Near zero energy through integrated design
EU research shows that collaboration in the early design phase of projects is key to successful delivery
Report from – Andrew Sutton
The basics of what most consider ‘sustainable design' have migrated from the fringe to the mainstream of the UK construction industry in the past 20 years. Post occupancy evaluation, embodied energy, lifecycle analysis and designing for deconstruction are all receiving more time, effort and (in some cases) funding by the more enlightened clients, designers and contractors.
Among the complex and overlapping drivers for this progression is the EU’s Near Zero Energy Buildings Directive (nZEB), which is due to be implemented by member states from 2020. In effect, this requires buildings to achieve very low energy demands via both fabric and on-site generation, although to do this in a ‘cost optimal’ fashion; the precise meaning of that is still something that is exercising the UK Government, although it is unlikely to mean ‘cheapest capital price’.
Progress for sustainable design in the next 10 years will therefore be strained by this ‘cost optimal’ sieve as the industry struggles to find ways to achieve economically viable ways of delivering near zero energy buildings within whatever parameters UK government defines. The search is therefore on for methods to improve the performance of buildings without increasing their overall cost.
Collaboration or how to achieve nZEB more cheaply
Research in the UK and throughout Europe has shown that one such method to enhance performance without increasing overall costs can be achieved through recently-clarified advancements in collaborative working and partnering. The essence of collaborative working is to reduce barriers between individual components of the construction team, thereby improving communications, reducing conflicts and, hopefully, improving outcomes. For the UK, partnering and collaborative working is not ground-breaking; and while in the private sector the principles sometimes haven’t made it out of the pages of the consultants’ contracts, many in public sector construction have made genuine steps towards more collaborative working, and partnering contracts have seen an increase in usage.
Taking collaboration to the next level
Integrated design (ID) is an advance on the principles of collaborative working and partnering. Research between 11 EU partners, including BRE for the UK, has demonstrated that a significant part of the challenge in delivering near zero energy buildings in practice is ensuring that the finished building is the best low energy match for the requirements of that building’s occupant: Perverse as it sounds, this frequently isn’t the case, and many of the causes for this difference can be traced to the early stages in a project’s development, rather than construction issues on site. Building on the basis of an openly interacting construction team, ID aims to address problems around these earliest stages of design and construction.
The first aspect of an ID approach helps to improve the Client Brief. Currently, these can comprise anything from a simple building size to exhaustive prescriptive details, with the tendency being towards shorter documents and a reliance on relevant industry best practices or standards (such as the British Council for Offices guidance). Once written, the Client Brief is enshrined in contractual obligations and used as the basis for the design development.
ID calls for greater interaction between the Client Brief and the project’s core design team, who should be appointed at RIBA Stage 1. The core team should include at least the architect and structural and services engineers, alongside the client. It is preferable to include end-users, building operators and relevant specialisms in this core team too; for auditoria, for example, acoustic consultants should be in the core team. One member of the core team, usually the services engineer, should have energy modelling capabilities suitable for early concept models.
Ensuring the Client Brief works
The first goal of the ID approach is to tease out from the original version of the Brief the specific project requirements, and filter any unnecessary restriction, specificity or industry standards that accidentally restrict or constrain solutions. Conversely, ID also sets out to ensure that where the client does have identifiable requirements, these are clear and measurably embedded. To the UK construction industry, this will be a recognisable goal; it is often cited that any successful building requires “a good client” or “a good brief” – ID effectively pushes the client to use their design team’s expertise to assist in creating “a good brief”.
How much input is required will, of course, vary from project to project. For large end-user organisations, some months investigating the business operational processes are likely to deliver benefits for the effectiveness of the end result, for smaller developments or those without known end users, a few weeks of review within the core team and client may flush out the most significant ‘unintended consequences’ in the original brief and set the goals for the project.
The concept stage
Having politely rewritten the client’s brief so the client gets what they need, not what they asked for, the core design team are then challenged in the ID process to think both analytically and creatively. Here the challenge is to work collaboratively across a series of concept designs that should be markedly different in their design approaches.
Each of the concepts is developed through a combination of workshops and design work by core team partners to form a basic ‘massing’ model that appears to satisfy the requirements of the revised Brief. These early concepts should then have basic energy modelling undertaken to estimate their performance. The outputs of the energy modelling should then form part of the analysis of each scheme undertaken by the client and core team in a workshop, with each scheme being critiqued on how they deliver the client’s requirements, and how energy intensive they are in doing so.
The results from the first analysis can then be fed into further rounds of development for one or more of the schemes, and the collaborative processes repeated to provide new concept designs for analysis. The intent is for the design process to throw open a wide net but rationalise this as an optimum solution that considers operational energy (although ID doesn’t prescribe that the lowest energy scheme should be considered the best; the final choice remains the prerogative of the (now informed) client.
Implementing good construction practice
Things become a little more prosaic once the preferred scheme concept design has been selected. Collaboration between the core team should be maintained, of course, and new team members inducted to understand the principles underlying the scheme and Client Brief (something frequently not given sufficient time). Similarly, key Client Brief goals should be embedded in any construction contracts and monitored for delivery through both the detailed design and construction processes – ideally also through the post completion occupation as well. However, putting aside the possible lack of emphasis on good collaboration, much of the remainder of the ID process is simply implementing good UK construction practices; establishing and monitoring against key targets through the design, Partnering ‘Pain/Gain’ contracts, Soft Landing provisions and the like.
ID therefore provides a semi-structured method of tackling the challenges of the earliest design decisions for a client, and in doing so aims to ensure that informed decisions are made over both the content of the Brief and the choice of the early concept design. This enables the client to understand the consequences of their decisions, especially in terms of energy, and so can make informed decisions about their priorities.
Andrew Sutton (RIBA) is Associate Director, BRE South West and also sits on the Steering Group of Wales Low/Zero Carbon Hub.
The research carried out by BRE and its partners was within the MaTrID project part funded by the Intelligent Energy Europe. Further information about the project can be found on the BRE website and also the EU project website.