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  • PublisherCIBSE, CIPHE & Heriot Watt
  • Product CodeSTB1601
  • Number of pages10
  • Publication DateDec 2016
  • ISBN

TB16 01 Domestic Water Demand Assessment for Pipe Sizing

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TB16 01 Domestic Water Demand Assessment for Pipe Sizing

SoPHE Technical Bulletin TB 16-01

In terms of domestic water pipe sizing, the industry is in a period of transition. Reliability questions are being raised about the traditional demand assessment system based on the LU (loading unit) method that was introduced to the UK in 1965. This was prior to the advent of water efficiency considerations, when washing habits were very different, and when mixer taps and automatic white goods where uncommon in dwellings.

Based on empirical data from live buildings, and also considering alternative design methods used in similar European countries, the growing consensus is that the UK LU system will significantly over–estimate the peak simultaneous design flow in multi-residential buildings. This TB provides interim best practice guidance for assessing domestic water demand for pipe sizing in various applications, that can be used until such time as further research is completed (e.g. LUNA1) and/or new design standards have been published.

This technical bulletin has been written by Brian Whorlow BA (Hons) IEng FCIPHE, who is honorary Chair of the LUNA group.

Contents:

About the author
Summary of key items for consideration
Background
What is the origin of UK loading units?
Inherent loading unit problems
Over-sizing problems
Design Standards
Design methods for multiple residential buildings
Design methods within single dwellings
Design methods for commercial buildings
Design methods for congested applications
References

See also:
LUNA: An Assessment of Loading Units Method for Sizing Domestic Hot & Cold Water Services - A CIPHE, CIBSE & Heriot Watt Joint Research Report - which is available here