Common Arrangement of Work Sections
The Common Arrangement of Work Sections (CAWS) was developed by the Construction Project Information Committee (CPIC), a pan-industry organisation with representatives from key industry institutes.
It was developed as a result of research demonstrating that the quality of construction information was a very significant determinant of the quality of construction. It was recognised that standardisation of the way production information was created and classified could help improve quality, and that the commonly used CISfb classification was not sufficiently comprehensive to achieve this.
CAWS established a consistent arrangement for specifications and bills of quantities. It was first published in 1987 and was updated by CPIC in 1998 to align it with the Unified Classification for the Construction Industry (Uniclass). In 2005 nbs submitted to CPIC, modifications to the services sections of CAWS for consideration and following 5 years of consultation these changes were accepted.
CAWS is the categorisation of work that is used for the National Building Specification (NBS – which before 1987 followed the CISfB structure), National Engineering Specification (NES), the Standard Method of Measurement, currently in its 7th Edition (SMM7) and a number of industry pricing books such as Spons, Laxtons and Wessex.
CAWS has since been incorporated into Table J of Uniclass, which was also developed by CPIC. Uniclass is a classification system for organising library materials, product literature and project information.
In 2011, the CPIC used the nbs proposals for re-classification of the work sections in CAWS and Uniclass Table J as the basis of a consultation process for revising Uniclass. This development of Uniclass as a whole is considered to better accommodate civil engineering and process engineering alongside architecture and landscape, it also better enables the description of systems in performance terms, and is more suited to accommodating facilities management.
The main categories are:
- A - Preliminaries
- B - Complete buildings / structures / units
- C - Demolition / Alteration /Renovation
- D - Groundwork
- E - In situ concrete / Large precast concrete
- F - Masonry
- G - Structural / Carcassing metal / timber
- H - Cladding / Covering
- J - Waterproofing
- K - Linings / Sheathing / Dry partitioning
- L - Windows / Doors / Stairs
- M - Surface finishes
- N - Furniture / Equipment
- P - Building fabric sundries
- Q - Paving / Planting / Fencing / Site furniture
- R - Disposal Systems
- S - Piped supply systems
- T - Mechanical heating / Cooling / Refrigeration systems
- U - Ventilation / Air conditioning systems
- V - Electrical supply / power / lighting systems
- W - Communications / Security / Control systems
- X - Transport systems
- Y - General Engineering Services
- Z - Building fabric reference specification
Each section includes further sub-classification and offers detailed information and supplementary rules. For more information see: Common arrangement of work sections classification.
NB: SMM7 has been replaced by the New Rules of Measurement (NRM) which has moved away from CAWS, to adopt its own system of indexing. See New Rules of Measurement for more information.
[edit] Related articles on Designing Buildings
- Bills of quantities.
- BIM classification.
- CI/SfB.
- Classification, an introduction.
- Common arrangement of work sections classification.
- Comparison of SMM7 with NRM2.
- Construction Project Information Committee.
- Elemental cost plan.
- How to take off construction works.
- New Rules of Measurement.
- Preliminaries.
- Production information.
- Specifications.
- Spot items.
- Standard Method of Measurement (SMM7).
- Sundry items.
- Uniclass.
- Work section.
[edit] External references
- CPIC.
- NBS.
- NBS article on CAWS reclassification.
- NBS article on Co-ordinating CAWS and NRM.
Featured articles and news
Shortage of high-quality data threatening the AI boom
And other fundamental issues highlighted by the Open Data Institute.
Data centres top the list of growth opportunities
In robust, yet heterogenous world BACS market.
Increased funding for BSR announced
Within plans for next generation of new towns.
New Towns Taskforce interim policy statement
With initial reactions to the 6 month policy update.
Heritage, industry and slavery
Interpretation must tell the story accurately.
PM announces Building safety and fire move to MHCLG
Following recommendations of the Grenfell Inquiry report.
Conserving the ruins of a great Elizabethan country house.
BSRIA European air conditioning market update 2024
Highs, lows and discrepancy rates in the annual demand.
50 years celebrating the ECA Apprenticeship Awards
As SMEs say the 10 years of the Apprenticeship Levy has failed them.
Nominations sought for CIOB awards
Celebrating construction excellence in Ireland and Northern Ireland.
EPC consultation in context: NCM, SAP, SBEM and HEM
One week to respond to the consultation on reforms to the Energy Performance of Buildings framework.
CIAT Celebrates 60 years of Architectural Technology
Find out more #CIAT60 social media takeover.
The BPF urges Chancellor for additional BSR resources
To remove barriers and bottlenecks which delay projects.
Flexibility over requirements to boost apprentice numbers
English, maths and minimumun duration requirements reduced for a 10,000 gain.
A long term view on European heating markets
BSRIA HVAC 2032 Study.
Humidity resilience strategies for home design
Frequency of extreme humidity events is increasing.
National Apprenticeship Week 2025
Skills for life : 10-16 February