Offsite manufacturing has undergone a reputational boost over the past few years. Yet some people remain resistant to the idea that the process is key to creating the sustainable homes our low-carbon future depends upon. Simon Griffiths, Head of Offsite Construction at Sika UK dispels some long-standing myths associated with modular building.
Our perception of people, places and other things that make our world go round is either gleaned from personal experience or the informed wisdom of others. In terms of offsite manufacture, it has taken a good while to establish its reputation as a reliable, cost-effective, sustainable building method, due to its use in creating the rather drab, rickety prefabricated homes which sprung-up in the 1950s and 60s. Generally, the properties were viewed as poorly constructed with a thermal performance to match. This tainted some people’s view of offsite construction, which has since undergone a deserved renaissance thanks to manufacturing innovations and the increasing quality and availability of products specifically tailored to the offsite construction market.
Tighter control leads to higher building standards
Offsite construction is rapidly gaining renown for its quality, due to it taking place in safe, factory-controlled conditions unhampered by poor weather and on-site hazards. This improves build consistency and accuracy, with correct procedures being able to be repeated, ensuring properties are constructed to the same high standard. The level of performance is partly due to the tighter tolerances enabled by offsite construction building in comparison to traditional methods.
This greater precision means properties are built as-designed, an outcome that is particularly crucial to their thermal performance. This gives credence to the notion that although offsite construction costs can vary, the modular model pays long-term dividends in the form of lower energy bills and a reduced risk of future refurbishment due to factory-controlled application. Each of these outcomes helps minimise a building’s whole life costs.
The need for more offsite awareness
Despite the innovation of digital modelling systems such as BIM revolutionising the design process for specifiers and architects – a method that is tailormade for modular construction – offsite building does not exceed 20% in the world’s major housing markets.1 Countries such as Sweden are an outlier in this sense, with more than 80% of its new homes being built using some form of offsite construction since 2018.
A lack of awareness of the benefits of modular methods could account for its relatively low practice on a global scale. In the UK at least, it’s an issue the government is looking to counter with building initiatives such as the Department for Education framework. Announced in March 2021, the £3bn scheme is heralded as an ‘evolution’ in standardising the construction of school buildings using offsite methods. Modular building also features as part of a £4bn Ministry of Justice (MoJ) plan to create more prison places. Issued in December 2021, the Prisons Strategy White Paper states around 70% of MoJ prisons are built offsite, with a proposal that future builds will be ‘zero net carbon ready from day one’.
With non-traditional methods playing more of a role in the creation of our publicly-owned structures, it would appear that the UK government views offsite construction as part of a solution to our future building needs. Estimated to be 50% quicker than building from the ground-up using bricks and mortar, modular methods could prove crucial in fulfilling the government’s pledge to build 300,000 homes per year to help solve the UK’s ongoing property crisis. Whilst being able to build to tighter tolerances and improve a property’s airtightness and overall energy efficiency – outcomes that are achieved more readily via offsite construction methods – could prove significant in helping the government meeting its highly publicised net-zero carbon target by 2050.
Yes, offsite manufacture has come a long way since its post-Second World War origins and the creation of houses that gave the term ‘prefabricated’ a rather dubious name. The modular model is now part of the future; we have the talent, technology and products to manufacture such homes and other commercial buildings to suit any design and environment. The myth that offsite building cannot match anything a traditional bricks and mortar method can achieve in terms of building and energy standards, we believe has now been dispelled.
For more information on how Sika’s offsite division can help your next building project, visit: https://bit.ly/OffsiteBrochure