Planning and Scheduling Construction Projects, Part 1: The Planning Process
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The document provides guidance on developing and reviewing baseline construction schedules. It discusses common planning problems, the importance of the planning process before scheduling, and key elements to define the schedule basis including assumptions, exclusions, constraints, and more. It also covers estimating construction durations using productivity rates, developing resource loaded schedules, and factors that can impact the baseline schedule such as location, labor availability, and construction methods.
Planning and Scheduling Construction Projects, Part 1: The Planning Process
- 2. Alberto Sanchez BEng, MsCLog, MIntBus, GradCertEnSt Alberto has over 20 years of experience delivering capital projects with values from $100 million to over $10 billion in Asia‐Pacific, Middle East, Europe and Central Asia and Latin America in the private and public sector. He has worked across different industries including oil and gas, chemicals, utilities and infrastructure throughout all project phases (feasibility studies through to commissioning) as project controls manager, head of project controls, planning manager and head of capital projects for international oil companies, E&C contractors and consulting firms 2 Alberto holds a bachelor degree in civil engineering, master degree in logistics and operations, master degree in business and postgraduate in energy studies from recognised Australian universities. He is often requested as a keynote speaker at major companies and industry conferences worldwide on planning/scheduling, risk management and modular construction. He is always interested in hearing from former colleagues, clients, or just interesting folk, so feel free to contact him
- 3. Contents • Part 1: The Planning Process • Common planning problems • The planning and scheduling process • The schedule basis • Productivity rates and construction durations • Resource loaded schedules and resource leveling • Some factors impacting the baseline schedule • Part 2: Schedule Assurance Review • Schedule quality review • Schedule risk review • Schedule benchmark review • Conclusion 3 Prepared by A. Sanchez
- 4. Common planning problems Pre‐Award Post‐Award Bid / No‐Bid Phase Bid Phase Initiation Phase Execution Phase • Schedule benchmark is not applicable or incorrect (e.g. different country) • Proposal schedule is developed without clear execution strategies • Proposal schedule does not fully reflect the project scope • Failure to develop unbiased proposal schedules (over optimistic schedule) • Proposal schedule is developed by planners/schedulers with limited experience • Durations are estimated without key info such as quantities, local content, construction methods, etc. • Lack of centralised database with productivity rates and project historical data • Poor identification and quantification of schedule risks and opportunities during the proposal schedule development • Baseline schedule does not reflect the final negotiated scope • Poor identification and quantification of schedule risks and opportunities during the baseline schedule development • Baseline schedule is developed by planners/schedulers with limited experience • Difficulties to transfer schedule liabilities to subcontractors and suppliers • Lack of knowledge and/or understanding of contractual obligations • Delay in payment milestones leading to negative project cash flows • Extra costs to avoid schedule penalties (e.g. overtime, additional workforces, extra supervision, etc.) • Difficulties to demonstrate valid extension of time claims to clients • Lack of centralised database with productivity rates and project historical data Prepared by A. Sanchez 4
- 6. Planning vs. Scheduling • Do you know the difference between planning and scheduling? • Many companies think that the two are the same • Planning should always be before scheduling • Before we attempt to develop our proposal or baseline schedule, we must have a clear understanding of the project plan 6 Planning Scheduling Baseline Prepared by A. Sanchez
- 8. The schedule basis (1 of 3) Before developing the proposal or baseline schedule important elements such as assumptions, exclusions, constraints, etc. must be defined and understood. These elements form the schedule basis, such as: • Sectors of construction or industry – e.g. oil & gas production facilities, chemical plant, power plant, highways and roads, etc. • Location of the construction site(s) – e.g. distance to borrow pits and quarry, location of labor accommodation camp, etc. • Local codes, standards and permits • Site access and weather restrictions – e.g. rainy season, cold weather • Temporary construction activities – e.g. temporary access roads, temporary utilities, relocation of existing overhead or underground lines • Construction priorities, logic and sequences • Interfaces with existing facilities in operation – e.g. revamps, shutdowns, modernisation, expansions • Interfaces with other contractors – e.g. site preparation, drilling, utilities Prepared by A. Sanchez 8
- 9. The schedule basis (2 of 3) • Interfaces with local communities and regulatory bodies – e.g. traffic and local roads, noise levels, etc. • Working calendars – e.g. 6‐day calendar, 7‐day calendar, crew calendars, weather calendars, rotation calendars, public holidays • Construction methods and procedures – e.g. modular components, stick‐ built or traditional, prefabricated elements, pre‐cast concrete • Special construction equipment requirements – e.g. heavy‐lift cranes, barges, pipelayer, concrete batch plant, etc. • Expected productivity rates (NORMs) • Labor requirements – e.g. local content laws, labor union requirements • Labor availability and possible overtime, rosters • Construction subcontract arrangements • Establish construction camp, material laydown area and storage facilities • Completion of approved drawings and design documents for construction Prepared by A. Sanchez 9
- 10. The schedule basis (3 of 3) • Material and equipment deliveries • Manufacturer or supplier scope – e.g. on‐site assembly, transportation, preservation and storage, supervision, site testing • Fabrication shop versus field fabrication • Safety requirements – e.g. confined spaces • Protection of completed work(s) • Client requirements – e.g. hold points and key inspection dates • Others Prepared by A. Sanchez 10
- 11. Different construction sectors Productivity rates, design codes, safety and quality requirements, construction techniques, legal aspects, approval processes and other factors can vary dramatically depending on the sector for which the construction is required. Prepared by A. Sanchez 11 Oil & gas production facilities Textile mills Chemical plants Pharmaceutical plants Steel / aluminum mills Power plants Manufacturing facilities Food processing plants Refineries Heavy construction Civil and infrastructure Building and residential Plant upgrade/retrofit
- 12. Construction priorities, logic and sequences Before developing the schedule, other key planning elements must be defined such as: • Priorities or phases – design phase, temporary construction phase, early production phase, pre‐shutdown phase, pre‐ commissioning phase, etc. • Work Breakdown Structures (WBS) – the project schedule must be broken down into its component parts (e.g. process unit, utilities, storage, etc.) and/or work packages (e.g. substructure works, mechanical works, piping works, electrical works, etc.) • Logic and sequences – construction activities must follow a determined logic to deliver the project in the right sequence depending on the proposed construction method(s) Prepared by A. Sanchez 12
- 13. Construction priorities, logic and sequences • Work Breakdown Structures (WBS) Prepared by A. Sanchez 13 Example: WBS or work packages of industrial process plant 1000 Industrial Plant 1000 Utilities 1100 ‐ Potable water 1200 ‐ Waste water 1300 ‐ Electrical 1400 ‐ Plant air 2000 Storage and Handling 2100 ‐ Warehouse 2200 ‐ Handling 2300 ‐ Chemicals 3000 Process 310 ‐ Process train 3200 ‐ Process buildings 3300 ‐ Product storage 4000 Support 4100 ‐ Office and admin buildings 4200 ‐ Roads and carparks 4300 ‐ Landscape
- 15. Labor productivity rates • Labor productivity rate is the number of labor hours (work effort) required to complete a defined construction activity (NORM or benchmark) • Each productivity rate is a typical or average number of labor hours required by the group of all individuals (i.e. crew) associated with the construction activity • Base productivity rate is adjusted by factors such as: labor density, facility complexity, overtime, weather, shifts, labor quality, labor availability, greenfield vs. brownfield, elevated work, geographic location, security, etc. • A table should be provided in the schedule basis showing the productivity rate applied for each type of work (e.g. piping works, concrete works, steel works, etc.) Prepared by A. Sanchez 15
- 16. Labor productivity rates • Comparison of labor productivity in different countries Prepared by A. Sanchez 16 COUNTRY LABOR PRODUCTIVITY RANGE (*) GOOD AVERAGE POOR Australia 1.05 1.20 1.50 Brazil 1.30 2.25 2.85 India 1.75 2.30 2.80 Indonesia 2.50 2.80 3.20 Iraq 2.00 ‐ 3.50 Nigeria 1.75 2.25 3.35 Russia 1.25 1.75 2.25 South Africa 1.20 1.40 1.95 South Korea 0.95 1.20 1.65 Azerbaijan 1.50 ‐ 1.85 Kazakhstan 2.00 ‐ 3.00 * Source: Global Construction Cost and Reference Yearbook. 2015 Annual Edition
- 18. Construction durations Estimating construction activity durations (key terms) • Effort‐driven duration – estimate based on the work volume or bill of quantities (BOQ) and expected productivity rate (duration = work quantity / productivity rate) • Fixed‐duration – estimate based on amount of calendar time available for the activity completion (e.g. shutdown window, track possession, weather window) • Forward schedule – from project start to finish, calculate the earliest each activity can start and finish according to the sequence of work and the duration of the predecessor activity • Back‐end driven schedule – working backward from project finish to start, calculate the latest each activity must start and finish to meet the project end date Prepared by A. Sanchez 18
- 20. Construction durations • Example: estimated duration of piping work for a new industrial plant in Uzbekistan Prepared by A. Sanchez WBS Plant Area Quantity (diameter‐ inches) Quantity (Work Split) Total Crews Productivity Rates per Crew (diameter‐inches per day) Duration (in days) Shop Site Shop Site Shop Site Shop Site Utilities 54,720 DI 33,304 DI 16,416 DI 12 14 16 6 173 195 Storage 39,520 DI 27,664 DI 11,856 DI 12 12 14 4 165 247 Process 54,720 DI 38,304 DI 14,416 DI 12 12 14 4 228 300 Piping Crew 1 Welder 2 Fitter(s) 1 Helper Estimated number of crews or workers (based on labor density values, labor resources requirements, labor availability, etc.) Productivity rate Estimated duration Estimated quantity (BOQ) Location of construction site Quantity (BOQ) number of crews x productivity rate per crew
- 21. Resource loaded schedules • Resource loaded schedule – consists of a timeline with details on assigned resources (labor, construction equipment, tools and key quantities) • Manpower plan – this plan focuses on estimating the size of workforce, division in disciplines and scheduling the deployment of required manpower • Resource leveling – as defined by PMBOK “is a project management technique in which start and finish dates are adjusted based on resource constraints with the goal of balancing demand for resources with the available supply” Prepared by A. Sanchez 21
- 25. Resource loaded schedules Benefits of resource loaded schedules and resource leveling • Determine dates for resources mobilisation and demobilisation • Balanced resources, reducing over allocations or unnecessary overtimes • Validate estimated construction durations • Sanity check of durations, logic and assigned resources Prepared by A. Sanchez 25
- 26. Some factors impacting the baseline schedule Prepared by A. Sanchez 26 PROJECT SPECIFIC FACTORS 1 Relevant design and/or construction codes and specifications 2 Completion date (normal schedule or fast track schedule*) 3 Contractual issues / type of contract / alliances (JV) 4 Payment terms / contract milestones 5 Liquidated damages / consequential damages clauses PROCUREMENT FACTORS 1 Long lead items – equipment or materials (free issue) 2 Freight and transport issues 3 Vendor assistances 4 Warehousing (equipment and material preservation)
- 27. Some factors impacting the baseline schedule Prepared by A. Sanchez 27 CONSTRUCTION ISSUES 1 Location of facility / access to site 2 Weather issues (cold or hot climate, weather windows) 3 Expected productivity of workforce 4 Labor requirements (local content, union, etc.) 5 Labor availability and possible overtime, rosters 6 Establish camp, temporary facilities, site fabrication facilities, laydown areas 7 Location of quarry / concrete batch plant 8 Location of borrow pits 9 Required construction permits 10 Construction method(s) 11 Special safety issues 12 Protection of the completed work
- 28. Contents • The Planning Process • Common planning mistakes • The planning and scheduling process • The construction plan • Productivity rates and construction durations • Resource loaded schedules and resource leveling • Some factors impacting the baseline schedule • Schedule Assurance Review • Schedule quality review • Schedule risk review • Schedule benchmark review • Conclusion 28 Prepared by A. Sanchez