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procedure 18 1 types of schedules v 2 oct06 page 1 bureau of engineering project delivery manual chapter 18 construction schedule control procedure 18 1 types of schedules version 1 june 2003 version 2 october 2006 latest revision purpose the type of construction schedule utilized depends on the specific project requirements the purpose of this section is to provide guidelines for selecting the appropriate construction schedule specification to fit the project prior to bid the following goals have been identified for project scheduling 1 to provide an overall status report 2 to coordinate a project s time frame with other contracts and the client s needs 3 to permit close monitoring of the contractor s progress 4 to provide a basis for monitoring the potential schedule impact of change orders and claims 5 to provide a basis for remedial action as necessary 6 to provide a basis for payment when the bureau of contract administration agrees to use the cost loaded schedule references links boe master specification division 01 gr section 01321 contractor s construction schedule and reports standard specifications for public works construction green book section 6 prosecution progress and acceptance of the work responsibilities project manager pm the pm is responsible for selecting the appropriate construction schedule specification and establishing the overall contract duration for the project the pm should consult with the construction manager when making the selection on small projects the pm may defer to the project award and control page 2 procedure 18 1 types of schedules v 2 oct06 bureau of engineering project delivery manual division to determine the contract duration the pm also must determine whether the schedule duration for the project will be calendar day or working day calendar day schedules are appropriate for larger more complex projects for smaller simpler green book projects where submittal approval and procurement activities are less likely to be critical a working day schedule makes more sense historically the construction manager has been responsible for schedule control of calendar day projects on smaller green book projects the pm has the discretion to defer the schedule review and tracking responsibility to the lead inspector construction manager cm the cm provides guidelines to the contractor for the development of the construction schedule reviews and accepts the project s baseline schedule reviews the monthly schedule update submittal for acceptance and provides comments to the schedule submittal contractor the contractor is responsible for the development of the construction schedule as required by the contract specifications whenever the short medium or long versions of the schedule specification are used the contractor is responsible for updating the schedule on a monthly basis to reflect the actual status of the project progress changes etc each week the contractor is also responsible for producing a three week progress schedule listing the activities completed and in progress for the previous week and the activities scheduled for the next two weeks the activity designation description and id number shall be consistent with the project s baseline construction schedule when the green book version of the schedule is used the contractor shall revise and update the schedule as required by the inspector lead inspector li on working day projects usually using the green book schedule version the li has responsibility for tracking the schedule progress the pm may also defer the initial schedule review responsibility to the li the li must communicate with the pm and cm regarding the contractor s performance and schedule delays the pm needs to keep the project stakeholders informed regarding schedule progress and the cm needs to write any change orders to cover justified time extensions attachments links 18 1 1 green book version schedule sample 18 1 2 short version schedule sample 18 1 3 medium version schedule sample 18 1 4 long version schedule sample 18 1 5 three week progress schedule sample procedure 18 1 types of schedules v 2 oct06 page 3 bureau of engineering project delivery manual procedure in this procedure the pm and the cm shall be familiar with the 4 schedule versions utilized by the city 1 green book and 3 from the master specifications gr section 01321 this procedure also includes the cm s responsibilities in the pre construction scheduling conference schedule options there are 3 different schedule specification versions in the master specifications see reference documents which are generally based on project size and complexity also there is a green book version which is typically used for small noncomplex projects the three schedule versions in the master specifications are used for calendar day projects while the green book version is more suitable for working day projects the pm must select the schedule specification version described below that is the most appropriate for the project and edit that version to include project specific requirements the following are brief summaries of the scheduling requirements for the green book and the 3 schedule specification versions in the master specifications green book version this version is used for straightforward sewer stormdrain or street projects with a construction value less than approximately 2 000 000 the schedule requirements are in section 6 of the green book this version is a bar graph or tabulation with no logic ties between the schedule activities short version the short version is used for small noncomplex projects with estimated project costs of less than 0 5 million or larger projects that require few interfaces and minimal coordination with other projects the short version schedule specification allows the contractor to submit either a critical path method cpm network or a detailed bar chart schedule this is the only master specification version that does not mandate a cpm schedule or the use of scheduling software medium version the medium version is used for small noncomplex projects with estimated project costs of 0 5 million to 3 million that require few interfaces and minimal coordination with other projects the medium version schedule specification requires the contractor to submit a detailed cpm schedule using specialized software primavera project planner p3 or suretrak long version the long version is used for projects with estimated project costs greater than 3 million or smaller size projects with a high degree of complexity or interfaces with other projects the long version schedule specification has several upgrade options that are used for large complicated projects which may require 2 to 3 months to arrive at an approved project schedule this version requires the contractor s construction schedule to be a cpm schedule page 4 procedure 18 1 types of schedules v 2 oct06 bureau of engineering project delivery manual the contractor is to use primavera project planner the latest version to develop the schedule for the short medium and long versions described above the cost to perform the work activity is to be noted for each activity of the schedule on a tabular listing the sum of the costs assigned to all activities must be equal to the contract value three week progress schedule the short medium and long schedule versions require the contractor to also prepare three week progress schedules three week progress schedules are bar graph schedules that show the work performed in the previous week and the work the contractor is planning to do in the next two weeks the contractor should bring the updated three week progress schedule to the weekly construction meetings each bar on the schedule should include the related activity identification number from the project s baseline schedule the one week history should be reviewed for accuracy at the weekly meeting so it can be used as a basis for the monthly update of the project schedule the two week look ahead can be used to give the inspector advance notice of the work they need to inspect in the immediate future and enable the cm to establish priorities for processing rfi s change orders plan clarifications etc schedule presentation the types of schedules utilized by the city are presented as either a bar chart or a time scaled logic diagram which is better known as a critical path method schedule the two ways to present a schedule are described below bar charts most bar charts are kept rather simple in terms of content a bar chart is generally comprised of horizontal bars with a time scale at the top the bars represent the component of work items to be performed bars are drawn to graphically represent the span of time necessary to accomplish each work item a bar chart is also known as a gantt chart bar chart schedules by definition do not indicate the successor or predecessor relationship of one bar to another critical path method cpm a cpm time scaled logic diagram is a graphic presentation of the planned sequence of activities that show the interrelationships and interdependencies of the activities comprising a project the critical path contains a series of related activities which must be performed in sequence and whose cumulative duration is the longest the cpm can be used for any of the 3 master specification scheduling versions described above pre construction scheduling conference after the contract is awarded the cm needs to hold a pre construction scheduling conference with the contractor s pm and construction scheduler within 7 calendar days after notice to proceed to commence development of the required project schedule at this meeting the scheduling requirements as they apply to the procedure 18 1 types of schedules v 2 oct06 page 5 bureau of engineering project delivery manual contract will be reviewed with the contractor the cm shall be prepared to review and discuss the methodology and requirements for the schedule sequence of operations cost manpower and equipment loading methodology establishing construction duration and milestones there are a few empirical rules the pm should keep in mind while customizing the project schedule requirements unless you have a simple perfectly designed project murphy s law is going to take over at some point for one reason or another the project schedule will slip expect the project schedule to slip at least 3 months per year of planned construction time if the pm has made commitments to the owner neighbors or have a subsequent contract that will be impacted by the current project the best tool to gain some control over meeting the commitments is to establish the appropriate project milestones there are four types of milestones typically used 1 the contractor can t start work on a certain portion of the project until a spe