Reviewing CPM schedules using Primavera’s Planner/Scheduler 5.0 (P3ec) Presented by Don McNatty Agenda Reviewing CPM schedules A simple process for avoiding headaches… What is a CPM schedule? Why require it? Why get it electronically? What should your specification ask for? The Key elements of the CPM submittal A process for reviewing schedules with P3ec Tools for reviewing schedules The importance of perspective Questions Reviewing CPM Schedules What is a CPM schedule? Is it too complex? Critical Path Method The “critical path” is the longest path of activities through a schedule that determines the schedule completion date. A delay to any activity on the “critical path” will impact the completion date of the schedule. A “CPM” schedule can be used to identify “what’s important” at any point in time Critical Path Method (CPM) CPM Calculations Forward Pass Calculates the Earliest Dates (Start Day + Duration – 1) 1 5 A 5 6 X11 20 XX25 C 15 1 10 B 10 CPM Calculations Backward Pass Calculates the Latest Dates (Finish Day - Duration + 1) 1 5 A 5 6 10 11 25 C 15 11 25 1 10 B 10 1 10 CPM Calculations Total Float Is the Difference between the Late and Early Dates (TF = LF - EF) 1 5 A 5 TF=5 6 10 11 25 C 15 11 TF=0 25 1 10 Critical Path = B, C B 10 1 TF=0 10 Negative Float Late Dates are Earlier than your Early Dates Caused by a constraint 1 5 A 5 TF=0 1 5 11 25 C 15 FNL=20 6 TF=-5 20 1 10 Critical Path = B, C B 10 -4 TF=-5 5 Calendars convert work days to dates Reviewing CPM Schedules Why Require it? What is the benefit of a CPM schedule? Do you want to be able to control your project? Do you want an “early warning” of potential problems? Do you want to be able to identify where to focus your efforts to avoid or solve problems? A good CPM tells the project manager what has to be done, where, when and by who? Define activities based on WBS/OBS Matrix What does a good (useful) project schedule provide? What has to be done? Where does it have to happen? 4 Who is responsible for doing it? When does it have to happen? When a project manager has this information, the pm has the basis for “control” Reviewing CPM Schedules Why Require it electronically? Do I still need the paper? The schedule is a tool. (it may also be evidence). Get all evidence in hardcopy first (PDF?) Get the electronic version so you can analyze it Comparing the electronic versions between each update can give you a perspective beyond the hardcopy Reviewing CPM Schedules Why Require it electronically? Do I still need the paper? Each monthly update provides a complete audit trail, should you ever need it. Having the electronic copy also let’s you do “what-if” scenarios. You still should get the “hardcopy” just in case the quality of the electronic copy is poor. Reviewing CPM Schedules What should your spec’s ask for? Schedule submittal specifications are usually Section 01310 Make it the contractors responsibility to submit the schedule in a format that can be imported to P3ec 5.0 without variance. P3ec imports P3, Suretrak and MS Project files, but depending on how the scheduler uses them, there can be conversion issues – make this the contractors problem, not yours. P3ec is a free upgrade to P3 users. Primavera Contractor costs the same as Suretrak and MS Project. Reviewing CPM Schedules What should your spec’s ask for? Schedule submittal specifications are usually Section 01310 Most Important! Insist on a written Narrative that clearly identifies the presence and reason for: Lags, constraints, actuals that have changed since last update, durations (other than remaining) that have changed since last update, added and deleted activities, relationships, codes, descriptions, values… Reviewing CPM Schedules What should your spec’s ask for? Schedule submittal specifications are usually Section 01310 If you are referencing the contractors schedule to update your Master schedule, then you should specify Data Dates in your contract to ensure alignment of data You can import the contractors detailed schedule to P3ec without importing it to your “master schedule” The “master schedule” should be at a summary level What is the “Data Date” The remaining schedule starts on the Data Date… 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Data Date (Day 17) is at the first day of the remaining schedule Completed Work Remaining Work Reviewing CPM Schedules What should your spec’s ask for? Schedule submittal specifications are usually Section 01310 If you are referencing the contractors schedule in your Master schedule, you should specify the lowest level of your Master Schedule to drive the highest level of the contractor’s schedule. This is a good application for a “schedule of values” so you can align $$$ with your schedule Only enough detail for your level of “control” or “knowledge” Level 1 - Project Project 1 Project 2 Project 3 1 Activity per project Master Level 2 - Phases Design Procure Construction Schedule 3-5 Activity’s per project Level 3 - WorkPackages Site Prep Foundation Slab Steel Also called the “CM” schedule. 25 – 35 activities per project. Level 4 - Contractor CPM Schedule Form Loc 1 Mesh Loc 1 Pour Loc 1 As much detail as needed to communicate W4 Reviewing CPM Schedules Key elements of CPM submittal? Remember Jim Zack’s “Scheduling Game # 1” (don’t do it…) Letter of Transmittal “Hardcopy” Reports – “PDF” is hardcopy… Electronic copy of Schedule Schedule Narrative Schedule Graphic Reviewing CPM Schedules Key elements of CPM submittal? “In a format that can be imported to P3ec 5.0 without variance from hardcopy…” Electronic copy of Schedule P3ec (XER) format Primavera Contractor 4.1 and higher Recommendation: DO NOT convert submittal files, do not accept Suretrak files that are not in a P3 format. Do not accept & convert MS Project files – they calculate differently than P3. Do not accept files that will not open. Reviewing CPM Schedules Key elements of CPM submittal? Insist on a complete narrative or you could be responsible for what you don’t know that you didn’t know… Schedule Narrative Baseline (Initial Submittal) should identify and justify all lags, constraints and hammocks & preferential logic Updates should identify all changes from previous submittal The Narrative is to the Schedule as the Specifications are to the Drawings (Drawings are incomplete without specs, Schedule is incomplete without Narrative…) Reviewing CPM Schedules Key elements of CPM submittal? The schedule may be “evidence”, clearly identify… Letter of Transmittal Date Project Data date Attachments Reviewing CPM Schedules Key elements of CPM submittal? The electronic schedule file should say the same thing as the hardcopy Hardcopy Reports Tabular activity list with Early/Late dates, durations, float Predecessor/Successor Report (only place you see lags) If cost loaded, activities with budgets, this period, to date, remaining and at completion cost (billing…) Tabular activity list Predecessor/Successor Report Cost Loading Report Review Narrative Reviewing CPM Graphics Key elements of CPM submittal? Like the tabular report, the bar chart has to say the same thing as the electronic file Schedule Graphic A simple bar chart with logic Include columns for activity ID, description, early dates, original and remaining duration, percent complete and total float Highlight progress (Blue) based on Pct, critical path (Red) based on Longest Path, Baseline (Yellow) under current bar CPM Bar Chart Reviewing CPM Schedules A process for reviewing schedules Load, test, analyze, evaluate… Baselines Establish a good starting point and foundation Updates Be aware of what changes from update to update Time Impact Analysis Be aware of the impacts of changes as they happen BASELINE REVIEW Keep your objectives clear Quality Control vs. Audit Establish a realistic and useable schedule Look at bar chart last Recalc & diagnostics Check settings & dictionaries Evaluate data integrity Confirm compliance Validate buildability Baseline Review Confirm Submittal Review Baseline Narrative Recalculate & Copy and compare, run Diagnostics Scheduling-Leveling Report Schedule Options, User Check Settings Preferences, Calendars, Admin & Dictionaries Preferences Revise & Resubmit Calendars, Descriptions, Durations, Evaluate Data Relationships, Lags, Float, Critical Integrity Paths, Cost/Resource allocation Confirm Scope, Constraints, Milestones, Compliance Notebooks Work Sequence, Staging, Site Validate Buildability Logistics, Constructability Accepted, Accepted-As- Acceptance Noted or Rejected Recalculate & Diagnostics Import without calculating Make a copy & recalculate Run a ClaimDigger Report Any variance with uncalculated schedule Means the schedule was changed after calculating and before making a backup file Then run Scheduling-Leveling Report Diagnostics Import without calculating Make a copy and recalculate • Use the EPS to isolate contractor schedules from your master schedule • Use the File/Import command to load the contractors schedule into P3ec • Making a copy of the schedule is as easy as Edit/Copy and Paste • Open the copied project and recalculate (use F9) • Use ClaimDigger to check for any variances • Any Variances means the project was modified in some way after it’s last calculation Run ClaimDigger Report Variances with original submittal? • Any Variances means the project was modified in some way after it’s last calculation • This may cause the electronic data to vary from the “hardcopy” in the submittal • This is usually just an honest mistake made by a scheduler trying to meet a deadline • But it means that the schedule file needs to be resubmitted Scheduling-Leveling Report • When you schedule the project, check the box to log statistics to a file • First time using P3ec, you have to edit the filename so it prints on your local computer • Store each submittal in a folder with the submittal name on it Scheduling-Leveling Report Look up the activity… Data date says May 2nd… The Constraint is unsatisfied because no early start can be before the data date Start On constraint says May 1st… Check Settings & dictionaries Schedule Options User Preferences Calendars Admin Preferences Schedule Options Leveling not recommended except for the contractor to use it Recalculation not recommended as an analysis tool to determine because it may change coststhe Retained logic is need for “preferential logic” default. Progress Override will ignore logic you previously accepted (see next slide) Calculation Options User Preferences P3ec default may show time Calendars Use the “Collapse All” command on the View Menu to summarize the calendar list Calendars Calendars If the calendars are different, for example this one doesn’t have holidays in it, do you think that will cause schedule dates to change? Admin Preferences Evaluate data integrity Calendar Assignments Descriptions Durations Relationships, Lags Float, Critical Path(s) Cost or Resource Loading Confirm Compliance Scope of Work Constraints Milestones Notebooks Validate Buildability Work Sequences Staging Site Logistics Constructability Baseline Review Questions Can a schedule be reviewed from just the bar chart? Why do we recalculate the schedule? Why are different Calendars utilized? Why use a standard approach to Descriptions? Why should we check Lags? Why should we document Constraints? Why do we need “hardcopy” along with electronic? What can the resource histogram tell me? Whay use is the cash flow loading report? Reviewing CPM Schedules A process for reviewing schedules Load, test, compare, evaluate… A few simple steps and comparisons You don’t have to be a scheduler to identify what has changed, see if it is addressed in the Narrative, and decide if you agree with why it changed Update Review Confirm Submittal Review Update Narrative Recalculate & Baseline Comparisons, Perform Comparison ClaimDigger Report Diagnostics Actual Dates, Percent Check Settings Validate Complete, Rem Durations & Dictionaries Progress Out-Of-Sequence Progress Evaluate Data Analyze Start/Finish Dates, Integrity Variances Changes in Durations Actual vs. Original Durations, Confirm Identify Current vs. Baseline or Compliance Trends Previous update Float Validate Measure Current vs. Planned Pct Compl, Buildability Performance Earned Value (Res/Cost) Accepted, Accepted-As- Acceptance Noted or Rejected Track Key Statistics BASELINE FIRST SECOND THIRD FOURTH CATEGORY SCHEDULE UPDATE UPDATE UPDATE UPDATE Total No. of Activities 321 325 316 332 336 % Critical Activities 32% 44% 42% 38% -- Critical Path Total Float 0 -10 -8 -4 -- Total % Complete 0% 20% 45% 80% 100% Project Completion Date 3/01/02 3/15/02 3/13/02 3/07/02 3/06/02 Total Resource Qty At Compl 11,560 hrs 11,640 hrs 11,720 hrs 11,740 hrs 11,710 hrs Total Costs At Completion $1,250,000 $1,350,000 $1,400,000 $1,450,000 $1,375,000 Update Review Questions What two files should we set as Targets so we can display/compare dates? How do you compare a schedule if you don’t have one of the utilities? Why isn’t it a good idea to change Actv ID numbers? Can the Critical Path change? Why do we analyze trends? In a resc/cost loaded schedule, what would be a good way to measure performance? Examples of use on a single project Presented by Craig Olsen at a recent UG meeting Craig is VP in Construction Services Group at URS and a Certified Primavera Trainer Imported schedules from multiple sources P3, Suretrak, Excel Maintained a summary master schedule for the overall project Referenced contractors schedules for updating master Example show how to focus on one specific group of activities – concrete pours Projects Screen Summary By P3 File Summary By File & Area Summary By Area & File Summary of Pours Detail of selected Pours Detail by Activity by File Reviewing CPM Schedules The importance of “perspective” Does the schedule reflect how the work is being done? The higher the percentage of “out of sequence” work the less the schedule is being followed If changes don’t make sense, can’t or aren’t explained…, the schedule is going out of control The Narrative is probably more important than the schedule – it’s in english… Schedule Review Course Full course covers two days Includes review of CPM fundamentals Detailed, hands on use of P3ec for Baseline review Update review Time Impact Analysis DRMcNatty is a Certified Primavera Trainer and Authorized Representative Have focused on implementing Primavera tools for almost 20 years Questions?