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A big concern for people who are starting to think about adding solar to their home is ‘What roof is best for solar panels?’ It’s logical to assume that solar works best on south-facing roofs; in an ideal world, you’d add your panels to a south-facing pitched (slanted) roof set at 30-40 degrees, covered in clay tiles.

But it’s important to know that solar can work well on many different roof types. What counts more than roof type is the system itself, and how it’s designed to meet your needs – and that’s where we come in. We’ve created systems for all kinds of roofs and properties, so we recommend you talk to us even if you think your roof isn’t suitable.

In this guide, we’ll show you the best roof types for solar panels – and how the less-than-perfect roof types can still work beautifully to cut your bills and give you a reliable source of clean, renewable energy…

What is the best roof angle for solar panels?

Around 40 degrees from horizontal is the sweet spot for most UK homes – and the good news is, most roofs here are angled at 30-50 degrees. A 2019 University of York study tested 3,600 systems across Yorkshire and found 39 degrees gave the best output there.

But your roof doesn’t need to hit this figure exactly. Anything between 30 and 40 degrees works well, and we adjust the mounting frame to correct for a shallower or steeper pitch where needed.

Where is the best place to put solar panels?

South-facing is best, ideally clear of shade from trees, chimneys or neighbouring buildings. That said, east- and west-facing roofs still do a solid job, generating good output across the day. An east-facing roof will catch more sun in the morning, while a west-facing one will get more in the afternoon and evening.

North-facing roofs generate less energy but can still work, and a north-east or north-west slope can still pull its weight as part of a bigger system. We can add micro-inverters or power optimisers to your system to ensure it runs as efficiently as possible.

During the quote process, we’ll look at your roof’s orientation, angle and any shading before recommending a layout.

Installing solar panels on a flat roof

Flat roofs aren’t a problem, and they come with a genuine advantage. Because the panels sit on a tilted frame rather than following the roof’s pitch, we can angle them for maximum output no matter which way your property faces.

So, can solar panels be installed on a flat roof? Yes, though a few extra steps apply. Most flat-roof systems use heavy weighted frames instead of roof fixings, at around 80kg per panel compared with roughly 20kg for a standard fixed panel, which makes the system about five times heavier. That’s why every flat-roof job starts with a structural assessment to check that your roof can take the load without any damage.

We also keep panels a set distance from the roof edge, and space each row of panels so one doesn’t shade the next. Both of these factors affect how many panels will fit, so we design the layout around your roof rather than working to a standard template. And since December 2023, most flat-roof solar installations no longer need planning permission under updated government permitted development rules – so that’s one less thing to think about. You can learn more in our blog on planning permission for solar panels.

Can solar panels be installed on a slate roof?

Yes, though slate calls for a bit more care. It’s a durable, long-lasting material, but it cracks more easily than concrete or clay tile under standard fixings. We use slate-specific mounting hooks that spread the load and avoid damaging individual tiles.

It’s a slower, more careful job than most, but the finished system performs just as well as on any other roof.

What roofs are not suitable for solar panels?

A few roof types just won’t work. The fire risk on thatched roofs is too high, and they don’t have a proper way to fix a mounting system, so we steer clear of them. Wood shingle roofs are similarly fragile and fire-prone. And of course, roofs with asbestos need specialist removal before any work can start, since drilling into asbestos is a serious health hazard.

Beyond materials, a roof that’s in poor condition, or one with heavy, permanent shading, won’t give you a good return, no matter what it’s made from.

But none of this means solar is off the table. If your roof falls into any of these categories, we can look at bespoke alternatives instead, such as a ground-mounted system or even a purpose-built pergola. We love coming up with creative solutions, so always ask us what’s possible before you rule solar out!

So, what roof is best for solar panels overall?

There’s no single perfect roof. But if you’re starting from scratch, a south-facing, unshaded, pitched roof between 30 and 40 degrees, covered in concrete or clay tile, gives you the strongest foundation. Flat and slate roofs both work well too, just with a bit more design thinking built in. The roofs we’d steer you away from are thatch, asbestos, wood shingle, or anything in poor condition – but this is where ground-mounted solar can be the perfect solution.

Every roof is different, and the only way to know what’s right for yours is a proper site visit. We’re MCS-accredited and follow the Renewable Energy Consumer Code (RECC), so you can trust every assessment we make. Get in touch and we’ll take a look at your roof, then design a system built around your property and needs.