Ken O’ Neill, Business Development Manager for Offsite from Sto discusses the benefits of marrying offsite construction with external wall insulation (EWI) and how collaboration is creating faster, simpler and more efficient production processes.
As the urgent need to build more homes increases, offsite construction has a key role to play. Prefabricating components and structures in a factory enables homes to be delivered more quickly and with greater control. Quality can increase as can efficiency, safety standards and sustainability credentials.
To maximise the benefits of prefabrication, collaboration with specialist manufacturers is essential. This will ensure systems used in the process meet the specific needs of modular developers and contractors while keeping production schedules on track.
Highly versatile, external wall insulation (EWI) and rainscreen cladding (RSC) systems are ideal for off-site construction. They can be factory applied to a wide range of structural panels, including timber and steel framed structures. Once the EWI or RSC is installed, a wide range of façade finishes can be achieved using render, colours and textures, and brick slips.
Engaging with an EWI manufacturer in the project’s early design stages is essential. Through expert, customer-focused teams, the most appropriate system can be prototyped and developed. The substrate build-up and the components needed to meet the project’s specific performance requirements such as thermal efficiency and aesthetics must all be considered.
Ensuring all these components work together as a system is essential to ensure it performs as expected once installed and will meet UK Building Regulations. For this reason, it is strongly advised to work with a single supplier and avoid changing the design or substituting products at a later point in the process.
In line with this need, manufacturers are developing components offering cost and productivity benefits too. One example is the StoVentec carrier board which is significantly lighter than traditional third-party cement boards. This makes it much quicker and easier to transport and install.
After the design has been established, an experienced EWI manufacturer will be able to provide technical guidance and support in advance of any testing throughout the production process to provide faster cycle times, higher degrees of automation, consistent layer thicknesses and tried-and-tested production sequences.
A manufacturer’s expertise will also help to make sure the installation of the modular wall panels runs smoothly on site. Bespoke method statements can be developed providing guidance on the most effective and efficient process for applying the EWI or RSC system.
Thanks to ongoing research and development, specialist manufacturers have developed unique products designed to further increase productivity for those responsible for off-site prefabricated construction. These include adhesives and base coats which differ from standard products used on site as they dry much quicker helping to drive efficiency during the production process.
A further benefit is that these products can be delivered to factories in bulk quantities using silos with spray machines. These enable up to 1,000 kg of the adhesive and base coat to be directly sprayed onto the modular panels. Productivity is significantly enhanced using this equipment. Factory operatives don’t have to spend time opening numerous buckets and preparing the product by mixing it with water. With no buckets to be disposed of, this also means less waste.
Reducing environmental impact
As the need to reduce carbon emissions during construction intensifies, manufacturers are supporting their modular partners with environmentally-friendly products and processes. The StoVentec board for example is made from 96% recycled content, and our German headquarters are completely CO2 neutral. Featuring solar panels and running on hydroelectric power, 100 per cent of the electricity it purchases is certified green electricity.
With the potential to deliver a significant proportion of new homes, off-site manufacturing will continue to grow. Specialist manufacturers are ideally placed to respond through collaboration, innovative products and technical expertise. As a result, modular developers and contractors can benefit from tried and tested façade solutions as well as more streamlined production processes.