Factors that lead to cost growth include: inadequate or poorly defined requirements underestimated technical complexity or overestimated technological readiness inadequate project management and acquisition practices a cost estimate of poor quality, whether as a result of inadequate data, methodology or poorly trained cost estimators This guide and the work of the Costing Centre of Expertise aims to address poor quality cost estimates by increasing the capacity to estimate costs in the Government of Canada.
An estimate offers a snapshot-in-time based on available data, such as: how long it will take to build a capital asset whether specialized contractors are available and how much they will cost to hire how many clients will access a service A cost estimate that provides a cost projection far into the future is less certain and at greater risk of being inaccurate compared to one that provides a cost projection for the near future.
The best antidotes for the limitations and vulnerabilities of a cost estimate are: an honest assessment of risk a commitment to refreshing cost estimates as new information becomes available A thorough assessment of risk will help decision-makers allocate an appropriate contingency estimate, and this estimate will increase flexibility when risks are realized. It is important that the departmental culture avoid: being overly optimistic when assessing risks assuming the best possible outcomes will be realized Decision-makers may be misled to believe that sufficient resources have been approved for successful project execution if a cost estimate does not adequately: assess risk due to optimism incorporate appropriate responses.
This section describes five techniques that can be used to estimate costs. For example, regression analysis can be used to identify the relationship between the historical cost of an initiative and one of the key characteristics cost drivers of the initiative, such as: the number of full-time equivalents FTEs the computer processing power required In the case of FTEs, the analysis would determine how the estimated cost would change with each additional FTE.
When planning each step in the cost-estimate production process, these two factors should be considered: The level of effort to develop a cost estimate should be proportionate to factors such as: the importance of the initiative the materiality of the initiative the perceived risk of the initiative relative to the tolerance for risk the level of experience with similar initiatives especially when new technologies are involved The complexity of the planned initiative because the level of complexity will help determine what resources are needed to produce the cost estimate, such as the required knowledge, expertise and analytical tools Step 1: identify stakeholders, the purpose and the boundaries Identify stakeholders and determine their responsibilities.
Stakeholders may include: the manager who is responsible for the new program managers of other programs that might be impacted by the new program representatives from internal service groups The CFO should always be identified as a key stakeholder when a cost estimate is being prepared for a Memorandum to Cabinet or a Treasury Board Submission.
Agree on the purpose of the cost estimate for example, a cost estimate to support a request for project approval. Define the scope of what activities will be included in the estimate, for example: the full life-cycle cost for a departmental asset a limited estimate of the ongoing cost to operate and maintain the asset A common method for documenting and communicating the scope is a cost breakdown structure CBS , which breaks down a project into lower levels of detail.
Define the time frame that the cost estimate will cover for example, the time required to implement a new program, ramp it up and have it reach a steady state. Step 2: collect and normalize data and establish ground rules and assumptions Collect data that is needed to produce the cost estimate for example, historical expenditure data from a comparable program or a similar IT system.
The CBS, described in Step 1, helps to inform the data-gathering process. Normalize the data for consistency and comparability. Data are gathered from a variety of sources and often come in many different forms.
Therefore, they should be adjusted before they can be used for comparative analysis or to project future costs. For example, if a comparable program exists in another country, normalizing would mean converting the historical expenditure data into current Canadian dollars. Establish ground rules. Ground rules for estimating the cost of an initiative are constraints that have been identified by a decision-maker.
Potential constraints can be identified by any stakeholder but, in order to be a ground rule, they should be documented and approved by the responsible program or project manager.
An example of a ground rule is the statement of requirements for a project for example, compatibility with an existing IT or infrastructure platform. Assumptions are used to fill gaps between the ground rules and the available data. For example, the length of time the asset is expected to be in service, and the level of use while the asset is in service.
Typically, assumptions are used at the beginning of the cost-estimating process when there is less data and less certainty. As the estimate matures, assumptions are generally replaced by ground rules and data. Assumptions will often be based on opinions from subject matter experts. However, it is important that these opinions be: reasonable consistent with one another supported by data whenever possible Step 3: create and adjust the point estimate Create a point estimate: by using the purpose, scope and time frame that were defined and agreed to by all key stakeholders in Step 1 that is based on: the data that was collected and normalized the ground rules and assumptions that were documented and approved in Step 2 For multi-year investments, adjust the point estimate for inflation.
Identify risks that should be assessed, mitigated and monitored. Every investment is exposed to schedule risk. Other risks to be considered include: changes in price changes in currency exchange rates the availability of specialized skill sets Provide contextual information to decision-makers about the risks and the potential variation in cost. Explain which inputs generate which costs for example, adding an FTE generates salary and employee benefit costs.
Provide an understanding of how sensitive individual inputs are to change for example, if you add an additional item to a bulk purchase, how does that change the unit cost? Provide an understanding of the uncertainty associated with the estimate and the range of possible outcomes. Uncertainty analysis is focused on the variability of cost inputs and assumptions, which make the future cost of the investment unpredictable. As a result, the final cost will likely not match the cost estimate but will instead fall within a range of potential outcomes.
Determine the appropriate dollar amount to set aside as a contingency in order to account for risk and input variability. The objective of the contingency is to increase the probability that the initiative will be successful within its approved budget. Document the cost estimate.
The level of documentation needed and the level of detail that the documentation should contain should be proportionate to the level of effort invested in developing the cost estimate. Participative : In order for a cost estimate to be credible a wide range of stakeholders and subject matter experts for example, from the responsible manager to representatives of internal services, such as information technology services should participate in its creation.
This broad participation is essential to ensure that: requirements are well defined indirect impacts have been identified suitable sources of data are selected there is agreement on the ground rules and assumptions risk and uncertainty are assessed Comprehensive : A credible cost estimate should clearly define boundaries in terms of time and scope. Time boundary For a new program, estimates would typically include costs to: design and implement the new program ramp up the new program achieve the program's first full year in a steady state For capital assets, life-cycle costs: start to accumulate at conception continue through acquisition and the useful life of the asset include the cost of disposal When there are procurement options, it is important to consider all the life-cycle costs of each option.
For example, the cost to operate and maintain an asset can often be several times higher than the cost to acquire the asset, so these costs are material to the procurement decision. For example, the scope could range from the cost to procure the asset to the total cost of procuring, operating, maintaining and disposing the asset.
Defining the scope determines which costs are relevant. For example, indirect costs, such as internal services, may be excluded from the scope of a project if it is determined that there is no incremental impact on internal services. Data driven: A credible cost estimate is based on good quality data and not opinion.
It is important to be aware that collecting and normalizing data may require a significant investment of time and effort. Data should be the best available and come from an objective, primary source such as the department's financial system If the data is taken from a secondary source, any changes that were made after the data was extracted from its primary source should be documented Data should be up to date for example, if using financial data, it should be from the most recent fiscal period Data should be normalized for example, if the data is in a foreign currency, it should be converted to Canadian dollars Risk-assessed : A credible cost estimate is a prediction of a future outcome that includes a risk assessment.
In order to understand the risk associated with an initiative and the recommended response, a risk assessment should be sufficiently detailed so that the assessment's basis, process, level of subjectivity and findings can be understood. A rigorous risk assessment would: be data driven and quantitative use statistical analysis A less rigorous risk assessment could be based on intuition and qualitative analysis.
For example, a less rigorous risk assessment: might only focus on determining the schedule risk could assume that the probability of a risk occurring and its potential impact are not material Qualitative and quantitative risk analyses are often used together.
For both qualitative and quantitative analyses, it is important to document: how the analysis was done the results of the analysis how the results were taken into consideration Accurate : In order to produce a credible cost estimate: the appropriate cost-estimating techniques should be used the estimates of requirements for future years should be adjusted for inflation the cost estimate should be validated The choice of cost-estimating technique is influenced by a number of factors, such as the maturity of the initiative and the availability of suitable data refer to section 4 of this guide.
Doing so is particularly important: for long-term initiatives during periods of high inflation Not adjusting the estimate for inflation would mean that the initiative will be under funded in future years. Documented : A credible cost estimate should be documented in a cost-estimate report to ensure informed decision-making.
The documentation should: provide a thorough understanding of how the estimate was produced allow readers to assess the credibility and maturity of the estimate be able to withstand scrutiny and an audit allow a third party to reproduce the results. Appendix A: glossary The glossary defines the terms that are commonly used when producing or using cost information in the Government of Canada.
New tasks and technologies are often more complex than expected or forecast. This amount is influenced by risk, uncertainty and sensitivity. The contingency reserve does not provide certainty that the budget will be sufficient. Instead, the objective of the contingency reserve is to provide a reasonable chance of success based on the risk assessment and the risk tolerance of decision-makers, which can vary by initiative.
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This methodology is crystallized through the formulation of an optimization model LCCA-SSL which integrates both LCC and LCA methods to help construction stakeholders in the decision making for the most sustainable lighting systems and lighting sources. This implementation can be part of an overall value engineering scheme. In an attempt to face the global problem of energy consumption, a case study has been selected to compare between two lighting systems; Conventional System and Photovoltaic Solar System, and their corresponding lighting sources; namely, light emitting diodes LED , high pressure sodium HPS , and metal halide MH within a 10 years period of analysis.
A sensitivity analysis was conducted in order to measure the impact of changing certain variables such as the interest rate, the inflation rate and the period of analysis, where there is uncertainty in their assumption, on the LCC of each of the alternatives.
The model proposed in this study is user friendly and can be used by different construction stakeholders to optimize the use of systems and sources of lighting under environmental and long-term constraints. I Abstract II List of Figures VII List of Tables IX Chapter 1: Introduction……………………………………………………………………………1 1. One of the areas which constitute the main bulk of economic and environmental impacts was chosen to be the focus of the study.
This area is the electricity utilization in lighting Khasreen et al. Sustainability is a concept widely used nowadays after the huge on-going development in the world which has a major negative impact on the environment.
Despite of its importance, sustainability is studied only in the developed countries, while developing countries do not pay much attention to its significance. Consequently, developing countries are suffering from natural resources depleation and lack of affordable alternatives. Accordingly, this leads to the importance of educating people about sustainability in schools, universities as well as awareness campaigns and training courses about sustainability application and its benefits to environment and individuals.
The concept of sustainability was originated in forest giving the meaning of preserving natural resources for the future or never harvest more than what the forest yields in the new growth Kuhlman et al. Afterwards, in the concept was presented in the report of the Club of Rome and gave a very pessimistic view about many natural resources crucial to the human survival, that they shall be exhausted within the next one or two generations Kuhlman et al.
Therefore, the UN Commission made a report on environment and development to find a way for solving this problem, namely the Brundtland Report named after the UN Commission chairperson Kuhlman et al.
The Brundtland Report was in ; it adopted the sustainability concept and made it well-known Kuhlman et al. This report raised the very important question of how to proceed with development with sustainability and accordingly it came up with the term sustainable development giving it the definition stated above Kuhlman et al. Etkins states that weak sustainability intends that human welfare is not dependant on a specific form of capital and that man-made capital can substitute natural capital but with limitations Etkins, However, strong sustainability means that man-made capital and natural capital cannot substitute each other Etkins, However Kuhlman et al.
First, the economic aspect is concerned only with money and this is a very limited view of economics. Second, the gross domestic product GDP is intended to measure the welfare of people from only a materialistic view; however it needs to be complemented by other indices such as the human development index.
Accordingly it tackles the economic pillar of sustainable development. Hence, LCA tackles the second pillar of sustainable development which is the environment.
The energy products and consumption problems are affecting the whole world nowadays. Accordingly, there are different approaches aiming at finding energy saving solutions. However, these studies are not widely spread and their applications in the developing countries in general and in Egypt in specific are almost nonexistent.
One of the most important components to be studied because of its large amount of energy consumption which affects its life cycle cost and environmental impact is lighting systems and sources. On the other hand the residential and industrial sectors consume the main bulk of electricity utilization in Egypt with a Figure 1.
Ibrahim Yassin Consequently the development of a new model which integrates life cycle costing and life cycle assessment methods and techniques for the optimization of the use of the most feasible and environmental friendly lighting systems and sources shall enhance the construction industry competitiveness in Egypt.
A software optimization model shall be developed based on the proposed approach to facilitate the calculation process. The main objectives of the developed model could be summarized as follows: 1. Determination of the most economic lighting system and source which can be used in different sectors such as residential, commercial, streets, and office buildings in Egypt. Determination of the most environmental friendly lighting system and source which has the least environmental impacts in terms of energy consumption and CO2 emissions during its usage phase.
Comparison between the conventional lighting system and source and the energy- saving lighting system and source in terms of their life cycle costs, energy consumption and CO2 emissions. This model shall be finally validated through a case study in Egypt. A brief synopsis of these chapters is described below: Chapter 2: Literature Review: Presents a literature review on the topics of LCC and LCA; their history, definitions, and methodologies.
Chapter 3: Lighting Systems and Sources: Discusses the current lighting systems and sources; their types, specifications, and applications. Chapter 4: Methodology and Analysis: Presents the methodology of this research which consists of the questionnaire data collection and analysis and the LCA and LCC methodologies adopted in this research.
Chapter 6: Conclusion: Concludes the research and summarizes the final results of the case study, as well as giving further recommendations for future research. It is used, mainly, for the comparison between the life cycle costs of two or more alternatives.
In general, stakeholders decide on the more economic investment by comparing only between their initial capital investment costs. In particular it is an economic assessment considering all the projected relevant cost flows over a period of analysis expressed in monetary value. It may only be beneficial if we are calculating the payback of an asset. In order to apply LCC there has to be a known rigid methodology, cost breakdown structure, and an accurate source for the data collection and this is what the next paragraphs will enlighten.
However, the costs to be included in the Life Cycle Costing study differ from one standard to another as they differ among countries and projects. Also, the costs included differ according to the nature of the study. Either it is studying the life cycle cost of a product or an asset by its own, for example, to study its payback period or it is comparing the life cycle cost among two alternative products or assets to decide to invest in which of them.
It is obvious from literature that there is confusion between the meaning of the whole life cost and the life cycle cost, as in various papers they are considered as one. However, as shown in figure 2. Figure 2. The breakdown of LCC costs including the occupancy costs is shown in Appendix A; this breakdown can be tailored as well according to the country and the type of project. Construction costs differ according to the type of project.
For example, the construction costs of a hospital may include several items which are not to be used in the execution of a residential building and vice versa; this in addition to the method of construction.
Operation costs are periodic costs which include internal and external cleaning, utilities such as electricity, gas, water and drainage … etc, administrative costs such as property management, waste management and disposal, and staff engaged in servicing the building, overhead costs such as insurance, lease, and finally taxes, rates and other local charges payable with owning the building.
It is also referred to as the residual value. Costs which include those of inspections carried out before demolition, costs of demolition, costs of repair done at the end of the period because of a contractual obligation to return the building on an agreed condition. Discount rate does not reflect the decrease in the value of the asset due to price movements resulting from its degradation by time.
However, it reflects the changes of the asset due to the interest rate earned on the money of the asset combined with its value decrease due to inflation. Discount rate is divided into two types: real discount rate and nominal discount rate. According to the life cycle costing handbook, both real and nominal discount rates give the same result as long as each is included in its corresponding present value calculation.
Consequently, the exclusion of the real discount rate to the inflation rate does not mean it is ignoring it. The decision of using real or nominal discount rate is dependent on the decision of usage of constant dollars or current dollars. Real discount rate is used in calculation when constant dollars are used; on the other hand, nominal discount rate is used in calculation when current dollars are used Fuller et al.
In this research the nominal discount rate shall be used because of the instability of the Egyptian industry nowadays which leads to the huge increase in the Egyptian Pound inflation rate. The findings of this project provide a general framework for the application of LCC across EU without replacing country-specific decision models and approaches. It is divided into 15 generic steps refer to Table 2.
This framework is based on the core process of LCC refer to figure 2. There are different methodologies for the calculation of the life cycle cost of an asset such as present value which is the most widely used, simple payback, discount payback, equivalent annual cost, internal rate of return, and net saving refer to table 2.
It depends on converting all the future and annual cost into present value and this of course requires the involvement of inflation and interest rates. It compares the alternative assets in terms of payback periods and the one with the shortest payback period is the one to be chosen.
The simple payback method ignores the inflation and interest rates of money. The alternative with the highest rate of return is the most profitable Schade, n. The alternative which has higher net saving is the most profitable Schade, n. Table 2. The results of the LCC shall be based on two calculation methods which are the equivalent annual value and the net present value. Since the LCC study is built on estimation of future data so there has to be a reliable method for data collection for the reduction of uncertainties.
The analogous cost method is based on historical data from similar built projects with similar components and products. Therefore, in order for the LCC study to have sense and to be beneficial the final result has to be indicative Tupamaki, Construction projects life span ranges from 20 to 50 years, as a result, many changes will probably happen such as fuel prices, building products prices and service lives … etc.
Fawcett et al. This means that the estimation of a detailed and accurate future costs is impossible Fawcett et al. Deterministic Results Since the s and till recent years the LCC study used to use the deterministic approach refer to figure 2.
Afterwards, the probabilistic approach has taken its way into emergence and since then it is under research. The probabilistic approach encompasses a range of values for life cycle cost. The range of results are calculated using the 3-point estimate method lowest conceivable value, most likely value and highest conceivable value in order for the results to be more realistic Fawcett et al, n.
Nevertheless, one of the difficulties faced in adopting the LCC technique in Egypt is the non-existence of a software model which facilitates the calculation of the LCC. However each has different calculation technique and requires different inputs.
Edvardsen, n. User-friendly; facilitates the estimation of the LCC in terms of not requiring too many and complex input data by the user; 2. Flexible; has an easy access to its database to change the costs and rates which will change with time.
Available in the Egyptian Market with its manual and affordable training courses in the large Egyptian construction companies in order to encourage the construction companies to use it. Construction materials and products such as different types of bricks, wood … etc. Electrical systems such as lighting systems; 3. Mechanical systems such as HVAC and heating systems.
On the other hand, during the operation phase, the environmental impact of the building sector does not come to an end. However, it is still causing environmental impact through heating, ventilation, maintenance, and alteration Sterner, The reduction of these environmental impacts has become highly needed. There are other techniques used for environmental impact assessment; however LCA is the most important because it evaluates the life cycle of the asset from the acquisition to disposal.
LCA can be used as a tool for decision-making for purchasing products or implementing designs taking into consideration their environmental impacts.
The assessment includes the entire life cycle of the product, process or activity, encompassing extracting and processing materials; manufacturing, transportation and distribution; use, reuse, maintenance; recycling and final disposal. The next paragraphs will explain the framework of LCA, its methodology, and modeling.
This definition stage should be as much detailed as possible covering the function of the building, its geographical location, the system boundaries meaning a component of the building, a phase in the building life cycle or the whole building life cycle will be studied Khasreen et al.
It should, also, include the functional units which could be m2, m3, number of occupants …etc. Because this stage is mainly reliant on assumptions and because the buildings have long life span, the goal and scope definition phase has to be reviewed and modified after each phase Khasreen et al.
It is the most complex and difficult stage since it involves the collection of all relevant inputs and outputs of energy, mass flow, and emissions to air, water and land Khasreen et al. The construction phase, construction wastes and the transportation of equipment to site are not to be included in the LCA study Khasreen et al. According to ISO , the inventory analysis procedure involves the data collection, data calculation, data validation, relating data to unit processes and functional unit, and data allocation when the study is involving recycling Langdon, The need for allocation changes according to the size of the system boundary; as the system boundary increases, the need for allocation decreases Khasreen et al.
Foreground data: very specified data about the product or the system 2. Background data: generic data accompanied with the process such as transportation, energy, materials … etc. For example, the foreground data may be collected through questionnaires to suppliers, consultants, or people related to LCA studies and research.
The nationality of data is a very important concern as methods of construction, production of materials, resources used … etc. Data quality, accuracy and completeness are very important since the life cycle inventory data drives the study of the LCA and determines its success or failure. Any changes or inaccurate data may lead to wrong results; in addition to that the incompleteness of the data may lead to the change of the goal and scope definition as well as the system boundaries Khasreen et al.
Thus the choice of a reliable source of data is a must. Before starting the main steps of LCIA, it is important to first select and define the impact categories related to buildings which some of them are shown in table 2. These impact categories differ from a study of a building to another building according to the goal of the study, the data availability, the significance of the impacts Khasreen et al.
Ammonia NH4 Air pollutants, waste water and Phosphate PO4 fertilization in agriculture Nitrogen Oxide NO enriches nutrients in water and Nitrogen Dioxide NO2 land, resulting in algae growth in Nitrates, and Ammonia Eutrophication E waters, thus fish dying due to NH4 lowered oxygen concentration, and plants prone to diseases and pests, and other problems.
This process is called Characterization. It is done only for better comprehension of the LCIA results which were calculated in the Characterization step. The total result of each impact category is called impact indicator. For example the impact indicator of global warming of an LCA study of a building is a certain amount of CO2 emission.
For instance, the CO2 emission in year is used as a reference case to assess the CO2 emission in the future.
The existing value can be divided by the reference value for obtaining an index value Langdon, As the impact indicators total results calculated from the normalization step have different effect on the environment, they have to be assigned to weights to indicate the severity of each. However, the process of weight assigning is subjective and may lead to controversy.
Impact categories can be grouped according to their global significance, local significance, geographical relevance, or company priorities … etc. Langdon, It is considered the presentation of all the previous phases in an analytical way. In this phase all the results are analyzed in a way showing which the prevalent impact category was, the one having the highest environmental impact so that it can be underlined as the most problematic that needs a mitigation solution, the limitations of the study and the recommendation for the future LCA or LCI studies … etc.
Khasreen et al. Uncertainty may result from the estimation of future environmental impacts or data collected via questionnaires or data incompleteness. Accordingly, it is important to apply a method to deal with this uncertainty problem. The sensitivity analysis is done in order to evaluate the magnitude of the assumptions done. So assumptions are evaluated through changing them and recalculate the LCA again.
Some are done for building products while others are done for materials and others for designs comparisons etc. To facilitate the use of LCA in Egypt as well as in any other country, there has to be a model which can be easily accessed with its database which can be modified according to the type of asset studied whether it is a whole building, a product, a material … etc.
This model has to calculate the LCA result taking into consideration sensitivity analysis done in order to consider results uncertainty. Eventually, it has to have a cost output to be tangible and more catching to the user. The LCA model can be used in Egypt for studying the environmental impacts from cradle to grave of the following in order to enhance the sustainability of the Egyptian construction industry: 1.
Construction materials and products in different sectors residential, commercial, industrial …etc. Electrical systems in different sectors 3. So they both can be integrated in several ways. But here comes the question of how to integrate LCA results, which are environmental indicators, and LCC results which are costs. How to integrate two results of different nature together?
Accordingly, one has to take the quantity and quality of lighting into consideration while searching for other alternatives better than conventional lighting in terms of energy consumption and environmental impacts.
Lately, many researchers are directed towards finding methods for saving energy. Energy consumption is mainly distributed among four sectors commercial, residential, industrial and transportation. Electricity has a great impact on energy consumption. Figure 3. However, according to Dr. Ibrahim Yassin.
There are several measurements for light intensity such as Lux and Lumen. Lux is the amount of light reaching a subject. One lux is equal to ten foot-candles Helal, Outdoor average sunlight ranges from 32, to , lux 2. Moonlight is about 1 lux 3.
Warehouse aisles are lit to approximately to lux 4. An office requires about lux 5. At sunset and sunrise with a clear sky , ambient outdoor light is about lux 6. Building corridors can be lit by about lux Lumen is another measurement of lighting. It is the amount of light that a bulb produces. The lighting intensity of all lamps is measured in lumens Helal, A W Metal Halide lamp — for high bay warehouse lighting: 38, Lumens 2.
Photopic Lumen is the one measuring the intensity of the outdoor lighting Helal, n. Standard lumen and foot-candle meter is the measurement of photopic lumen Helal, n.
Scotopic lumen is the other type of lumen measuring the indoor lighting intensity Helal, n. Scotopic lumen cannot be measured directly with a standard light meter Helal, n. The amount of lux light intensity needed to light up an area of a square meter is equal to the amount of lumen produced by a bulb concentrated on that area. This means that lumens which are concentrated on an area of one square meter are resulting in lux of light intensity.
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