04 March 2017

The findings in the NBS Specification Report 2017 provide us with a good understanding when it comes to the industry's experience of specifications and future expectations. Clearly, specifications remain an important topic for many so, with that in mind, we asked four people working in the construction industry to share their experiences with us in more detail.

Our specifications panel

Stewart Lunniss
(Lerander-Design architecture + interiors)

Stewart is an architect with 20+ years experience working in private and public practice and client side for a developer, with experience of overseas projects for the Foreign & Commonwealth Office. Now setting up as a sole practitioner with interest in the diplomatic sector.

Mark Taylor
(Director, Allies and Morrison)

Mark is the director at Allies and Morrison responsible for technical quality, providing knowledge transfer, research and support on construction, sustainability, materials and  process. He has particular expertise in building envelope technology, holding a masters degree in facade engineering. He regularly  contributes to industry  through teaching, lecturing, and working on various industry committees and councils.
 David Wigglesworth
(Managing Director, SFS intec)

David has over 20 years’ experience working for leading manufacturers in the construction industry. This includes 14 years’ experience at Managing Director level, of which the last eight years were spent at global leading door-opening solution company ASSA ABLOY. In the latter two years, David defined and led their UK specification capabilities. David joined SFS intec in March 2016 as Managing Director with full P&L and operational responsibility for the UK Market Region, with a key focus on further strengthening relationships within the company’s broad customer base while identifying new market opportunities for mutual benefit.
Andy Jobling
(Technical Manager: Architect: Principal Designer (CDM),
Levitt Bernstein)

Andrew is an Architect of 30 years’ post-registration experience which covers various building types, including transport, commercial, industrial, neurological and mental health – and most recently affordable housing, theatres and arts projects. He also has experience of a range of construction methods and materials and procurement strategies.

Andrew holds a Technical Manager role within the practice, providing designated technical support, advice and assistance to the whole architectural staff. He also manages the Quality Management System and training needs of the practice, requiring him to keep up to date with current legislation, regulations,  products, materials and construction practice.

Responsibility for dissemination of feedback within the practice and development of office master specifications further reinforces his knowledge of construction best practice. 

Views from our specifications panel

Stewart Lunniss

Stewart Lunniss

Leander-Design architecture + interiors

My first exposure to NBS was at university – such an off-putting experience! It left me living in dread of the day that I would be asked to ‘write up the spec’ when in practice. A few years passed and the day came when I inherited a dormant project... the format seemed familiar, but where were the completed clauses? F40 & M60 missing? Yes, lots of blanks where my predecessors had skipped clauses or left numerous pages without editing: a situation I found all too familiar in other practices.

I did not set out to be the NBS ‘geek’ in practice but have found myself being the NBS ‘champion’ over the past 20 years, whether in practice or on the client side. I sought to deliver quality outcomes for clients and end-users alike, and to have a contract document which ensured that the contractor executed the project to recognisable and measurable standards.

I learnt early on that the best way to start writing up the project specification is to start early and fill in clauses as the design develops: anything to avoid that daunting cliff face with one month to go until tender issue – we have all been there.

For colleagues who dread specification writing, I often state that NBS acts as an ‘aide-mémoire’. On one of my early projects, the omission of door seals across 70 apartments was a costly variation for the client. Conversely, a contractor seeking a variation for additional profiled skirting was referred to the clause that stated ‘ogee profile’... such a relief for me as the architect and specifier.

Amusingly, one quantity surveyor considered NBS ‘top-heavy’ and discouraged a competitive tender return – my view is that any contractor not willing to review the specification is best avoided.

Technology, the internet and the user interface of NBS Building and Scheduler have evolved to make specification writing more pleasurable and a good way of keeping up to date with new products and standards. If there is one criticism, it is that there is too much information just a click away: a diversion from design

I learnt early on that the best way to start writing up the project specification is to start early and fill in clauses as the design develops.

Stewart Lunniss, Leander-Design architecture + interiors


Mark Taylor

Mark Taylor

Director, Allies and Morrison

Substitution is where a contractor constructs something different from that which is drawn or specified in the Employer’s Requirements information.

Products are the usual targets for substitution, but methods, build-ups and materials are commonly victims of change. This may not all be bad news as long as there are no changes to the visual requirements, the functional requirements or the performance requirements. As long as these three critical aspects of the Employer’s Requirements are met, there will be no change to the look, feel and workings of the item being substituted. Notice that requirements of the contract can’t be changed without a formal variation to the contract. There is a difference between requirements and the means of achieving those requirements. Substitution has its place within the means, but not in the requirements themselves, unless a variation is put in place.

Common reasons for substitution are as follows:

  1. Where a contractor may optimise their process in programme, cost or practicality, whilst still meeting the Employer’s Requirements. A design and build dry lining contractor may combine specified systems together for simplicity without affecting the Employer’s Requirements.
  2. Where the contractor uses a procurement framework and the specified item cannot be bought through their usual channels.
  3. If the information in the Employer’s Requirements is contradictory or erroneous.
  4. If a specified product or material is no longer available; an equivalent must be found.
  5. Sometimes changes made to the project by another part of the works triggers a need for a substitution.
  6. Where an item is outside the designing consultant’s domain of expertise, the specialist contractor would complete the design; but if the consultant has assumed something that cannot be built, an alternative must be found.

The definition of whether a substituted item is in accordance with the ERs depends upon the rules of equivalence stated in the tender documentation, including the specification. Again, if a substitution item is visually and functionally equal, and provides equal performance to the specified item, it would normally be equivalent. The original information must therefore communicate precisely both the requirements and the rules of substitution.

Substitution is where a contractor constructs something different from that which is drawn or specified in the Employer’s Requirements information.

Mark Taylor, Allies and Morrison


David WigglesworthDavid Wigglesworth

Managing Director, SFC Intec

Manufacturers need to support architects and designers more. Providing support to designers is not a problem for SFS intec: we’re happy to help.

From our perspective, we believe that education and a continual cycle of education for designers will help to improve the specification process. We offer a number of RIBA-accredited CPD seminars. But it’s also about how we continue to promote the relevance of specification clauses through NBS, ensuring the accuracy of those clauses and specifications, and how we evolve and embrace the development of Building Information Modelling. BIM will help support a more robust specification that will make it more difficult to substitute products, given the cycle of stages to achieve a federated model. It will help us to embed the specification, and therefore decision-makers will have to carefully consider the arguments for and the consequences of a product substitution. Subsequently, the value of cost savings on such a small percentage of the build value versus the risk of liability won’t make commercial sense.

SFS intec want to be seen as a specialist within our field and as a ‘design partner’ in the initial stages  of the design. It’s interesting to note  that in the NBS specification survey results, 70% of respondents agree  that the process works best when  manufacturers are involved at an early stage. We are keen to support the architects in their BIM journey, their  education, and in designing out their liability in terms of performance and  application. As a manufacturer, we have the global depth and breadth  of technical knowhow to understand the unique variables that may not  be obvious to the specifier, so why  not use those advantages to  mutual benefit?

Manufacturers need to support architects and designers more.

David Wigglesworth, SFS Intec


Andy JoblingAndy Jobling

Levitt Bernstein

Specification is becoming more complex, and those who specify have less opportunity to gain the skills required.

Vernacular architecture is an evolution of materials and details that are known to perform, and are familiar to designers and builders alike. Contemporary architecture uses new materials and highly engineered systems, and often uses familiar materials in novel ways where their applications are tested to their limits. This approach is coupled with procurement options, such as design and build, which actively discourage designers from attending site where they would gain a hands-on knowledge of how systems and components are assembled and installed. There is, therefore, a heavy reliance on the supply chain side to assist designers to achieve the necessary performance levels and their design intent.

Whilst manufacturers are aware that it is in their interests to ensure that their products are correctly specified and installed for the long-term sustainability of their businesses, the designer/specifier should nonetheless be critical of information that they are offered by them, and should be able to strengthen the requirements in the specifications they produce. As no individual can be an expert across all fields of the specification, there is a need for access to the accumulated knowledge and experience of the particular practice and the industry as a whole. Online information systems and company intranets are useful tools, but guidance at point-of-use is most effective. One of the strengths of NBS’ specification software is that it not only provides us with comprehensive guidance from their technical authors, but importantly it allows us to embed our own guidance, which is offered to the specifier when they need it without any searching on their part.

At Levitt Bernstein, we create opportunities for our specifiers to visit construction sites and completed buildings to evaluate and learn about the products and systems that they are specifying. However, whilst this builds their technical knowledge, there is a real need for some training that would assist them in putting together a robust specification. Benoy did float the idea of a specification-writing course with BRE a few years ago, but the recession intervened. Perhaps now is the time to revive it.

With BIM comes new opportunities. The specification is no longer just a tool for communicating and controlling the quality and durability of the building during construction, but now has an extended life as an asset management tool – and a very powerful one if linked to the spatial model through BIM. Not many clients have yet realised the longer term value that they have in the specification. In future, I think we will see the specification as an active document that evolves from the brief, is extended through the design stages, and is further updated during construction, before being handed over to the client to manage the asset. However, as construction remains a disparate industry with many players, there will need to be clear demarcation of design responsibilities along the lines that we are now seeing in the BIM Execution Plans. In future, the specification will be a key deliverable on all construction projects.

The specification is no longer just a tool for communicating and controlling the quality and durability of the building during construction, but now has an extended life as an asset management tool – and a very powerful one if linked to the spatial model through BIM.

Andy Jobling, Levitt Bernstein


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.