Experts in Aluminium Window & Door Fabrication

Customer First Service

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24hr Quotations

FREE Nationwide Delivery

We specialise in the supply and manufacture of bespoke aluminium windows and doors. Our purpose is to supply high quality products, delivered on time every time, and at competitive prices. We pride ourselves on being reliable, efficient and easy to deal with. We offer an extensive range of premium aluminium products, including slimline bifolds, patio doors, internal screens, commercial glazing and much more.

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Smart Alitherm 400 Windows

Smart Alitherm 400

Featuring Smart’s innovative co-extruded glazing gasket for quicker installation, the Alitherm 400 offers versatile configurations and compliance with PAS 24:2022 and Building Regulations Document L, ensuring superior security and thermal insulation.

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Why Choose BDC?

Diverse
Product Range

By choosing BDC, you’ll have access to a wide range of products, meaning there’s no need to dual or triple source your inventory.

Over 15 Years
Industry Experience

We have built a reputation for excellence with our suppliers and our customers, enabling you to benefit from our technical expertise.

British
Supplied & Made

Our suppliers are all based in the UK, manufacturing the highest quality products on the market.

Dedicated
Manufacturing Facility

We manufacture all of our products to the highest standards at our 27,000 sq feet dedicated facility in Witham, Essex.

Delivering
Far & Wide

We deliver throughout the south of England, to any location from Birmingham to Truro, meaning you can rely on us as your single-source supplier.

Our Most Popular Products

Smart Visofold 1000 Slim

Smart Visofold 1000 Slim

The Smart Visofold 1000 Slim is a sleek aluminium bifold door system designed to maximise natural light with its ultra-slim profiles and narrow sightlines. Offering excellent energy efficiency and easy installation with Smart’s innovative Quick-Glaze bead system, this versatile door is suitable for both residential and light commercial applications.

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Smart Visoglide Plus

Smart Visoglide Plus

The Smart Visoglide Plus Patio Doors combine modern styling with robust performance, making them perfect for residential and commercial applications. These aluminium sliding doors feature slim sightlines and can accommodate large glass panels to create expansive openings in any space.

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Smart Alitherm 600

Smart Alitherm 600

Our most popular window, Smart’s Alitherm 600 offers a high-quality glazing solution for a range of applications. With superior thermal efficiency thanks to Smart’s innovative polyamide thermal break technology, these windows provide excellent performance while maintaining a sleek, modern design.

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Commercial Projects

Large Scale Commercial Contracts

Large Scale Commercial Contracts

Whether it’s large commercial buildings, replica-refurbishments or new building contracts, we cater to any requirements. We provide tailored solutions for projects such as office buildings, retail developments, and educational establishments. Get in touch today – we’d love to hear about your project and its requirements, as well as answer any questions you may have.

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Newsletter

Alitherm Windows – Features & Benefits
8 days ago News

Alitherm Windows – Features & Benefits

BDC Aluminium is your trusted supplier of premium aluminium fenestration products. With a wide-ranging portfolio designed to meet the needs of builders, architects, and construction professionals alike, we pride ourselves on delivering quality, performance, and style. You probably don’t need us to explain just how important windows are to a building’s façade. Whether residential, commercial, or public, the external face of any structure sends a clear message to those who pass by or approach it. That first impression matters—and well-designed windows play a crucial role in defining a building’s character, energy efficiency, and overall appeal. In this article, we’re showcasing one of our most popular aluminium solutions: Alitherm Windows. We’ll guide you through their versatile designs, highlight key features and benefits, and explain why partnering with BDC Aluminium is the smart choice for your next project. What Are Alitherm Windows? Our Alitherm Windows—featuring Alitherm Heritage, Alitherm 400, and Alitherm 600—are crafted using profiles from Smart Systems, the UK’s leading supplier of aluminium glazing solutions and bespoke extrusions. With over 40 years of industry expertise, Smart is renowned for innovation, design precision, and technical excellence. Their systems are trusted across the UK for delivering high performance, reliability, and sleek aesthetics in both residential and commercial settings. When you choose Alitherm Windows from BDC Aluminium, you’re not just investing in premium aluminium systems—you’re partnering with two names synonymous with quality, consistency, and long-term value. Thanks to the versatility of our Alitherm range, we have the ideal solution for virtually any construction project. Whether it’s a new build, refurbishment, or a residential or light commercial development, Alitherm Windows deliver the performance you can rely on. So, what exactly makes them stand out? Superior Thermal Efficiency Achieving a low U-value is more important than ever when selecting a window provider, especially in today’s climate of rising energy costs. For energy-conscious construction, you can count on BDC Aluminium to deliver high-performance, thermally efficient solutions. Each of our Alitherm Windows offers impressively low U-values. Alitherm Heritage, for instance, achieves 1.6 W/m²K—a remarkable performance given its slim sightlines and traditional, period-inspired aesthetic. It’s the ideal choice for preserving the architectural character of listed buildings, heritage homes, and refurbishment projects, where maintaining a period look is just as important as meeting modern efficiency standards. Alitherm 400 achieves a U-value of 1.4 W/m²K, while Alitherm 600 performs even better, reaching as low as 1.3 W/m²K. This outstanding thermal performance is made possible by Smart’s innovative polyamide thermal break technology, which enhances insulation and supports compliance with the latest energy regulations across a wide range of applications. Strong, Safe and Durable Performance only matters if it stands the test of time. That’s why all our Alitherm Windows are constructed from premium-grade aluminium—an inherently strong, low-maintenance, and long-lasting material that far outperforms uPVC or timber when it comes to durability and stability. Security and compliance are built into every product. Our Alitherm Windows are BSI certified, meaning they meet internationally recognised standards for quality, safety, and operational performance as set by the British Standards Institution. They’re also PAS 24 accredited, confirming they’ve passed rigorous testing against forced entry. With these credentials behind them, our Alitherm Windows offer peace of mind alongside outstanding longevity and visual appeal. Why Choose BDC Aluminium’s Alitherm Windows? At BDC Aluminium, we combine product excellence with dependable service. From quotation to delivery, our team is dedicated to supporting your project with expert advice, precision fabrication, and a focus on getting the details right. Whether you're designing a contemporary new build or preserving the charm of a historic property, our Alitherm Windows range provides the flexibility, performance, and results you can trust. Let’s Build Better, Together Ready to enhance your next project with the performance, design freedom, and long-term value of Alitherm Windows? To get started, fill out our contact form or give us a call on 01245 474747—we’ll be happy to help you find the right solution. Aluminium built for performance. Solutions built for you.

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