No abstract

No abstract

Standard-Nutzungsbedingungen:Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden.Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen.Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. The views expressed in this paper are those of the author and do not necessarily reflect the views and policies of the Asian Development Bank (ADB) or its Board of Governors or the governments they represent. Terms of use: Documents inADB does not guarantee the accuracy of the data included in this publication and accepts no responsibility for any consequence of their use.By making any designation of or reference to a particular territory or geographic area, or by using the term "country" in this document, ADB does not intend to make any judgments as to the legal or other status of any territory or area. Note: In this publication, "$" refers to US dollars.The ADB Economics Working Paper Series is a forum for stimulating discussion and eliciting feedback on ongoing and recently completed research and policy studies undertaken by the Asian Development Bank (ADB) staff, consultants, or resource persons. The series deals with key economic and development problems, particularly those facing the Asia and Pacific region; as well as conceptual, analytical, or methodological issues relating to project/program economic analysis, and statistical data and measurement. The series aims to enhance the knowledge on Asia's development and policy challenges; strengthen analytical rigor and quality of ADB's country partnership strategies, and its subregional and country operations; and improve the quality and availability of statistical data and development indicators for monitoring development effectiveness.

No abstract

Change orders impact many areas of a construction project. However, the impacts that change orders have on labour efficiency are much harder to quantify than other impacts and therefore are a significant risk to contractors. Little research has been completed in the past quantifying these impacts, so disputes are common between owners and contractors regarding the actual cost of change. This study used data from 43 projects to develop a linear regression model that predicts the impact of change orders on labour efficiency. The input factors needed for the model are (1) total actual project hours, (2) total estimated change hours, (3) impact classification, and (4) timing of change. The model calculates the labour loss in efficiency for a particular project so that owners and contractors will better understand the true impact of change on labour efficiency. The research is limited to the mechanical trade, but does include specific work in plumbing, HVAC, process piping, and fire protection.Labour Efficiency, Productivity, Impacts, Change Orders, Mechanical Contractors,