whg, Birmingham City University, Energy Systems Catapult, Northmill Associates and Hadley Group have a shared vision that people should live in safe, sustainable, and affordable homes. These partners brought their experience and expertise together to redevelop brownfield sites in the Midlands and put Design for Manufacture and Assembly (DfMA) to the test.

whg has 8,000 people waiting for social housing. House building is struggling with wasteful processes that impact programme costs and delivery times. Up until recently, there has been a lack of evidence for the benefits of modern methods of construction (MMC) particularly when applied to social housing. All this has meant costs have gone up, productivity has gone down and the industry is failing to meet market demand.

A shift in focus to 'life-time homes' and placing long-term value over low-cost construction will mean, quite simply, that homes will be built in a better way. A more innovative, collaborative approach to the design, manufacture and assembly of new homes will lead to a greater number of environmentally-friendly homes. This will mean more people can live in safe, sustainable, affordable homes. Not only that, but the repair and maintenance of these homes will be cost-efficient for the provider and of good quality to the resident.

Evidence was showing that modular homes built using modern methods of construction (MMC) are the same quality as traditional builds but quicker to put up, quicker to install and more energy efficient. Driven by its Development Strategy 2020-24 which sets out plans to build or acquire 2,200 new homes across the West Midlands region, whg saw an opportunity to be pioneers in this area. And so they set out to trial modular Design for Manufacture and Assembly (DfMA) houses on some of the borough's unused sites.

whg and its collaborative of experts secured government, industry and academic backing to test a proof of concept using Design for Manufacture and Assembly (DfMA). A Knowledge-Based Engineering tool (KBE) was designed by Birmingham City University alongside the prototype, to ensure the most efficient approaches are used at every stage. The prototype and the analysis that followed showed a hugely positive impact in a number of challenges that the industry faces today. It demonstrated a reduction in build and life-cycle costs thanks to standardised processes and components; a significant reduction in design and construction time; and reductions in household energy consumption and carbon emissions.

It's a challenge to build social housing with value in mind. Often these buildings have to be constructed at pace and with an effort to keep costs low and these short terms constraints don't always lead to buildings for the long-term. This short-term view and need to minimise costs has meant that there has been a reticence to embrace new innovations that could require investment in new skills or technology, discouraging pioneers and preventing development in this important area of housebuilding.

Design for Manufacture and Assembly (DfMA) 'modular' houses are essentially built in a factory before being transported to their final destination to be installed. The team adopted a scalable approach for the delivery of customisable DfMA houses. It can accommodate stick, panelised, hybrid and volumetric approach to meet with site requirements. This is a uniquely flexible system. To optimise the installation of the prototype, the collaborative developed a Knowledge-Based Engineering tool (KBE) that would estimate where the greatest emissions and costs come from, across both the life cycle of the build and home once in use, and adjust the design to minimise investment and carbon footprint. The KBE tool provided information on the aspects of DfMA that added value and those that didn't. It meant the build teams could select options that focus on quality and value, rather than cheapness – ultimately building better, faster and greener. It also allowed them to eliminate non-essential areas where possible. As the build progressed, the KBE monitored the quality of the home installation and fed information back to a central database. The KBE tool can be used throughout the supply chain – from architect through to contractor. It can be used on previous contracts too, to demonstrate the value that could have been delivered and prove the quality of this approach - creating certainty and confidence for the supply chain and contractors, and help set evidence-based benchmarks for DfMA houses.

This project drew on Building Information Modelling software (BIM) so that the design could be continually iterated, and take into account any changes or updates as the prototype is developed. It allowed the project partners to consider how and where aspects of DfMA could be automated or benefit from robotics. The project also pioneered the application of the Home Energy Dynamic (HED) model - a modelling tool to assess energy consumption - developed by the Energy Systems Catapult. The demonstrator has proven that household energy consumption is reduced by 80% when using the full toolkit developed by the team.

The collaborative is passionate about helping the sector understand DfMA and become more familiar with modern methods of construction and how it can support life-time value rather than just the lowest cost. Time and money was invested upfront to understand the best way to build quality, sustainable modular homes on brownfield sites, as well identify efficient Repair & Maintenance (R&M) processes that would deliver a longer term return on the build for the customer and the end user. After the successful trial, the programme of the homes is now being rolled out more widely. The Small Sites Strategic Group (SSSG) at whg has identified over 200 existing, mainly disused, garage sites across the Midlands that could be developed using DfMA, offering a potential pipeline of approximately 350 new homes. The collaborative is also now using the learnings from this demonstrator to educate the supply chain and influence policy makers to commit to building offsite homes at scale with a focus on value and impact. They are working with the West Midlands Combined Authority to commit to procuring homes built using modern methods of construction, and shifting focus from cheap builds to life-time homes. Finally, Birmingham City University (BCU) developed the KBE guided by their 'five principles of lean' (https://bit.ly/2Su9Eg5) to ensure houses are built with increasing productivity and reducing wasteful processes. BCU has developed academic thinking around automated production for offsite housing and classifying waste according to 'value', 'non-value add' and 'non value add but unavoidable' steps in the offsite process. BCU is is preparing a journal paper to share the results of the study and it is this mixture of academia, construction and digital manufacture which made this collaborative so successful.

whg and Hadley Group worked with Birmingham City University to developed the KBE tool that would inform the Design for Manufacture and Assembly (DfMA) demonstrator project. The consortium also included Energy Systems Catapult, Northmill Associates, and QM Systems. Homes England has since invited whg and Hadley Group to sit on the expert panel of the West Midlands Combined Authority AMC task force, alongside the Government's MMC champion Mark Farmer. Hadley Group is also working on TUPROOFS, which is investigating how to make retrofit roof panes more efficient at generating power by incorporating solar power and a water-heating process underneath the panel. The consortium is comprised of Advanced Construction Technologies, BIPVco, Midlands High Growth, West Rogers Ltd. and Hadley Group. If successful, it is anticipated that more than 30,000 houses in the U.K. will be retrofitted with the panels, providing thousands of families around the country with greener energy, eliminating fuel poverty and creating thousands of new jobs.

• Birmingham City University
• Energy Systems Catapult
• Hadley Group
• Homes England
• Northmill Associates
• QM Systems
• whg

Thanks to Transforming Construction and Innovate UK's investment and industry links, the collaborative was able to increase its knowledge and expertise, bring together a team of partners with complimentary skills, share best practice in order to scale up, create a new supply chain, and ultimately transform the way homes are built in the Midlands. The backing of UKRI allowed the team to think big and make it part of its business as usual.

With strong support from the sector and the government for Design for Manufacture and Assembly (DfMA), this demonstrator project has now provided the proof of concept that construction companies, local authorities and housing associations need to further adopt it in the future. And with a Development Strategy that sets out plans to build or acquire 2,200 new homes across the West Midlands region, whg has shown that investment in modern methods of construction no longer need to be a nice to have, but can be an essential part of continuous improvement - and that DfMA leads to more efficient and productive builds. If we build for a lifetime like this, there will be greater supply of sustainable, affordable houses that in turn offer a better quality of life for the householder.

whg has a waiting list of 8,000 people hoping to be offered a home with them. Applying Design for Manufacture and Assembly (DfMA) at scale, now that it has been tested, could dramatically increase access to sustainable, affordable quality houses and in turn improve householders' quality of life. DfMA will also create much safer working environments compared to traditional production onsite, and the introduction of new platform design process and technology will create new roles and skills for the future workforce. The KBE tool will help create houses which could tenants approximately £200 per year on energy bills. This is circa £63,000 over 60-year building life per house unit. Hadley Group are working with charity Spacious Places to upskill people building homes offsite, using MMC. This engagement to employment model is being trialed in Burnley throughout 2021.

Collaboration up and down the supply chain has been key to the success of this project and the partners have successfully pooled their knowledge, expertise and experience to create a powerful proof of concept. Design for Manufacture and Assembly (DfMA) has mean that site identification, planning and management have been more efficient, and the design and build has been more consistent and accurate - focusing on those elements that add greatest value, not just lowest cost. The automated manufacture and assembly processes have increased productivity, improved safety, and reduced cost, time and emissions. Ultimately, the project enables the sector to use these modern methods of construction in a way replicated easily, but also adjusted to particular needs - a repeatable and customisable tool.

With 8,000 people waiting for a home, whg had tough targets to meet, at pace. Its Development Strategy 2020-24 sets out plans to build or acquire 2,200 new homes across the West Midlands region After identifying 200 existing brownfield sites that were ready to be built on, whg and Hadley Group estimated that Design for Manufacture and Assembly (DfMA) would allow them to build at least 350 new homes by 2022. The proof of concept then gave whg clear indications that homes built this way would show at least a 33% reduction in life-cycle costs, a 10% reduction in build costs, and a 50% reduction in design and construction time. The automation approach for panels has the potential to produce more than 24,000 panels a year, enough for >600 DfMA houses. Not only that, DfMA houses could reduce household energy consumption by at least 30% and carbon emissions by 50%, ultimately creating greater access to affordable, sustainable homes.

Collaboration
The consortium on this project proved the value of a culture of sharing best practice. By working together, whg and partners gained knowledge, pooled expertise, built networks and created a new supply chain knowledge-based tool to drive efficiencies and improve outcomes. This team offered a diverse mix of knowledge from universities, to local authorities, to steel manufacturers and energy efficiency experts. whg and Hadley Group are now taking these learnings into the West Midlands Combined Authority AMC task force.

Cost
Homes built using modular designs and pre-assembled frameworks are quicker to assemble and install, and rely on less materials and labour, which both have the potential to reduce cost. The new design also supports cost savings over the lifetime of the home. whg and Hadley Group believes that the design will require less repair & maintenance over the lifespan of the house, and currently estimate a possible 33% reduction in life-cycle costs. This is being tracked as the homes become occupied.

Diversity
Birmingham City University's PhD student, Kudirat Ayinla is now applying her knowledge of lean concepts gained from this project to identify and evaluate the process wastes of two types of house production methods (i) the method used to build the prototype, offsite construction without automation and (ii) semi-automated method. The team at BCU together with Kudirat are looking to generalise the process of house production.

Emissions
The collaborative originally predicted a 30% reduction of household energy consumption and carbon emissions reduction of 50%. Energy Systems Catapult have now created a Home Energy Dynamic model which proves that household energy consumption is reduced by 86% when using the full toolkit developed by the team.

Investment
Hadley Group is investing £3 million in expanding their facilities based on the findings and outcomes of this project.

Productivity
According to the DfMA house assembly report prepared by QM systems, it takes about 8 minutes to assemble 1 panel frame, a sub-assembly unit of the DfMA house. The time is compared with the manual production time for the prototype DfMA house. The corresponding time required to produce 1 panel frame by a gang of 2 labours and a supervisor is 45 minutes. Thus, the production line speeds up the production of the panel sub-assembly for DfMA house by more than 5 times. With demand for social housing high (there are 8,000 people waiting for social housing in Walsall), DfMA should support more houses being built in less time and for less cost. This is an important metric that will continue to be tracked and measured.

Regional Balance
With a strong focus on social housing solutions in the Midlands, this project is already acting as a hub or role model for other areas in the region. To this end, Homes England has invited whg and Hadley Group to sit on the expert panel of the West Midlands Combined Authority AMC task force. The introduction of new platform design and technology is also likely to drive employment and skills opportunities in the area.

Safety
Design for Manufacture and Assembly (DfMA) supports a safer working environment compared to traditional production onsite, because much of the work is undertaken in a controlled factory environment, rather than varying construction sites. DfMA also allows for more testing in the factory which cannot always be done onsite.

Time
With so much of the manufacture and assembly being done on a factory production line, this new modular building technique has delivered a 50% reduction to the design and construction time. The use of the Knowledge-Based Engineering Tool (KBE) also showed a reduction in the time spent planning the project.

Trade Gap
This project has not only driven UK investment in UK homes, but has created the opportunity to expand into Middle East markets through the Hadley Group connections, positioning the UK as a pioneer in Design for Manufacture and Assembly (DfMA) when applied to social housing.

Whole-life Value
This project has whole-life value at its heart. It set out to test how modern methods of construction in social housing could create more sustainable, affordable homes, that in turn offers a better quality of life for the householder. The pilot sites have given whg and the collaborative evidence for more sustainable, safer and productive builds, and has created best practice that the Midlands, that the wider UK industry can learn from.

PBC Today 27th May 2020
Hadley Group case study
AMC Project Briefing / buildoffsite.com
UKRI Overview
Birmingham City Research Project case study
Energy Modelling of Modular DfMA Housing for Walsall Housing Group
Designing New Forms with Light Steel Frame
WSP BACKED SOLUTION OFFERS FLOODZONE DEVELOPMENT OPPORTUNITIES