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  • PublisherCIBSE
  • Product CodeCCW
  • Number of pages34
  • Publication DateOct 2010
  • ISBN9781906846152

CCW Commissioning Code W: Water Distribution Systems


PDF Format







PDF Format






CCW Commissioning Code W: Water Distribution Systems

Commissioning of buildings and building services is vitally important to the safe and energy efficient operation of buildings but it is not always carried out — or carried out systematically. The effective operation of any water system is dependent on satisfactory circuit balancing and commissioning. This in turn requires adequate attention to commissioning requirements during the design of the system, and a clear specification of requirements.

CIBSE Commissioning Codes set out clearly and systematically the steps required to commission buildings and building services in a proper and timely manner. This key step in the life of the building enables the system to operate as it was designed to do, and, coupled with good maintenance practice, helps provide building occupiers with a safe, good quality, comfortable internal environment delivered energy efficiently.

This edition of Commissioning Code W is based on the 1994 edition. The revision reflects the introduction of requirements for commissioning into Part L of the Building Regulations. The opportunity has also been taken to reflect the growing awareness that many key decisions relating to the construction process are taken in the very early stages of a project. The Code therefore gives the strongest encouragement to designers and clients to consider commissioning and to seek suitably qualified specialist input at the earliest stages of a project.

CIBSE Commissioning Code W represents current standards of good commissioning practice presented in the form of recommendations and guidance which are generally accepted in the building services industry. The Code acknowledges that it may be applied in a variety of contractual frameworks. Users will need to ensure that the use of the Code is considered when contractual arrangements are being made, to ensure that the recommendations of the Code are not in conflict with those of the contract.

A full set of 7 CIBSE Commissioning Codes can be purchased in hard copy format here for A SPECIAL PRICE.


W0 Introduction
W0.1 Scope
W0.2 Purpose
W0.3 Summary of commissioning requirements
W0.4 The importance of commissioning
W0.5 Other guidance
W0.6 Definitions
W0.7 Specification
W0.8 Inspection
W0.9 Commissioning records
W0.10 Responsibility

W1 Safety issues
W1.1 Legislation
W1.2 Good practice

W2 Design for commissionability

W3 Specification issues

W4 Commissioning project management

W5 Pre-commissioning
W5.1 Objective
W5.2 State of the system
W5.3 Checks before filling
W5.4 System filling and venting
W5.5 System flushing and cleaning
W5.6 System checks
W5.7 Static completion records

W6 Setting pumps to work
W6.1 Pressurisation sets
W6.2 Checks before pump start
W6.3 Initial run
W6.4 Further venting
W6.5 Completion certification

W7 Balancing and regulating water flow rates
W7.1 Objective
W7.2 Flow rate measurement tolerances
W7.3 Basis of proportional balancing
W7.4 Pump shut-off head test
W7.5 Preliminary flow rate check
W7.6 Constant volume systems
W7.7 Variable volume systems
W7.8 Balancing by compensated method
W7.9 Regulation by temperature balance
W7.10 Commissioning certification

W8 Evaluation and witnessing of commissioned systems
W8.1 Objective
W8.2 Witnessing arrangements
W8.3 Duties of witnessing agent
W8.4 Commissioning documentation



Appendix WA1: Design

Appendix WA2: Flow measurement and regulation