Instead, they'll offer advice and recommendations to improve your home's energy rating. Be wary of over-the-phone quotes. A credible installer will require a home visit to inspect your roof structure before giving you a quote. 

Clarify your quote 

Any quotes should be written down and clearly itemised. Don’t settle for a figure plucked out of the air. Good solar panel installers will be transparent about what’s included, so you don’t get any nasty surprises. 

Check after-sales care 

Look for extended warranties and guarantees on your solar PV panels and installation. A trusted company will be happy to offer cover for labour costs as a sign of their confidence in their products and services. 

Solar installation is a significant home improvement, so don’t choose a solar panel installer on a whim. Trust your quote comparison to SpotDif. 

We only work with trusted solar panel suppliers and installers in your area—the kinds of businesses that rely on word of mouth and their good reputation. As a result, you’ll get great solar panel installation quotes on your doorstep. And because we take the time and effort out of unearthing the best quotes, you can compare at your leisure to make an informed decision. 

Ready to switch to solar power and slash your energy bills? Let SpotDif find you the best quotes on solar panel installation near you.