How can product manufacturers support construction projects throughout the RIBA Plan of Work?

The RIBA Plan of Work is arguably the most common approach to describing the various stages of construction projects in the UK. The Plan of Work is a framework for architects, primarily; as it has evolved, however, it has become an industry-wide tool. As a framework for projects, the Plan of Work is designed to provide clarity and consistency of approach to the process of designing, specifying and constructing buildings.

The increasingly complex nature of construction projects is reflected in how the RIBA have updated the Plan of Work in recent years. Following its introduction in 1963, the Plan of Work did not receive its first significant update until 2013. Just seven years later, the RIBA updated again – this time reflecting advances in digital innovation and modern methods of construction.

Traditionally, information from construction product manufacturers would only have been introduced to the project from the middle stages of the Plan of Work, as a detailed design started to be developed. But the evolving complexity of construction – including the need to deliver building safety and performance, with a record of decisions made – often means it is beneficial to take on board specialist advice at an earlier stage.

Not all stages are relevant to all projects. Nevertheless, construction product manufacturers can provide valuable support to design professionals and specifiers throughout the RIBA Plan of Work stages. This blog post gives an overview of what that support might look like.

Plan of Work stages 0-2: strategic definition / preparation and briefing / concept design

Manufacturer involvement at stages 0 and 1 is very unlikely, since they broadly concern defining the project scope, establishing a project programme and creating a project brief.

Nevertheless, manufacturer engagement should be a key part of the early project, and stage 2 (concept design) is an ideal time for that to occur. The Designing Buildings Wiki explains how concept design is “generally considered to be the first true design stage” and includes the preparation of outline specifications.

Every stage of the Plan of Work features sustainability ‘checkpoints’ and the development of a sustainability strategy should be a key feature of the strategy and briefing stages. Concept design is the opportunity for those sustainability goals to begin influencing the shape of the project, including the desired outcomes in terms of building fabric performance and occupant wellbeing.

Once those goals are defined, understanding insulation solutions that could be employed can inform early design choices and avoid compromises being made once the project reaches site.

Plan of Work stages 3-4: spatial coordination / technical design

‘Spatial coordination’ replaced the name ‘Developed design’ for stage 3 of the Plan of Work. Even now, however, people are more likely to refer to it as ‘detailed design.’

Detailed design and technical design take a project through the key approval stages of a planning application and a building regulations application. The initial concept is more fully realised, taking on board input from other consultants such as structural engineers and building services engineers.

If the scale of the project did not warrant manufacturer involvement at stage 2, then this is certainly the time to take on board advice that affects the fundamental setting out of the building.

Planning applications do not require detailed information about proposed insulation materials and thicknesses. However, an application may stand more chance of success if a coherent sustainability strategy is set out, including a clear idea of building fabric measures that will be used.

And the choice of materials will influence fundamental spatial considerations like wall thicknesses, roof heights and overall building footprints/room areas.

“Any responsible manufacturer provides a wealth of information to assist in making crucial design and specification decisions,” said Rob Firman, Polyfoam XPS’s Technical and Specification Manager. “But there is no substitute for project-specific advice and we always encourage designers and specifiers to speak to us directly for technical information and guidance tailored to a project’s outcomes.”

Plan of Work stage 5: manufacturing and construction

Previously ‘Construction,’ the changed name of this stage reflects the increased adoption of modern methods of construction and manufactured solutions – of which insulation products may form a significant part.

In terms of an architect’s involvement, stage 5 is focused more on contract administration. The design is complete and a contractor should have possession of the site to carry out the works.

Of course, with different forms of procurement, specification work may still be undertaken while construction is in progress. And even if the architect’s involvement is reduced, contractors have questions about the products they are using.

Projects of all shapes and sizes encounter issues on site, and manufacturers have an essential role to play in supporting installers at this stage. Typical examples that the Polyfoam XPS technical helpdesk assists with include not enough floor depth to accommodate the insulation, and detailing issues with flat roof thresholds.

The key is to identify such issues as soon as they arise, and get in touch with us so we can contribute whatever support we are able as part of reaching a solution.

Plan of Work stages 6-7: handover / use

Traditionally, the construction industry has a poor track record when it comes to completed buildings. In-use monitoring to check that anticipated performance targets are met is uncommon. Design professionals and specifiers rarely seek feedback on what worked and what didn’t, in order to inform future projects.

There are signs of that changing, especially where quality control measures are in place during construction, or where voluntary standards require evidence of in-use performance to achieve certification. Whole life carbon assessments are changing how building design and specification is thought about, introducing concepts like designing for disassembly and the circular economy.

From a construction product perspective, thermal insulation is the very definition of a ‘fit and forget’ product. It is covered up within the fabric of the building and, when installed correctly, delivers its performance for the life of that building.

However, that doesn’t mean our involvement as a manufacturer ends at the installation stage. We are here to answer questions about in-use performance that may relate to our insulation.

And, as a building nears the end of its useful life, consideration might turn to how insulation products could support the adaptable use of a building, or be removed and dealt with as part of any demolition. Again, we are here to support you with those ideas.

What to do next

A key takeaway from this post is that engagement is as crucial at the end of a project as it is in the early stages. A responsible and transparent manufacturer, in any product sector, welcomes conversations at any time.

But engagement doesn’t have to be exclusively within the project environment and the Plan of Work stages. Conversations outside the project environment, with no specific goal attached, can happen in a variety of ways, including at trade shows like Futurebuild, or during CPD sessions.

These conversations might seem like a luxury, but they can be a crucial first piece of a jigsaw that is only added to weeks, months or years later when the manufacturer gets an opportunity to provide crucial support to a project where their solution is integral.

To start your conversation with Polyfoam XPS today, contact us, subscribe to our email newsletter and connect with us on LinkedIn, and gain useful insight into extruded polystyrene that could support your future projects.

April 2026 note: this blog post is based on content written for the first edition of The Polyfoam Orange Book of XPS Insulation, our comprehensive guide to extruded polystyrene (XPS) published in March 2026. Written for designers, specifiers and contractors, you can learn more about the book, including how to request a copy, here.