Driven by innovation

Sheerline is the innovative brand of aluminium windows, doors and roof lantern systems, designed and extruded by Garnalex. Launched in 2020, the Sheerline system was created to revolutionise the way aluminium windows were fabricated, installed and sold.

Garnalex was formed by Roger Hartshorn (one of the fenestration industries leading figures) in 2018 and is one of only a few UK based aluminium system houses.

Vertically integrated

Our fully vertically integrated, state-of-the-art production facility, enables us to offer outstanding levels of service and agility that Sheerline customers rely on. Giving us the control needed to ensure all Sheerline products are manufactured to the highest possible standards.

With over £19M invested to date

Garnalex’s team of technical experts looked at every aspect of aluminium windows and doors, from how they’re made and installed, how they perform and look, to the service and support required, resulting in the innovative Sheerline range.

We pride ourselves in offering industry leading quality, reliability, and agility of supply, all delivered by our experienced team of fenestration professionals.

Cross section of a Classic Heritage steel look door, highlighted the exceptional thermal performance by overlaying a thermal rainbow to illustrate how Sheerlines wide thermal break gives a low U-value and helps keep homes warm and heating bills lower.

Our Mission

Our mission is to transform what customers expect from aluminium. From design and testing, to the manufacture of every major component at our state-of-the-art facilities, we are passionate about delivering windows that operate, perform and look exceptional, keeping you warm and secure for many years to come.

Made in Britain

From design and testing, to the manufacture of every major component at our state-of-the-art facilities, we are passionate about every element that goes into producing the Sheerline system. With greater control over our supply chain than competitors, we can offer customers more reliable supply and unbeatable service.

Onsite Painting

Continuing our investment in our state-of-the-art production facility, we have recently invested over £1.3 million in our own Qualicoat ‘seaside class’ approved powder coating facility. Bringing the most important secondary process that happens to our Sheerline aluminium range after it has been extruded, in-house to ensure the best quality.

Sustainable at our Core

Our state-of-the-art, energy efficient SMS HYBREX press delivers energy savings of up to 55% compared to traditional presses. Our patented construction method also vastly reduces fabrication waste. This coupled to the high level of energy efficiency built into every product helps build towards a greener future for all.

Built on Experience

Sheerline was founded by Roger Hartshorn, who has more than 40 years experience in the fenestration industry and successfully founded and sold two of the UK’s largest profile systems companies (Eurocell plc and Liniar). Driven by an experienced team of window and door experts, Sheerline is built on solid foundations.

Find out what goes into powder coating every Sheerline product

Our senior team

Roger Hartshorn


Emma Arrell

Finance Director

Ross Hartshorn

Technical Production Director

Dave Watts

Technical Sales Director

Adrian Redshaw

Design Director

Tony Basile

Sales Director

Eddy Webb

Production Director

Steve Musgrave

Operations Director

Adrian Girling

Software Development Director

Key Accreditations

Made in Britain

Made in Britain recognises excellence in manufacturing and promotes British-made products across all sectors. Giving businesses and consumers confidence and clarity that they are buying British.

Quality Management System

The Sheerline manufacturing site has achieved ISO9001: 2015 accreditation, meeting British standards for a robust, quality management system. Demonstrating the strength of our dedicated management processes and procedures.


Sheerline is proud to be a member of The Aluminium Federation, which represents businesses who process, trade and work with aluminium, promoting best practise within the sector.

Approved Applicators

Sheerline underwent thorough approval process, which involved a detailed application outlining every step of the company’s powder coating process and submitting regular samples for testing. Ensuring beautiful, consistent powder coating.

PAS 24 Security

PAS 24 is a standard of testing that measures the security performance of windows and doors in the UK. Developed by BSI (British Standards Institution) its designed to make homes more secure by ensuring that windows and doors are robust enough to resist attack.

Security Accreditation

Sheerline windows and doors all come with optional SBD accreditation. The official UK Police initiative ‘designing out crime’ through physical security.

Our Latest Awards

Oresa Growth Index
9th fastest UK growth

Rising Star
Ben Hartshorn

Managing Director of the Year
Roger Hartshorn

New Product of the Year
Prestige Patio Door

Best Technical Innovation
S1 Lantern Roof

Lifetime Achievement Award
Roger Hartshorn

Best Technical Innovation
Sheerline System

Our reputation is built on trust

Contact us for more information, or to explore the next steps towards becoming a Sheerline customer

Contact us