Yes. Sheerline Prestige windows are designed with Thermlock® multi-chamber technology, which improves insulation and reduces heat transfer through the frame. They can achieve U-values around 1.4 W/m²K with double glazing and around 1.0 W/m²K with triple glazing, helping to keep homes warmer and more energy efficient.
Sheerline Prestige Windows – Chic and inviting aluminium windows crafted through innovation.
Prestige windows provide an extensive selection of options, making them ideal for a diverse array of projects.
Performance & Design
Outstanding Thermal Efficiency. Elegant Design.
Energy-efficient aluminium windows combining contemporary styling, dependable performance and a wide choice of finishes.
The King’s Award for Enterprise: Innovation 2025
Key Features
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Optimal Thermal Performance
U-values from 1.4 W/(m²K) with double glazing and 1.0 W/(m²K) with triple glazing.*
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A+ Window Energy Rating
Up to an A+ Window Energy Rating, achievable with suitable triple glazing.
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Part L Compliant
Designed to meet applicable Part L requirements when correctly specified and installed.
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25-Year Paint Finish Guarantee
A durable finish backed by a 25-year paint guarantee, subject to terms.
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10-Year Manufacturer’s Warranty
Added peace of mind with a 10-year manufacturer’s warranty, subject to terms.
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Extensive Colour Choice
Available in a wide range of colours and finishes to complement your property.
*Thermal values and energy ratings depend on glazing and window configuration. Guarantees and warranties are subject to the manufacturer’s terms and conditions.
Stylish aluminium windows that combine exceptional thermal performance with refined looks

Sheerline Prestige Windows our most thermally efficient and versatile 72 – 80mm wide system, is available in casement, French, tilt & turn and fixed window styles, and has been designed to be sympathetic to the modern trend for light, airy interiors. Using slim sashes allows more light to flood into your home, helping create that important sense of space and tranquillity.
- Tilt & Turn Windows: 95mm, 109mm, 119mm sightlines
- Casement & French Windows: 88mm, 102mm, 112mm sightlines
- Picture Windows: 46mm, 60mm, 70mm sightlines
Patented Construction
Our patented construction method – using threaded screws to bind corners tightly together – helps eliminate misaligned corner issues that can occur on ordinary aluminium frames. This allows each window to be individually hand tuned to perfection. Leaving you with the perfect balance of understated refinement coupled to exacting quality standards, where no detail’s overlooked.
Great quality products along with great customer service. Easy to recommend.
Inbuilt Security
Prestige’s full depth eurogroove also enables us to offer the latest high security, multipoint locking – helping keep you and your home safe and secure. Additional features like unique hinge protectors also help create exceptional levels of security. For added peace of mind choose our laminate glass upgrade – for Secured by Design accreditation –the official UK Police initiative ‘designing out crime’ through physical security.
Featuring Unique Thermlock® Technology
Prestige combines aluminium’s clean lines with exceptional thermal performance for up to an A+ Window Energy Rating. Our innovative Thermlock® multi-chamber thermal design, hidden away inside each window and door, helps keep you and your property well insulated against the worst of the UK weather. These closed-cell, insulating chambers act as a thermal break and work in conjunction with high performance glazing to create class leading thermal performance, far superior to traditional polyamide thermal breaks.
A Choice Of 3 Outer Frames
In a choice of ‘flush’ and ‘standard’ styles, enables Prestige to accommodate a wide variety of installation situations and plaster reveals.
Prestige comes as standard with concealed drainage and an optional concealed ventilation shroud for improved, discreet aesthetics.
Available in a range of colours and finishes
to suit every home.
Document Downloads
Sheerline Prestige Brochure
FIND MATCHING DOORS
We offer a wide range of complementary doors, designed around our core chassis to ensure everything matches perfectly, and performs to the same exacting standards.
Latest projects
CONTEMPORARY WINDOWS
Early 70's Property Renovation, Windermere – Contemporary Glazing
CONTEMPORARY WINDOWS
Contemporary Aluminium Glazing, Louper Weir, Lake District – New Build
Ready to transform your home?
Get a made-to-measure quote for your Prestige Windows today. Our team will guide you through sizes, styles and glazing options to find the perfect fit for your home.
Or call us on 01535 603909 to speak with our team.
Frequently Asked Questions
If you require any support, please don’t hesitate to review our FAQs below or drop us a message on our contact form here
Are Sheerline Prestige windows energy efficient?
Are Sheerline Prestige windows secure?
Yes. These windows include multi-point locking systems, hinge protectors, and a full-depth eurogroove, which allows for high-security hardware. They can also meet Secured by Design standards when upgraded with laminated glass for additional protection.
What information must be provided in order to get an accurate quotation?
We will ask you to provide the following information:
- Approximate dimensions (width x height)
- Basic design/layout
- Project location
How long will my quotation take?
We aim to return all quotations within 24 hours however large projects may take longer.
Come and explore…
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