From Mohamed Merchant, Associate Director at TÜV SÜD’s UK Real Estate Facade Access division, an international building services engineering consultancy, specialising in sustainable MEP (mechanical, electrical and public health), BIM (Building Information Modelling), lighting design, and vertical transportation.
Architectural design is evolving rapidly, with ever more elaborate performance-specific building envelopes creating iconic buildings the world over. But of course, for the outside of a building to maintain its aesthetic appeal, it must be regularly cleaned, inspected and maintained. Economical and effective façade maintenance is therefore now a prime consideration within the overall building design process.
However, often the need for facade access systems are realised post structural and MEP design freeze. Concomitantly, the systems are expected to meet the architectural intent by remaining hidden when not in use. This typically restricts the likelihood of designing an optimised and integrated facade access system, resulting in increased costs to the client.
This means that architects face the double-edged challenge of creating an iconic building that also delivers on the more practical, long-term demands of façade cleaning and maintenance. Bespoke maintenance systems must be effectively blended within a tight operating space, whilst also allowing façade panels and MEP plant components to be replaced.
The development of a façade access strategy must therefore be incorporated within architectural design at an early stage and cover the expected life of a building. If façade access equipment (FAE) is treated as an afterthought, trying to work maintenance requirements around inappropriate design decisions can be hugely inefficient and costly. It may even end up failing to comply with industry standards.
A FAE system must perform as expected from the outset and take minimal assembly time, without any health and safety risk to operatives working at height. If the FAE is not designed appropriately during the pre-construction phase, or incorrectly installed, this can have a significant and escalating financial impact, such as a requirement for highly skilled maintenance staff and industry-specific training.
Of course, working conditions will vary from site to site and country to country. For example, in the UK Health and Safety Executive requirements cover the key risks that could impact on maintenance activity. These include height to be negotiated, complexity of the building façade, duration and extent of work, required cleaning frequency (dictated by façade warranties), location, weather conditions, building surface, ground condition, level of cleaning and maintenance activities.
Where hazards cannot be eliminated, to ensure that maintenance can be carried out safely, suitable control measures should be incorporated into the design to manage and minimise associated risks. If the architectural team consider work at height issues too late in the design process, the likelihood is that detailing of maintenance access will be inappropriate, and therefore less suitable for maintenance crews. This is likely to create additional building lifetime operating costs, as a result of redesign, structural alterations and inappropriate façade access arrangements. Those responsible for FAE design should also communicate the access strategy with the lead design team, using drawings, sketches, written schedules and specifications in an agreed format.
The National Bank of Kuwait’s 300-metre-high headquarters presents a real-world example. For this project we supported the façade access development, from initial concept to on-site completion, including the design of a highly complex building maintenance unit system (BMU). To maintain warranties and support glass replacement, the BMU gives periodic access to the external elevation, including the ‘crown’ of the building. Several access options were explored during the design stages to fit the requirements of the building geometry and maintenance services.
On a practical level, FAE also needs storing when it is not in use. So, visibility and garaging problems can also arise if this element is not considered during the building design phase. As ageing FAE poses a significant risk, it is vital to ensure that its integrity is retained throughout the lifespan of the building. An environmental study at the early design stage should therefore specify the minimum required level of protection and finishes, such as waterproofing, galvanising and paint. Permanently installed FAEs should ideally be stored in a weatherproof environment and parked FAEs must not encroach upon the building’s line of sight. Maintenance zones and clear space for periodic inspection and testing of FAE should also be considered.
As multiple aspects of the design process will impact the final façade access solution and its long-term viability, experienced façade access designers should be involved in the early stages of the building design process and have direct discussions with the architect. This will help to ensure that the ultimate FAE solution minimises operational hazards and costs, without impacting a building’s aesthetic design.