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An analytical approach for explaining the variability in labour intensive construction operations has been developed. A consistent method of collecting productivity developed jointly at the Pennsylvania State University and the University of Dundee has been refined and tested. Data has been collected daily from seven Scottish sites for continuous periods of up to 3 months. Not only productivity but many of the factors affecting it have been measured. A comprehensive, computerised database has been designed to facilitate data storage and manipulation. The quantification of the impact of each individual factor is based on the assumption that deviations from an operative?s normal output arise because of disturbances imposed by a multiplicity of site factors. The impact of each individual factor causes the average daily productivity to change.

Riyadh city suffers from high housing and construction costs, which have increased by more than 200% over the last 7 years. This problem led to a significant interest from the government and the citizens of the city in understanding the causes of housing and construction cost escalation and the best strategies to address this problem in the short and long-terms, in order to find solutions for affordable housing. In response to the absence of research regarding this problem, the researcher has decided to conduct a scientific survey about the factors that might have led to this problem in Riyadh. While conducting the literature review, the researcher identified 16 possible factors that were mentioned as possible causes for this problem. Thus, the main objective of this study is to identify the main factors that affect housing cost escalation. All of the survey samples were collected from construction industry professionals and experts working in Riyadh. The sample size required was calculated using the statistical equation mentioned in Chapter 4, and based on an estimated level of confidence of 90%, standard error of 10%, and a standard deviation calculated from 30 random samples collected initially. The required sample size was estimated to be at least 215 surveys, and the researcher was able to collect a total of 237 surveys. After collecting the data, the researcher analyzed the data through Microsoft Excel software by applying descriptive statistics, means, modes, and standard deviations. Tables and figures have been used to show the results of the survey. After analyzing the data, the researcher identified the main factors based on the mode and mean averages. The researcher has identified four major impacting factors that affected housing and construction costs. The most impacting factors on housing and construction cost are the corruption in selling land, speculative purchases of land, high demand for housing, and the high population growth rate in Riyadh. The main recommendations that should help the government to solve this problem are: to apply an annual tax on large plots, prevent speculative purchases in housing areas, monitor the prices of consruction materials, and revive small cities around Riyadh to reduce congestion and crowding.

Breaking Through the First Cost Barriers of Sustainable Planning, Design, and Construction John W. Mogge Jr. 377 Pages Directed by Dr. Rita Oberle The research integrates elements of the bodies of knowledge for sustainability, planning, design, and construction to create an understanding of green project first cost drivers. It extends conceptual models for sustainable infrastructure and the built environment process by creating a framework based linkage to analyze first cost impacts of sustainable project planning, design, and construction decisions. The framework functions as an analytical bridge between the built environment process and sustainability and is the principal contribution of this research. Through a preliminary analysis of fourteen projects, the work draws out relevant planning, materials and methods, and estimating and scheduling best practices and guiding principles. The work then proposes a first cost impact framework derived from the preliminary analysis as a decision support tool and tests the framework using an expert system derived linguistic database. The test results support the functionality of the framework. The test linguistic database was developed through an interdisciplinary professional expert practitioner interview process using common green project planning, design and construction strategies. The qualitative, interpretative, multi-criteria analysis of the data used fuzzy set theory and presents findings helpful in understanding green project first cost drivers. The work concludes with an assessment and a discussion of parallel research, and ten recommended areas for further research.

Best value is becoming one of the most commonly used procurement methods in the facility construction industry. The Federal Government and the Air Force Reserve predominant project delivery approach has been via the low-bid award. This process has not been successful, documented by large numbers of construction modifications, as well as project cost and schedule growth over the past sixteen years. Recently, federal procurement agencies have attempted to move toward construction awards based upon best value principles relative to performance and price. The United States Army Corps of Engineers best value procurement vehicle known as Military Transformation fails to deliver true best value. This pseudo best value delivery process: (1) fails to objectively rate and apply contractor past performance; (2) lacks the means to monetarily quantify contractor proposal risks; and (3) provides no means of transferring control and responsibility for risks and risk minimization to the contractor. Only a true best value project delivery system can provide the urgently required increased efficiency necessary for Air Force Reserve Command to remain a dependable military institution capable of erecting facilities contributory to our nation's defense by perpetually adding value to the project delivery process.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The construction industry is a competitive market and contractors need to keep up-to-date with new construction methods and technologies. Project teams in South Africa are required to make decisions during the early stages of construction projects. These decisions often need to be made in a short time period, and include the decision between various construction methods, such as the decision between in-situ concrete construction and hybrid concrete construction. Hybrid concrete construction is a combination of pre-fabricated concrete and cast in-situ concrete to obtain the supreme benefits of their different construction qualities. This method of construction is ultimately used to achieve faster, and occasionally, more cost effective construction. Hybrid concrete construction, today, is a well-known term in the construction industry and is widely used in the UK and other developed countries. However, the use thereof is limited in South Africa, and in-situ concrete construction remains the conventional method of construction. Possible reasons for the limited use of hybrid concrete construction are investigated in this study. With the intent of improving the construction industry of South Africa, guidelines are provided to assist project teams in a decision between in-situ concrete construction and hybrid concrete construction. The decision between construction methods is based on many factors, such as project time, cost, quality, safety, environmental performance, socio-economic aspects (labour) and client satisfaction. Project time and cost are, however, the most important of these factors. It is stated that the structure of a building represents typically only 10 % of the construction cost, however, the choice of construction method and material can have significant effects on the cost of other elements throughout the life cycle of construction projects. It is therefore important to measure the whole life cycle cost when deciding between construction methods, such as in-situ concrete construction and hybrid concrete construction. The aim of this study is to identify and investigate the factors that influence project time and cost, throughout the life cycle of construction projects, and to provide a framework that can assist project teams in their decision between in-situ concrete construction and hybrid concrete construction in South Africa. The decision between these two construction methods is influenced by a vast number of variables that may be difficult to quantify. The framework therefore consists of qualitative information that can assist project teams in their decision. The framework provided in this study includes the factors that have an influence on the time and cost for a decision between in-situ concrete construction and hybrid concrete construction. These factors are identified for the three primary phases in the life cycle of construction projects. These phases are the design phase, the construction phase and the maintenance phase. / AFRIKAANSE OPSOMMING: Die konstruksiebedryf is 'n kompiterende mark en kontrakteurs moet op datum bly met nuwe konstruksie metodes en tegnologieë. In Suid-Afrika word daar van projek spanne vereis om vinnige besluite gedurende vroeë stadiums van 'n projek te neem. Hierdie besluite moet dikwels in 'n kort tydperk geneem word, en sluit die besluit tussen verskillende konstruksie metodes in, byvoorbeeld die besluit tussen in-situ en hibriede beton konstruksie. Hibriede beton konstruksie (HBK) is 'n kombinasie van in-situ en voorafvervaardigde beton elemente. HBK word in die algemeen gebruik om te baat uit 'n vinniger konstruksie tydperk, en kan soms ook ‘n meer koste-effektiewe metode van konstruksie wees. HBK word gesien as 'n bekende term in die konstruksiebedryf en word veral toegepas in ontwikkelde lande soos die VSA, Japan en Engeland. Die toepassing daarvan in Suid-Afrika is egter beperk. In Suid-Afrika word in-situ beton konstruksie nog steeds die meeste gebruik en staan dus bekend as die mees algemene metode van konstruksie. Hierdie studie ondersoek moontlike redes vir die beperkte gebruik van HBK in Suid-Afrika. Met die oog op 'n verbeterde konstruksiebedryf in Suid-Afrika, word rigylyne voorsien, wat projek spanne kan gebruik vir 'n besluit tussen in-situ en hibriede beton konstruksie. Daar is verskeie faktore wat 'n rol speel in die besluit tussen twee konstruksie metodes. Hierdie faktore sluit in, die tyd, koste, kwaliteit, veilighed, omgewings impak, sosio-ekonomiese aspekte (soos arbeid) en kliënt tevredenheid, van 'n projek. Tyd en koste is egter die belangrikste van hierdie faktore. Die metode waarvolgens 'n struktuur gebou word kan 'n beduidende uitwerking op die koste van ander elemente in die lewensiklus van 'n konstruksie projek hê. Dit is gevolglik belangrik om die hele lewensiklus koste in ag te neem wanneer daar besluit moet word tussen verskeie konstruksie metodes, soos in-situ en hibriede beton konstruksie. Die doel van hierdie studie is gevolglik om die faktore wat 'n invloed het op die tyd en lewensiklus koste van konstruksie projekte te identifiesieer. Hierdie faktore word dan gebruik om 'n raamwerk voor te stel. Projek spanne kan hierdie raamwerk gebruik as 'n riglyn om te besluit tussen in-situ en hibriede beton konstruksie. Die besluit tussen hierdie twee konstruksie metodes is afhanklik van 'n groot aantal veranderlikes, wat moeilik is om te kwantifiseer. Die raamwerk bestaan dus uit kwalitatiewe inligting wat projek spanne kan gebruik om 'n ingeligte besluit te neem oor in-situ en hibriede beton konstruksie. Die raamwerk wat in hierdie studie voorgestel word sluit dus die faktore in wat 'n invloed het op die tyd en koste vir 'n besluit tussen in-situ en hibriede beton konstruksie. Hierdie faktore is geïdentifiseer vir die drie primêre fases in die lewensiklus van 'n konstruksie projek. Hierdie fases is die ontwerp fase, die konstruksie fase en die onderhoud fase.