Uniclass 2012 – classification is not just for geeks!


As a young architect in the 90’s, during the depths of the last recession, I worked for a year as a specialist specification writer in an architect’s practice. I was using NBS on a 486 PC with 3½ inch floppy discs! I soon learnt the difference between my E20 and Z10.

I’ve always been a fan of brickwork, particularly traditionally built, hand made, so F10 (Brickwork and Blockwork) probably is one of my most favourite NBS sections. (If you can actually admit to having a favourite section of a specification).

All change

However change is coming. The Common Arrangement of Work Sections from which we get E10, 20 and my F10, is all going to change. For those that love CI/SfB, the way building products are classified is also going to change. Uniclass, the overarching classification system that we use in the UK that ties all this together, is also changing.

So why change? Do we have to? Why change now? Why should we? Will it affect me, and my business? What if we don’t want to change? Think of the cost, the effort, the pain!

And anyway I love my F10!


Unfortunately, whilst BIM (Building Information Modelling) has many positive attributes and benefits, in terms of pure information management it is a harsh mistress. To be effective it needs absolute consistency of data, information and classification. Libraries of data are required which could contain products, elements, or intelligent objects with attached procurement or maintenance information, costing or programming data for instance. Rigorous classification is required to enable data to be used seamlessly and efficiently across the industry, from project to project, and business to business, up and down the supply chain – we need a reliable framework within which to work.

We’re rapidly moving into a world of data management over the whole lifecycle of a project or a built asset, with information being managed from project inception through to design, procurement, the construction stages and then on into the asset’s operational life, leading to eventual refurbishment, alteration, demolition and recycling.

End of the road

CI/SfB, CAWS and Uniclass in their current format have served their purpose in getting us here but their journey is now ended, as they can take us no further on the BIM road of integration and collaboration.

We need information systems that can handle all the data that we will use over the entire lifecycle as well as coping with the Levels of Detail in model development at the varying stages of design as it progresses.

Sarah Delany (CPI and NBS), John Gelder (NBS) and Stuart Chalmers (RIBA) recently gave a seminar on the background and proposed changes to Uniclass. At times it reminded me of an episode of the “Big Bang Theory” – rather than discussing particle physics we were treated to a discussion on the minutiae of data classification by some of the leading UK experts. By contrast I’m no expert here, but I do understand something about data management, in that the way data is classified and stored away for easy retrieval is vital to achieving working efficiency. So whilst you may well ask “ That’s all very interesting (or not), what’s Uniclass got to do with me?” The answer could be “More than you think!”

Uniclass 1997

CAWS (Common Arrangement of Work Sections) has been in use for 25 years. The current Uniclass from 1997, and CI/SfB from 1976. CAWS has been taken up by NBS, SMM7 and the NES. SfB was found to have limitations within a digital environment – its’ combination of letters, numbers and brackets makes life difficult.

The Uniclass of 1997 was anything but unified. It is a collection of disparate tables that have varied coding, some numeric, some alpha-numeric, with varying depth of detail and granularity (classification of projects, elements, objects, components), and as a consequence mapping correlation across tables is not possible – inconsistent and not unified! Uniclass 1997 also contains various legacy systems such as the RIBA Plan of Work, the London Classification of Business Studies, CI/SfB (which is now defunct as it hasn’t been updated as a system since the late 90’s), CAWS, CESMM3, CIB Master List and the UDC. There are many more inconsistencies at several levels in detail but space limits their discussion here. CAWS in itself is creaking as new sections are now added out of sequence – room for expansion is critical in any information system.

Uniclass 2012

The new Uniclass will have the following properties:

  • To fit within ISO 12006-2 which is the overarching European standard, which is also currently being revised (John Gelder is the UK expert for this)
  • To be a dynamic classification system so that it can grow and develop as our information needs change
  • All Tables will cover architecture (buildings and landscape), and civil and process engineering
  • The work by NBS will only develop the architecture & landscape components of the Tables, but leaving room for civil and process engineering, which are to be developed by others (via CPI)
  • All Tables will use numeric coding below level 1 – the familiar alphanumeric CAWS codes (e.g. H45) must go
  • Coding for level 1 (Tables) will be revisited, but may be numerical also, e.g. using ISO codes
  • All level codes in all Tables will be double-digit, from 00 to 99 potentially
  • Decimalization won’t be used (though users might apply it, e.g. in project specifications)
  • Tables will be sequenced to reflect the project timeline, as far as this is appropriate
    • –Large-scale objects precede small-scale objects
    • –Design precedes construction
    • All Tables will have four levels, where possible, and five levels otherwise. The four levels would be:
      • –Table, e.g. 25
      • –Group, e.g. 30
      • –Subgroup, e.g. 65
      • –Object (product, space, element etc), e.g. 88.
      • An object code might then be 25/30-65-88, for example
      • The coding system allows sufficient space for foreseeable future proofing and expansion

Updating CAWS

The principle drivers for change for updating CAWS are:

To achieve one, rather than multiple, classification system for:

–All sectors

• Architecture & landscape

• Civil engineering

• Process engineering

–All forms of procurement

• Build only – systems corresponding to trades (loosely)

• Design-build – high-level objects & systems needed

• Design-build-operate – high-level objects, systems and soft FM needed

–To cover the complete project timeline

The overall concept of the new CAWS is:

• Three levels: 21 Groups each of up to 20 Subgroups each of maybe 20 Sections

–8,400 Sections maximum

–1,145 identified in current draft – plenty of room for expansion!

• Systems: Most Groups

–Suits design-build procurement – services side already systems-based

–Systems correlate to trades

• Products: All located in product supermarkets


CPI has a commission for Easter 2012 to provide:

• Unified Tables – first tranche

–Work sections – now online for comment

• Work section structure – now online for comment

–Facilities – by activity

–Construction entities (buildings etc) – by activity

–Activities – by activity

–Spaces – by activity

–Elements – in draft – needed for 3D CAD

–Systems – in draft with NBS Create systems

–Products – in draft with NBS Create products

–Phases – in draft – CPI report on UK plans of work (unpublished)


NBS Create

–Services library launched November 2011

–Architecture etc libraries due March 2012

• NBS Create is a BIM-ready specification tool

• Other tools will follow in this series, serving the entire project timeline from inception to demolition, e.g. for briefing & FM


This has been a very brief tour of the reasons why Uniclass needs to be updated and also some of the ideas for the 2012 version.

We need a classification system that is fit for the digital age and as we all know life has changed so much in the last few years, let alone the 25 years since the original CI/SfB manual was brought out in the UK. It is long overdue for a major revision.

For those of us that know and love Common Arrangement now, there will be changes but I imagine there will be guides, seminars, courses and online tools to help us on our way. Unfortunately we are at one of those points on the journey where change is inevitable, it’s just a question of “to what?”

This change will affect most of us to some extent: the designer assigning attributes to elements and components in a model; an estimator taking off quantities and using Work Section references, ranging to a supplier or builder looking up products in a catalogue, and so on.

It reminds me of those times you realise that the supermarket has moved your favorite items to another aisle – it’s still there, just in a different place!

Uniclass 2012 offers us a system for BIM and beyond, with room for expansion and the opportunity to evolve and develop it on a dynamic basis as a classification system well into the future.

If you want to know more detail then I suggest you take a look at the CPI Website where you can find further details on the current consultation on Uniclass –


You will find the proposed updated tables and also the presentations from the recent seminars.

Also check out the NBS – National Building Specification website


This is your chance to have a say, as it will be no use complaining when Uniclass 2012 comes on line, and you decide you don’t like it. “Speak now or forever hold your peace!”

And finally for this blog….

Classification isn’t just for geeks and nerds – it affects everyone in the industry, whatever role you have, whatever you do, wherever you sit round the table and whatever part you play in the design and construction process…..the revisions to Uniclass are important to us all and perhaps , (dare I say it) interest in the new Uniclass could be the new sexy!!

Sheldon Cooper eat your heart out!



One thought on “Uniclass 2012 – classification is not just for geeks!

  1. It would be nice if the discussion on coding also reaches the offices of the small contractors en professionals in the building industry. In my experience is a combination of the NBN B06-003 (investment costs), NEN2634 (to be used in all the design steps), tabel 1 of the BB-SfB Plus (which includes renovation), STABU (for the materials to be used), tabel 4 – column 1 of BB-SfB, NBN B06-004 (exploitation) and definitions of the dutch “Bouwbesluit” work really well in daily practice. It took me years of studying and trying it into daily practice but now the system has good foundations with three entrances: one for project development, one for design and one for construction. Because forget to put everything you need into one table. You need to convert.


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