Is My Roof Suitable For Solar Panels?

If you’re asking, “Is my roof suitable for solar panels?” you’re taking an important step toward sustainability. Installing solar panels can help you generate your own electricity, reducing your reliance on the grid and lowering your energy bills. In some cases, solar panels can even earn you money by allowing you to sell excess power back to the grid.

All of this sounds amazing, but first, you need to know whether your roof is suitable for solar panels. Here, you can learn more about the necessary roof conditions and requirements for solar panels in our extensive guide.

For a quick estimation of your property, don’t forget to use our solar panel calculator tool for more information.

Is Your Roof Suitable for Solar Panels?

So, how do you determine if your roof is suitable for solar panels? There are three key factors to consider:

• ‍Legal (Planning Permission): While planning permission is rarely denied, it’s essential to check whether your home requires it before installation. Even if permission is initially refused, there are options to appeal or modify your plans.
• ‍Efficiency (Orientation, Size, and Angle): The efficiency of your solar panels depends on your roof’s orientation, size, and angle. These factors determine how much sunlight your panels will receive and, consequently, how much energy they can generate.
• ‍Structural (Weight-Bearing Capability and Obstructions): Your roof’s structural integrity is crucial. It must be able to support the weight of the solar panels, and any obstructions, like chimneys or vents, should be considered as they can impact panel placement and efficiency.

Efficiency and structural factors are key in determining whether solar panels will be cost-effective for your home. First, you’ll need to estimate how much energy your panels can generate. Then, consider any necessary modifications to your roof to accommodate the panels.

These are the primary factors to consider when evaluating your roof’s suitability for solar panels.

Legal factors

Before considering the efficiency and structural suitability of your solar panels, it's important to first check whether you're permitted to install them. For most people, this won’t be an issue—around 99% of homes don’t require special approval. Governments have continuously supported green energy initiatives, making the process relatively straightforward.

However, for the remaining 1%, certain restrictions may apply. You may need special permission if your property falls into one of these categories:

• It's a listed building
• It's located in a conservation area
• There are justified objections from a neighbour
• The panels pose a potential hazard, such as reflecting sunlight into drivers' eyes

While the first two situations are generally strict, the latter two might offer some flexibility to find a solution.

Neighbour Opposition to Solar Panels

First, (un)neighbourly opposition needs to be truly justified. It can’t simply be that the neighbour doesn’t like the look of solar panels. It’s your property, and these installations usually come under “permitted development”, which means you don’t even need to seek permission.

However, some objections are justified. Examples would include where angled panels (for example on a flat roof) cast significant shadows on their garden or living area. Similarly, causing excessive glare and reflection could be grounds for refusal. Generally, however, as panels sit flush with roofs and point skyward, these issues do not apply.

Potential Solar Panel Hazards

If you live near a busy road, there’s a small chance that your panels could reflect sunlight directly into motorists’ eyes at certain times of the day and year. If you think there’s a risk, it’s best to seek permission rather than being forced to take them down after accidents or complaints. Investigators can calculate precisely whether the risk would be significant with regard to the motion of the sun. If your plans are considered risky, it could be a case of adjusting the angle or situating the panels elsewhere.

Efficiency Factors

Solar panels perform best when they face the sun directly, ideally at a 90-degree angle. Anything less is considered less efficient, but that doesn't mean they won’t work.

In the UK, the sun rises in the east, moves over the south, and sets in the west, so your panels will never be at a perfect 90 degrees all day. Additionally, because the UK is far north of the equator, the sun only reaches about 60 degrees overhead in summer, and as low as 15 degrees in winter.

However, this is more about efficiency than functionality. Even if your panels are only operating at 50% of their maximum efficiency, they will still generate power, likely enough for your needs. And while direct sunlight is ideal, panels can still produce a significant amount of energy on cloudy days. In fact, clouds can scatter light, allowing more to reach the panels after the sun has passed directly overhead.

So, ask yourself these questions:

Which direction does my roof face?

Most houses have a standard gable (triangular) roof or a hip roof (where there’s no gable but the roof slopes towards the ridge). So unless you have a gable roof or live in a terraced house where the roofs face directly east and west, you’ve probably got at least one roof that’s facing towards the sun for a good part of the day.

Are east or west-facing roofs suitable?

East- or west-facing roofs will still harness light throughout the day, but a south-facing roof is always going to be better. An east-facing roof will gather more in the morning, while a west-facing roof will gather more in the afternoon. However, unless your ridge points precisely north-south, there will always be one side that’s a little bit better than the other.

What angle is the roof at?

Roof angle (pitch) ranges from very steep to flat. On houses with pitched roofs, the angle is normally in the 30–50° range. The angle combines with the direction to determine how well it will gather light if the panels are set flush to the roof. As it happens, these average roof angles are good for gathering light.

What about flat roofs? Well, clearly, solar panels mounted on a flat roof would be pointing directly up at the sky, so would never be firing on all cylinders in the UK. However, you can mount them at a tilted angle. Better still, that allows you to choose whatever angle is optimal, unlike with a pitched roof. Flat roofs are invisible to people at ground level, so there’s no aesthetic cost.

Is your roof big enough?

You could have a single panel on the only available section of roof, but in reality it might not be worth the effort. Much of the cost of solar panel installation is in connecting your setup to the grid and batteries, as well as potentially one-off items like scaffolding and installers’ labour.

Each extra panel does add to the cost, but the more panels you have, the better value your one-off expenses become. If you have money to burn and are committed to green energy, go for it! Otherwise, a small number of panels will take a lot longer to pay for themselves in energy savings.

Recommended Guide: How long do solar panels take to pay back for themselves?

Structural Factors

British houses are built with roofs designed to endure everything the weather throws at them—from scorching summer sun to gale-force winds, relentless rain, and even heavy snowfall. But when it comes to the roof requirements for solar panels, what do you need to consider?

The great news is that this inherent strength means most roofs are well-equipped to support solar panels. Each solar panel weighs around 18 kg, so even when factoring in a thick layer of snow, your roof should easily handle the load.

However, there are exceptions. Older roofs that are in need of repair might not be structurally sound enough to support solar panels without reinforcement. If you’re unsure about your roof’s condition, it’s wise to consult a structural engineer. A reputable solar panel installer should also assess whether your roof can bear the extra weight before proceeding with installation.

Certain roofing materials, like thatch, aren’t suitable for solar panels. However, most other types of roofs can accommodate panels without any issues.

Another structural consideration is the presence of a parapet on a flat roof or other parts of the building that might cast a shadow over the area where panels would be installed. While this doesn’t necessarily rule out the possibility of installation, it could significantly impact the efficiency of the panels.

House Suitability for Solar Panels

Beyond your roof’s suitability for solar panels, you must also consider the suitability of your house. Before installing solar panels, it’s essential to ensure your home meets certain criteria for a successful setup. Here is what you need to consider:

Planning Permission and Conservation Areas

Most homes in the UK can install solar panels without the need for planning permission, but if your property is a listed building or located in a conservation area, you may need to consult with your local council before proceeding. These areas often have restrictions to preserve the historical or aesthetic character of the buildings.

Grid Connection

The majority of UK homes have a single-phase connection, which can support a solar PV system of up to 4kWp—sufficient for most domestic setups. If you're considering a larger system, you'll need to get approval from your electricity provider to connect it to the grid.

Home Ownership

If you’re the homeowner, you’re free to install solar panels. However, if you live in a rented property, you will need your landlord’s permission. It's important to note that any financial incentives, such as Feed-in Tariffs (FiTs), typically go to the homeowner or landlord, unless otherwise agreed.

For more specific advice on your home’s suitability for solar panels, try our Solar Panel Calculator, which takes into account your roof’s orientation, size, and location for a personalised estimate.

Your Solar Panel Suitability: Use Our Tool

If all those mentions of east-west orientation and roof pitch are bamboozling your brain, don’t worry. Using our solar panel calculator, we can work out exactly how much energy your roof-mounted panels could generate.

It all starts with finding your property on the map (just enter your postcode). But we’re much more precise than that. Once you’ve located your property, you draw your roof, and tell us roughly what angle your roof is (i.e. steep, gentle or flat). Given those geographic and orientation factors, we can work out how efficient your roof’s panels would be.

We’ll also ask a few questions about your current energy usage and what your house is like. Then, our calculators will get to work and give you an estimate for how much energy you can generate and how much you’ll save, for a range of cost options.