04 March 2017


A specification is a key contract document, typically produced during the technical design stage of a project. It is issued as part of the tender documentation and used throughout the subsequent timeline of the project. The content of a typical specification is traditionally a description of systems and products on a project and how these systems and products should be installed, finished and tested. This specification provides detailed technical information that accompanies what is visually represented in drawings or models. When preparing a well-written specification, there are a number of challenges. Three common problems are listed below:

1. Leaving the task of specification writing to be the final job of the technical design.

Too often stories are told of specifications that are written on the Friday afternoon (or even over the weekend) to complete the tender package. Designers are often given challenging deadlines for projects and as a consequence, writing the specification may be the task that gets pushed back.

2. Not recognising the need for a different approach to specification where contractors have design responsibility.

Design responsibility does not always fall to the designer directly employed by the client: many designers will work on projects where the description of the types of products is not their responsibility.

On these projects, the client’s designers must describe the required overall performance of these systems and leave the system and product choices to the design team employed by the Contractor.

3. A lack of communication and collaboration across the design team.

With modern technologies, many design teams are now collaborating by sharing models so that the spatial design of the architecture, structural and building service engineering is coordinated. However, it is not always the case that the same level of information-sharing takes place across the different disciplines with respect to specification responsibility and decision-making. This is especially true when considering the first two points – if specification writing is taking place late in the workflow and there is not sufficient clarity on responsibilities, then this can lead to confusion on the project

Addressing these challenges

It is worth considering how the above challenges can be addressed. The need for early collaboration around specification decisions and proper planning can go a long way towards making this process a lot smoother.

The RIBA Plan of Work provides a well-respected, standardised structure for documenting design responsibilities and deliverables. This structure also allows design intent to be documented early on so that architects, engineers and the wider team can start to transition from the briefing stage to the stage where technical design starts to develop.

For example, early on in a project there can be an understanding over whether curtain walling is required. The client’s requirements may be captured and the designer responsible may note whether, contractually, their responsibility will be for a full or performance specification. This may be documented at an early stage prior to any technical decision over whether the curtain walling is a stick or a unitized system. The same principles may be applied to the engineering work. For example, responsibilities for the heating system may be determined, and early discussions can take place which will inform the space requirements for potential plant rooms and the heat emitter requirements that may influence the interior design.

The plan of work should be produced collaboratively, and it should be updated at each stage of the project as more decisions are made. Too often on projects information is communicated but not documented, or it is documented in emails which are then not recorded properly.   If this process is followed then specification writing becomes a much easier task, and also one where the risk of incorrect decision-making has been greatly reduced. The information will have grown from the initial brief, structure will have been applied and responsibilities will be clear.   An industry-standard process such as this can be of great value, particularly when a project team comes together for the first time. When a team works together on a number of projects, or when a client procures many similar buildings, then this process can be greatly simplified.

With modern technologies, many design teams are now collaborating by sharing models so that the spatial design of the architecture, structural and building service engineering is coordinated
Producing a collaborative plan of work.

Case study

A case study was featured on theNBS.com website last year featuring Manchester City Council.

This detailed how the council were developing a standardised plan of work that detailed responsibilities and lessons learnt from previous projects to be used on a number of upcoming school projects.

Alistair Burns, Design Manager with the Capital Programmes and Property Team for the Council, has over 20 years’ experience working on schools projects and coordinated this initiative.

Alistair commented: “The Council’s Capital Programmes and Property Team wanted to have a template in place that captured the knowledge of the department and the years of experience and lessons learnt from previous projects. This would put the organisation in a strong position to have clarity on client information requirements on projects. In developing well-structured digital information the team at Manchester believe better project outcomes would be guaranteed and, in using the Digital Plan of Work across all stages, data flow would be significantly improved.”

Figure 1 shows the standardised plan of work for Manchester schools. It can be seen that the lessons learnt from previous projects are documented against the high-level technical deliverable. Responsibility is clearly defined against a role; the company undertaking this role is then to be determined on each individual upcoming project as that specific team is assembled.

Specification writing is a complex skill, but by giving it sufficient consideration early on in a project then the task of specification can be greatly simplified.

In summary:

  1. Discuss specification responsibilities at an early stage and document these in a standardised plan of work structure;
  2. Use a master specification system that allows both performance and prescriptive specification; and
  3. Collaborate across the project team so that the specification’s intention is clear and decision-making is facilitated.
Shows that it is possible to develop this information as the project develops. In this example, following the concept design stage, the architect has determined that fully-framed cubicles and privacy screen systems are required.
Based on the project’s requirements and the procurement method selected, these  systems can be specified by performance or prescriptively by the products that they contain.

In the first example, a performance specification is being developed that sets out the constraints  for the design work to be completed by the Contractor.
In the second example, a full specification, each product that makes up the system is fully specified.


A list of free-to-use and subscription solutions that support the principles covered in this article is below:

  • A free-to-download set of tasks and a standardised responsibility matrix is available in Microsoft Excel format at the RIBA Plan of Work website: www.ribaplanofwork.com/toolbox.aspx
  • This same content is available in a free-to-use online collaborative environment within the NBS BIM Toolkit: toolkit.theNBS.com
  • For those writing performance and full building and landscape specifications, NBS Create is the premium specification solution: www.theNBS.com/create

This article is taken from the NBS Specification Report 2017. Find out more and download the full free report including comprehensive analysis of our survey results.