Gantt Chart

Auto-draw a construction schedule Gantt chart from an Excel data table — task name, start date, duration, % complete, predecessor, resources.

Open the sample (fastest)

DVD Cons → group Schedule → Schedule Template (template icon).

Excel opens template GanttChart.xlsx containing:

• Sheet HuongDan — column reference guide.
• Sheet Input — sample data table.
• Sheet MHC.VP_Schedule_Template — pre-drawn Gantt chart.
• Sheet OPL.HY_Schedule_Sample — real-project sample.

Copy/edit the Input table → click Draw Schedule → chart refreshes.

Input table structure

Column	Name	Description
A	No.	Auto-numbered (1, 1.1, 1.1.1, ...)
B	Code	Task code (e.g. MHC1130)
C	Task name	Work description
D	Predecessor	Predecessor code + offset (e.g. MHC1120FS+2)
E	Duration	Days (integer)
F	Start date	Auto-computed from predecessor or entered manually
G	Finish date	Auto-computed (Start + Duration - 1)
H	% Complete	0-100 (renders progress bar inside the task bar)
I	Resource	Headcount (used in the Resource Histogram)

Columns J+ form the Gantt drawing area (1 column = 1 day, hidden/shown depending on zoom).

Draw the chart

DVD Cons → group Schedule → click Draw Schedule.

The code reads the Input table → draws:

• Task bars (green) for each row — from Start to Finish.
• Summary bars (black) for rows with sub-tasks beneath.
• Progress bars (purple) overlaid on task bars — length per %.
• Critical path (red) for tasks with no slack.
• Milestones (red diamond) for tasks with Duration = 0.

Schedule Settings

DVD Cons → group Schedule → Schedule Settings.

Option	Behavior
Draw Resource Histogram	Show a bar chart below the Gantt — each day = total active headcount.
Show progress bar (%)	Draw the purple bar over the task bar.
Show start / finish dates	Label dd/MM/yyyy on the left + right of each bar.
Show duration above bar	Label N days above each bar.
Date format	dd/MM/yyyy / dd/MM / MM/yyyy.

Click Save settings — saved per-user in registry, applies to all workbooks.

Auto-calc toggle

DVD Cons → group Schedule → toggle Auto Calc.

• ON (default): editing Duration / Predecessor / Start triggers Start/End recompute → chart redraws.
• OFF: you enter Start/End manually, the addin doesn't intervene.

Turn OFF when fine-tuning tasks that don't follow standard predecessor logic.

Predecessor syntax

Syntax in column D:

MHC1120        — Finish-to-Start (FS), offset = 0 (default)
MHC1120FS      — FS, offset = 0
MHC1120FS+2    — FS, offset = +2 days (start 2 days after predecessor finishes)
MHC1120FS-1    — FS, offset = -1 day (overlap by 1 day)
MHC1120SS      — Start-to-Start (start together)
MHC1120FF      — Finish-to-Finish (finish together)
MHC1120SF      — Start-to-Finish (rare)
MHC1100,MHC1110FS+1   — multiple predecessors, comma-separated

Relationship types:

• FS (Finish-to-Start) — most common: B starts after A finishes.
• SS (Start-to-Start) — B starts at the same time as A.
• FF (Finish-to-Finish) — B finishes at the same time as A.
• SF (Start-to-Finish) — B finishes when A starts.

Schedule Template

DVD Cons → Schedule Template → opens a fresh template workbook with:

• MHC sample data (Mehrer Hill Construction — office project).
• OPL sample data (Office Park Long Bien — extension project).
• Mucluc config sheet.

Don't edit the original template

The template file lives at C:\DVDAddin\Template\GanttChart.xlsx (read-only). Clicking "Schedule Template" opens a copy in a new workbook — edit freely and save anywhere.

License gating

Command	Free	Activated/Trial
Schedule Template (open template)	✓	✓
Auto Calc (toggle)	✓	✓
Schedule Settings	✓	✓
Draw Schedule (gen Gantt)	✗	✓

The most important command (Draw Schedule) requires a license. Auxiliary commands (open template, config, toggle) are free.

Troubleshooting

Chart shows wrong dates

• Are Start/End cells formatted as Date or Text? Must be Date.
• Predecessor references the correct task code in column B?
• Column E Duration is an integer, not text.

Task bars have no color / are too thin

• Row height too small. Auto-fit row height (Home → Format → AutoFit Row Height).
• Check Excel zoom (Ctrl + scroll wheel).

Resource Histogram is empty

• Column I (Resource) must be a number.
• In Schedule Settings → tick "Draw Resource Histogram".
• Click Draw Schedule again after changing the setting.

Critical path (red) shows incorrect tasks

• Critical path is computed via CPM (Critical Path Method). Needs full predecessor + accurate duration.
• Any task with circular predecessors → undefined behavior.

Related

• Cutting Optimizer — rebar cut optimization, same DVD Cons tab.
• Numbering — auto-number 1, 1.1, 1.1.1 for column A of the Input table.