esign for Manufacture and Assembly is an approach that facilitates greater off-site manufacturing – vastly reducing on-site construction. Structural timber buildings are constructed with higher levels of speed and safety – the process delivers both resource and cost efficiencies but does not impede creative design, aspirations or compromise on quality.
According to the Smart Construction report, researched and published by KPMG, the construction industry has seen a substantial increase in pipeline activity, with greater significance placed on sustainability – playing to the strengths of structural timber systems. Growth is being driven by demand for infrastructure, public and private housing and commercial buildings. While the construction industry is buoyed by predicted growth and expansion, it continues to underperform in four strategic areas: productivity, certainty in delivery, skills shortage and data transparency.
Off-site construction – the prefabrication, modularisation and standardisation of construction processes and assets within factory-controlled environments – continues to be quoted across Government and industry as a potential catalyst in meeting these challenges. Off-site structural timber construction, supported by DfMA techniques, offers a viable solution by presenting transformative improvements across the asset lifecycle in time, cost, quality, health and safety. But most importantly, off-site structural timber construction offers predictability.
As well as delivering projects faster, lowering costs together with improving quality and sustainability, the use of DfMA techniques also results in better operational and in-use outcomes. The recent RIBA Plan of Work incorporating Designing for Manufacture and Assembly was developed to help the industry take the next evolutionary step towards ‘assembly’ rather than ‘construction’.
Historically, many have questioned why the built environment sector does not reflect the manufacturing methods of the aerospace and automotive industries; where cars and planes are assembled in huge factories predominantly by robots.
Innovations in panelised timber systems and modular timber components, supported by new off-site manufacturing technology with semi-automated assembly production processes now make this achievable to some extent. However, size limitations are dictated by transportation restrictions and there has to be a mindset and process change, now that buildings no longer have to be constructed in situ – this is where the RIBA Plan of Works and Assembly overlay comes in.
The plan identifies seven core stages of the build process, from the preparation of the brief and concept, to technical design and construction stages. These stages are mapped out against core objectives such as the DfMA strategy, the integration of Building Information Modelling (BIM) and procurement tasks for DfMA.
Crucial to DfMA principles, information transfer and share, designing with BIM is a collaborative way of working, underpinned by the digital technologies which unlock more efficient methods of creating and maintaining assets. BIM embeds key product details and asset data to create 3D models that can be used for effective management of information throughout a project lifecycle – from earliest concept through to operation.
3D models can be shared by construction partners with further detailing being added along the design journey. BIM technology and CNC machines ensure structural components are manufactured to exacting tolerances to guarantee the details of connections are precise. This is of particular relevance in hybrid structures where high levels of technical advancement, innovation and rigorous planning through a strict programme of works are required to ﬁnish builds on time.
At a time when our industry is facing a skills shortage, taking the build off site into a factory-controlled environment reduces the levels of resource required and is not dependent on traditional construction skills. Developing solutions that are ‘assembled’ rather than ‘constructed’ offers the prospect of using fewer people in a more controlled and safer environment.
The Structural Timber Association
According to the findings of a recent survey by the Structural Timber Association, 74% of the UK’s contractors, developers, architects and registered providers revealed they plan to increase specifications of structural timber. As a robust yet lightweight solution, the use of structural timber reduces the loading on foundations and delivers multiple benefits including speed of build, enhanced quality, together with improved thermal, acoustic and performance benefits. There is a wealth of information available to construction professionals on the Structural Timber Association website, from advice on structural timber systems to market reports and an online member’s enquiry system.