What is a construction baseline schedule?
A construction baseline schedule is the plan everyone agrees to measure progress against. It lists the phases of the job, the work packages inside them, and a planned start and end date for each one. Once it is approved, it becomes the baseline: the fixed reference point that tells you whether the project is on track.
Without a baseline, every progress meeting argues about what the plan was. With one, the question is simpler: is the work done by the agreed date, and if not, when will it finish at today's pace? The dates in the approved plan are the planned dates that later facts are compared with, and the approved plan itself is what planners call the baseline.
What should a baseline schedule contain?
Keep the structure small enough that site staff can report against it. A useful baseline has the same few parts on every job.
- Phases: the large parts of the job, such as a building, a floor group or a construction stage. A phase groups the work that is reported together.
- Work packages or milestones: the pieces of work you report on, each with a short code so a site report can refer to it without doubt. A floor, a section or a facade can each be one work package or milestone.
- A planned start and a planned end for every work package, written as dates rather than as week numbers, so a late item shows up as a date that has passed.
- Key milestones: the handful of dates the client, the bank or the buyers care about, marked so they stand out.
- A progress rule: how the progress of a phase is worked out from its work packages. A plain average is the simplest rule. A weighted average is better when some packages are much larger than others, and the weights must be agreed before work starts.
- An owner and a version number, so anyone can see who approved the baseline and which version is in use.
How do you build a baseline step by step?
Start from the scope, not from the calendar. Walk through what has to be built, phase by phase, and only then add dates. The steps below work for a residential block, a commercial fit out or a civil job.
- Step 1: list the phases in the order the work is done, and give each one a short code.
- Step 2: split each phase into work packages that a site manager can call finished or not finished on a given day.
- Step 3: give every package a planned start and end. When the handover date is fixed, plan backwards from it to see whether the early dates are realistic.
- Step 4: mark the key milestones and agree which dates the client or the bank will see.
- Step 5: agree the progress rule for each phase, and note whether any package carries a larger weight than the others.
- Step 6: review the schedule with the people who will do the work. Their objections are cheaper now than in month four.
- Step 7: approve it, save it as version 1 of the baseline and keep the approval date with the file.
What does a worked example look like?
Say a phase called Frame has three work packages. F1, ground floor walls, is planned from day 1 to day 30. F2, first floor walls, is planned from day 31 to day 60. F3, roof structure, is planned from day 61 to day 80. The baseline says that Frame ends on day 80, and each package carries its own planned end date.
Now say F1 is complete, F2 is half done and F3 has not started. With a plain average, the phase progress is 50%: (100 plus 50 plus 0) divided by 3. If F3 is ten times the size of F1, that average misleads, because the roof hardly moves the number. Give F1 and F2 a weight of 1 and F3 a weight of 10, and the phase reads about 13%: the large part of the work is still ahead, and the number now says so. Choose the rule before the work starts, not after the numbers disappoint.
Where do dependencies and the critical path fit?
A list of dates does not show which work must finish before another can start. Planning tools handle this with dependencies and a critical path: the chain of linked tasks that decides the finish date. If the roof structure cannot start until the walls are up, the planner must record that link, or a late wall will look harmless in a plain list.
Reperline does not calculate dependencies or the critical path, and it has no Gantt editor. Keep the predecessor links in the planning tool you already use. Reperline takes the approved dates as the baseline and shows whether each dated package is on pace and where it is heading. The planning tool owns the logic; Reperline owns the facts and the warnings.
How does the template fit in?
The baseline schedule template on this site is a free XLSX file for building the baseline. It puts phases, work packages, planned dates and progress in one table, and works out a forecast end date and the days of slip from the actual pace. It is a starting point for the list, not a planning tool with its own logic.
Reperline does not take a schedule from the XLSX file. It imports a schedule PDF. Once the baseline is agreed, export it to PDF from your planning tool and let the owner upload it in the project settings. The import shows every work package and date as a preview, and nothing is applied until the owner confirms it. A milestone that does not read correctly can be added by hand, and on Project Pro the team moves your schedule in for you. See the schedule module for the detail.
How do you keep the baseline useful once work starts?
The baseline should change only by a decision, and every change should leave a trace. When a date moves, record a new version with the reason, and keep the original dates visible beside the new ones. Never overwrite a planned date to make a late item look on time. The words planners use for this are slippage and variance.
Progress facts drive the forecast. A simple way to read a milestone is the linear forecast: the time spent so far, divided by the share of work done, gives the time it will need. Say a milestone started 20 days ago and is 40% done. At that pace it needs 50 days in total, so it is forecast to finish 30 days from today. That is a forecast, not a promise. If the crew doubles next week, the number changes, and it should.
How does Reperline handle this?
Reperline keeps the approved dates as the planned dates of the schedule module and compares them with facts from site every day. The forecast end of a milestone is the linear pace described above. A milestone with no progress gets no forecast, so nothing is invented. A milestone whose planned start has passed with no fact at all is marked as missing data, so silence never looks like good news.
Three rules watch the schedule. A milestone is overdue when its planned date has passed and the work is not finished, and it is high priority after 14 days. A milestone is forecast behind plan when, at today's pace, it ends more than 7 days after its planned date. An active phase is silent when it has had no new fact for 7 days. The owner can change these thresholds for the whole company or for one project. The signals module explains how the warnings reach people. Reperline does not replace the software your planners use to build a schedule; it takes the baseline as the reference and tells you how far reality is from it. The plans are on the pricing page.