If you’re researching solar for your home in Essex, Kent or the wider South East, you’ve likely come across in-roof solar panels – sometimes called integrated solar.
They’re often positioned as a more visually appealing alternative to standard systems, but appearance isn’t the only factor. The way they’re installed, how they perform and when they make sense all matter.
This guide breaks it down in practical terms – so you can make a properly informed decision.
What Are In-Roof Solar Panels?
In-roof solar panels are designed to sit within the roof structure itself, rather than being mounted above it. Instead of fixing panels on top of tiles, part of your roof covering is removed and replaced with a solar integration system. The panels then sit flush within that space.
Functionally, they still generate electricity in the same way as any other solar PV system – the difference is purely how they’re incorporated into your roof.
In-Roof vs On-Roof Solar: What’s the Difference?
The core distinction comes down to installation method and system behaviour.
Appearance: in-roof sits flush with the roofline for a cleaner, more seamless look, while on-roof is mounted above the tiles and more visible from ground level.
Installation Complexity: in-roof solar is more involved, it forms part of the roof structure and a roofer and solar roofer is required. On-roof is faster, more straightforward and less laborious.
Cooling and Performance: on-roof systems benefit from airflow beneath the panels, helping keep temperatures lower. In-roof systems run slightly warmer, which can marginally reduce output.
In UK conditions, the difference is typically small, often just a few percent across the year – but it’s still worth factoring in if maximising generation is your priority.
Will In-Roof Solar Panels Cause Roof Leaks?
This is the most common question we get asked at SolarTherm UK in regards to integrated solar – and rightly so. A properly installed in-roof system should not compromise your roof’s weatherproofing. Modern integrated systems are designed to maintain full watertight integrity and withstand UK wind and rain conditions. All solar installation by SolarTherm UK meet fire and structural safety requirements as standard.
The key variable isn’t the technology – it’s the installation quality.
At SolarTherm UK, we’ve been installing solar PV systems since 2010, and the difference between a long lasting system and a problematic one almost always comes down to design and workmanship, not the product.
Do In-Roof Systems Require Drilling?
All solar installations require securing components to the roof structure, whether in-roof or on-roof. With in-roof systems sections of tiles are removed, mounting frames are fixed into the roof structure, with the integrated system replacing the removed tiles. This is a planned structural installation, not surface level fixing, and is designed to meet UK building and roofing standards.
How Are In-Roof Panels Installed?
While not a DIY job, understanding the process helps set expectations. A typical installation includes:
- Roof Assessment: checking structure, pitch, condition and orientation
- Bespoke System Design: matching the integration system and panel layout to your roof type
- Tile Removal: opening the section where the system will sit
- Integration System Installation: fitting the in-roof framework and weatherproofing components
- Panel Installation and Electrical Work: connecting the system safely to your home and testing performance
For UK homeowners, it’s essential to use an MCS certified installer, who will ensure the system is suited to your specific roof and check planning constraints where applicable.
When Do In-Roof Solar Panels Make Sense?
In-roof systems aren’t always the default choice – but in certain situations, they’re a very strong fit. They work particularly well if you are building a new property or replacing your roof, or if you want to prioritise aesthetics, especially on visible roof elevations.
When Are Standard Panels the Better Option?
In many cases, traditional on-roof systems are still the most practical solution. They’re often preferable if your roof is in good condition, you’re aiming for maximum efficiency and you want a quicker, less invasive installation. An added bonus for an on-roof system is they tend to be cheaper and easier to install.
A Practical Way to Decide
A simple rule of thumb:
- Already doing roof work or want a flush finish? Consider in-roof
- Retrofitting onto an existing roof and want efficiency and simplicity? On-roof is the better option
Why Installation Expertise Matters
Not all solar systems – or installers – are equal.
At SolarTherm UK:
- We’ve specialised in solar since 2010
- We design bespoke solar and battery storage systems – not off the shelf packages
- We install across Essex, Kent and the wider South East
- Every system is tailored to your property, usage and long term energy goals
That means you get a system that’s designed to perform – not just one that fits.
Final Thoughts
In-roof solar panels can be an excellent solution in the right scenario – particularly where aesthetics or roof work are already part of the plan. But they’re not automatically “better” – just different.
The best approach it always to assess:
- Roof condition
- Your priorities (appearance vs performance vs cost)
- Your long term plans for the property
That’s where a properly designed system makes all the difference.
If you’re ready to start your journey into solar, contact SolarTherm UK today for a free, no obligation quote and design, tailored to your property, usage and future energy needs. No hard sell, just honest, expert advice – and the time you need to make an informed decision.
Your home. Your energy. Your future.
FAQs
Are in-roof solar panels more expensive?
Yes, typically. Installation is more complex and involves additional roofing work, which increases upfront cost compared to on-roof systems.
Do they generate less electricity?
Slightly, in some cases. Because they run warmer, output can be marginally lower—but the difference is usually small in the UK climate.
Are they suitable for all roof types?
Not always. Suitability depends on roof structure, pitch, and covering (tile vs slate). A survey is essential.
Can I add a battery to an in-roof system?
Absolutely. In-roof panels work the same electrically as standard systems, so they can be paired with battery storage to maximise self-consumption.
Do I need planning permission?
Most installations fall under permitted development, but you may need approval if your property is listed or in a conservation area.
