Our Team

Expertise born of experience

Some of the best technical and operational brains with the most experience in the industry have combined to design and deliver Sheerline, the new aluminium window and door system. Together we believe the team has reinvented residential aluminium windows and doors.

Roger Hartshorn - CEO

Roger Hartshorn


Having successfully built and sold two leading PVC-U systems companies (Eurocell plc and Liniar systems), Roger has fallen for aluminium, for its design possibilities, market potential and recycling credentials.

He and the team are on a mission to introduce the innovations and service to enable fabricators and installers to realise its potential with beautiful, high-performance aluminium windows and doors designed with the fabricator, installer and homeowner in mind.

Emma Arrell - Garner Holdings Finance Director

Emma Arrell

Finance Director

Previously Finance Director of the HL Plastics Group, which includes Liniar, Emma oversees all the financial dealings of the company. With £9 million invested so far in the most modern aluminium factory and facilities in the UK, and a growing team of people, directing and managing that investment makes the Garnalex promise possible.

Adrian Girling - Software Development Director

Adrian Girling

Software Development Director

Ex-Business Micros and Total Glass, Adrian, is creating new software to integrate each stage of the extrusion, manufacture, delivery and assembly processes with our internal SAP system and fabrication aids. This ensures we have full transparency of what and how we are manufacturing for the order, fabrication and OTIF delivery of high-quality aluminium windows and doors.

Ross Hartshorn - Technical Production Director

Ross Hartshorn

Technical Production Director

Ross started as an apprentice in tooling design, manufacturing and maintenance at HL Plastics. By implementing best practice and open communications between departments he learned that it’s possible to improve cycle times, line speed and productivity.

David Lennox - Operations Director

David Lennox

Operations Director

Having worked in the industry for more than 26 years, at Eurocell, Epwin Group and HL Plastics, David brings his considerable experience to the position of Operations Director. It’s David’s mission to deliver product On-Time-In-Full, in PVC, not traditional aluminium-time.

Adrian Redshaw

Design Director

Adrian or ‘Reg’ as he’s better known, was instrumental in the design and development of Eurocell’s many products and then as Design Director was responsible for the design and development of Liniar’s window and door systems. Reg will ensure Sheerline remains at the forefront of practical technical innovation within the industry.

Dave Watts - Technical Product Director

Dave Watts

Technical Product Director

Dave has extensive experience with long spells at HL Plastics, including running Avantek and Vintage Windows. His role as Technical Product Director is to develop fabrication-friendly solutions and introduce innovative ideas based on feedback from fabricators.

Apprenticeship logo

Investing in the future

Many of our design and engineering team came into the industry via the Apprenticeship program and are key to the development of our Sheerline systems. Garnalex are committed to supporting and promoting youth-in-construction and will continue to train a new generation, through a mix of vocational and academic learning; whilst in full-time, paid employment.  If you have a keen interest in the STEM (science, technology, engineering and mathematic) subjects you may be just who we’re looking for.

Research and Development

Research is a critical part of the development of the Sheerline system. The team have spent more than a year investigating the limitations and flaws of current designs in fabrication, installation and sales, developing innovations to overcome them – and the limitations and frustrations of aluminium supply. They examined every aspect of aluminium windows and doors from performance and looks, to how they’re made, installed, and supplied. They’ve re-engineered the aluminium window from the ground up – and every component of the system has been developed in-house to be made in house. The Technical team consists of 6 full time staff with a combined window experience of approaching 200 years. We have a pipeline of products to ensure that the Sheerline product range soon challenges the established players and raises the bar.


The team, including David Lennox and Adrian Girling, are creating the internal process management systems to ensure smooth super- efficient running of the factory, customer ordering and delivery. They have created bespoke new software to work with the Sheerline system, so it’s easier by far to fabricate high-quality aluminium windows and doors.


The manufacturing team, headed up by Ross Hartshorn – Technical Production Director and Sergio Sa – Factory Manager, have overseen all aspects of the new state-of-the-art factory build. This includes designing the layout of the new plant, the equipment, tooling and maintenance, and helping to design the internal process management system, and overseeing production.

Sales and Marketing

A primary aim in the development of Sheerline is to make it easier for fabricators and installers to order and sell residential aluminium windows and doors. That means high quality, short lead times, and reliable service. The unique nature of the Sheerline system calls for a unique approach to marketing, which is headed up by David Wigley, an industry veteran with a wealth of experience in brand building. Sales & Marketing Manager Eilidh Hudson brings experience from the aluminium sector and works across both disciplines. Because Sheerline is fabricated differently from other aluminium windows and doors, fabricators need to learn the Garnalex philosophy and how to fabricate them. Our Ambassador Workshops take fabricators and installers to the heart of this new philosophy – to meet the Sheerline team and tour the new factory, where it is obvious that this is #AluminiumButNotAsYouKnowIt.

Customer Service

Great service is at the heart of the Garnalex promise. Fabricators and installers who make and sell aluminium windows and doors to homeowners know how expectations have changed in the Internet Age. Waiting weeks for anything is frustrating and not very business friendly. We aim to be very customer focused and friendly, so Sheerline customers can keep their customers happy and grow.

Our experienced customer service team will be the first point of contact for fabricators and installers. Responsible for sales processing, product information, customer feedback and general enquiries, they aim to provide a seamless customer experience.