Construction schedule and Gantt chart with the critical path calculated for you

How do you build a schedule in Santix?

A Santix schedule is a set of tasks, the links between them and milestones. Once they are in, the critical path method (CPM) gives every task its early and late dates and its total and free float. Durations are in working days. You choose the working week when creating the project: Monday to Saturday (the default, since most Turkish sites work Saturdays) or Monday to Friday.

1. Open "İş programı" under "Proje" in the sidebar (the app is in Turkish). Start with "Görev ekle" (add task) or bring in a file with "İçe aktar" (import).
2. Add tasks with durations, such as ground floor plastering, 8 days, and ground floor screed, 4 days.
3. Give each task a WBS code, parent, person responsible, subcontractor and trade where useful. Parent tasks roll up their children.
4. Link tasks: choose the type (finish-to-start, start-to-start, finish-to-finish, start-to-finish) and any lag in working days.
5. Enter permits, structural completion or handover as milestones.
6. When the programme is agreed, save the baseline. Every later slip is shown against it.

If a new link would create a loop, Santix refuses it with a cycle warning, so the error is caught when you type it rather than when the calculation fails.

What does a task hold?

Status labels read planned, on plan, ahead, late, overdue and done, with a separate critical path tag.

Which dependency types are supported?

All four, each with a lag in working days; a negative lag pulls the next task forward (a lead).

How is the critical path calculated? A worked example

The critical path is the chain of tasks with zero total float: a one-day slip there moves the finish by a day. This simplified example comes from the ground floor finishes of Santix's sample project, Ataşehir Blok B (ATB-02); figures are working days.

The floor finishes in 28 working days. The electrician has 14 days of float and can start a week late without moving anything; a tiler two days late moves painting and handover by two days. When a critical task falls behind, a banner above the Gantt reads "Kritik yolda geciken N iş" (N late tasks on the critical path). Our critical path guide works through a longer example by hand.

Baseline and delay penalty estimate

Saving the baseline stores each task's finish date. A task counts as late when its planned finish has passed without completion or its forecast finish is behind the baseline, and the task screen shows the variance in working days.

If the task is linked to a subcontract with a daily delay penalty, Santix shows a penalty estimate in calendar days against the contract end date (or the baseline when the contract has none), capped at the contract limit. For a ₺1.200.000 tiling contract at 1 per mille a day with a 10 % cap, five days late shows ₺6.000. It is an estimate; you apply any penalty in the progress payment yourself. See contract templates.

How do imports work?

Santix imports MS Project files saved as XML (MSPDI) and Primavera P6 XER exports. Tasks and links come across, the WBS is kept and durations are converted to the project's working calendar.

1. Save as XML in MS Project, or export XER from Primavera P6.
2. Open "İçe aktar" in the schedule and pick the file.
3. Check the preview, then import. Tasks are written on the device first and sync when online.
4. Assign people and subcontractors, then save the baseline.

MPP files do not open directly; save them as XML first. Where a file gives durations in hours without a working day length, 8 hours a day is assumed.

Where does progress come from?

Crews mark finished areas on the drawing per room and work item; Santix converts that to a percentage (tiling by net floor area, painting by wall area) and rolls it up to the linked task. Moving the slider switches the task to manual progress until you choose to calculate from site again. See progress tracking and room data sheets.

iPad, iPhone and calendar views

The iPad Gantt shows bars, dependency arrows, a today line, the critical path and the baseline, with day, week and month zoom and fit to screen. The list works on any device with comfortable or compact rows, and the calendar shows what runs each week. Filters are the same everywhere: all, today, this week, late and critical path.

How do you run the weekly site meeting from it?

1. Start with the critical path filter. Every day lost there is a day added to handover.
2. Switch to late tasks and check whether each new date still fits inside the task's float.
3. Use this week to walk through what starts next and which subcontractor owns it.
4. Check progress marked on the drawing, and the penalty estimate on late contracted tasks.

Anything the meeting raises can be opened as a pin on the drawing; see drawing markup.

Who can see and change the schedule?

Project managers, site managers and field engineers add and edit tasks. Architects and viewers can read. Subcontractors see only tasks assigned to them or their company and can update their own progress. Owners have full access. See the project manager role.

What the schedule does not do

• No resource loading or levelling: crew and plant numbers do not move the programme.
• No per-task calendars; the project uses one working calendar, and there is no screen yet for entering public holidays.
• No MPP import and no export back to MS Project or XER.
• Cost and cash flow live in progress payments and budget, not here.

Why not a bar chart in Excel?

A spreadsheet bar chart is a picture: when one task slips, the rest do not move and nothing tells you which tasks are critical. In Santix the links carry the change through the whole chain, variance against the baseline is calculated, and subcontractors see only their own tasks. The full comparison is on Santix instead of Excel and WhatsApp; short definitions are in the construction glossary.