Eddie Robinson, managing director of Smart Architectural Aluminium looks at the use of aluminium door, window and curtain walling systems when specifying for a refurbishment project
The use of aluminium in construction projects has grown to such an extent that it is now the second most widely specified metal in buildings after steel. Used in a wide range of projects, across both the public and private sectors and from residential to commercial schemes, around 40 per cent of all the 375,000 tonnes of aluminium produced in the UK goes in to the building sector.
This rapid rise has been on the back of a range of intrinsic properties and advantages: it is manufactured from alloys that are corrosion-resistant; weather-proof and resistant to harmful UV rays; as a building material aluminium delivers robust performance over a long period of time, with very limited maintenance requirements. Widely acclaimed for its aesthetic properties, aluminium is one of the most durable and flexible building materials, yet its impressive sustainability credentials are much less well recognised, despite the fact that over two-thirds of all the aluminium ever produced is still in use today – the majority of it having been recycled or reused at the end of its useful life.
While always a key material for the new build sector, recent years have brought a significant growth in the use of aluminium systems in refurbishment projects, with manufacturers regularly developing and introducing new products and systems to meet the specific needs of these often sensitive applications. The majority of aluminium products used in heritage and refurbishment projects are window and door systems, with the architect and planner often requiring a closely matched aesthetic to the systems being replaced (very often, these are traditional steel units with their recognisable slim sight lines and art-deco appearance).
With an exceptionally high strength-to-weight ratio, aluminium is the ideal modern alternative for such applications, with both window and door systems available to provide the narrow frames necessary to meet these aesthetic requirements.
Not only can these systems match the slim profiles and lines of traditional steel doors and windows, but they can also provide significant performance advantages, combining elegant aesthetics with outstanding thermal performance. With slim, thermally-broken profiles, windows are available in a number of formats, including fixed-pane, sash and casement options, to provide the architect, building owner and facilities manager with great flexibility in terms of both design and ongoing operation. The benefits of working with a modern material also means that additional features can be provided; for example a wide range of door furniture and locking options are available, with many of the security features able to be concealed within the system’s frame – making for cleaner, more elegant sight lines.
One recent project to have benefitted from the use of aluminium systems is the Royal Mail’s landmark Mount Pleasant sorting office in central London, which has recently undergone a major modernisation programme. This has seen all the old uPVC windows in the main administration building replaced with new aluminium windows and doors, these products having been selected to bring back the aesthetic appeal of the building’s original fenestration. The building originally featured large bronze windows, but in a 1980s refurbishment, these were replaced with white uPVC units.
The scheme’s architect, Boyes Rees, wanted to reintroduce the distinctive, slim sight lines and bronze appearance of the original windows, features that had been lost through the use of uPVC, and so specified aluminium windows for the exterior facades. Each of the window units is an impressive 8m wide by 4.5m high and was manufactured in a dual colour format, with the external profile featuring a bronze polyester paint finish and the internal profile standard white.
Given the exceptional scale of each window unit, and their corresponding performance requirement, a bespoke, 85mm coupling mullion had to be developed to reinforce and strengthen the system, while retaining its characteristic slim profile.
Systems manufacturers not only invest in product development, but also in the introduction of a broad range of surface finishes, including anodized finishes, polyester powder coating and dual colour options (as specified for Mount Pleasant), with the leading manufacturers bringing the entire process in-house to ensure complete control of the quality of the finished product.
As with any material, quality is of supreme importance – both throughout the manufacturing process and of the finished product. In this regard, systems companies subject their products to a rigorous quality regime, from the raw extrusion right through to the finished profile. It is this focus on every aspect of the product that has led specifiers, contractors and installers to increasingly value the qualities that aluminium systems can bring to new build and refurbishment projects, from elegant aesthetics to improved thermal performance and assured long-life.