Solfit launches high-performance 425Wp in-roof solar panel that meets the latest UK Fire and Building Regulations

12th June 2025

Solfit, the UK-based manufacturer of integrated solar solutions, has officially launched its

latest product, the JT 425Wp In-Roof Panel, offering a new standard in compliant, high-output

solar technology for domestic rooftops.

Specifically designed to meet the evolving needs of UK housebuilders, developers, and solar

installers, the JT 425 panel brings together enhanced performance, advanced safety features,

and exceptional installation speed. Crucially, it meets the increasingly strict requirements of

UK fire safety and building regulations, including full certification to B Roof (t4) fire resistance

standards that is now a critical compliance point for all in-roof solar systems on new homes.

With a 425-watt peak output, the new panel delivers greater energy generation per module,

reducing the total number of panels required on each roof while helping housing developers

meet Part L regulations for energy efficiency. The panel is constructed using double glass

laminate, a robust design feature that improves fire resistance, extends the panel’s service life,

and eliminates the need for plastic or composite materials.

Installation has also been engineered with simplicity and speed in mind. The JT 425Wp

features Solfit’s patented interlocking metal frame, enabling a secure, watertight fit with

minimal component parts with just 14 in total compared to the 70+ parts required in many

other systems. This significantly reduces labour time and complexity on site. The panel’s

landscape orientation gives installers greater layout flexibility, making it ideal for a range of

roof types and designs.Unlike many alternatives on the market, the JT 425 is completely free from plastic trays, and all

components are made from fully recyclable materials, supporting long-term sustainability

goals and helping reduce construction waste. At the end of its life, every part of the panel can

be processed through existing UK solar recycling schemes.

Backed by UK-based technical support and readily available from UK stock, the JT 425Wp is

designed to meet both immediate installation needs and long-term environmental

responsibilities. It reflects Solfit’s wider mission to power a low-carbon future by providing

solar solutions that are not only effective and compliant but also simple to fit and designed to

last.

Ewen Estill, Owner of Solfit said,

“The JT 425Wp panel was designed by installers, for installers.

Everything about this product has been built with simplicity, safety and performance in mind. With UK

regulations becoming more rigorous, particularly around fire safety, our latest panel provides peace of

mind without compromising on speed or quality.

”

Solfit’s in-roof solar system is already widely used by UK installers and developers, valued for

its aesthetics, installer-friendly design, and full compliance with modern build standards. The

new JT 425 panel builds on that reputation, delivering enhanced output and even greater

practical benefits at a time when regulation, sustainability and efficiency have never been more

important to the UK construction and renewables sectors.

James Parkin, Managing Director of Wheeldon Homes and Solfit customer said,

“Having used

Solfit panels exclusively since Covid for our in-roof solutions, we continue to see excellent aesthetics

and ease of install across our range of properties. Installing a very sorted high-quality product as part

of the overall home to our customers ensures longevity and reliability into the future. All of this is

achieved with minimal install issues and at a reasonable price point.

”

- ENDS -

Notes to Editor:

1. 2. Imagery for Solfit can be found here.

If you require any further information, please contact Holly Woodhead by email

holly@evergreencomms.co.uk or by phone on 07908 173834.

About Solfit

Solfit is a British manufacturer of innovative, roof-integrated solar solutions designed for new

homes and low-carbon developments. With a focus on compliance, performance and

sustainability, Solfit’s patented systems are used by leading developers and installers across

the UK. Every product is engineered to reduce install time, improve visual appeal, and meet the

latest industry standards, powering a low-carbon future, one roof at a time.