SOP: Logical Sequence in Microsoft Project
Objective
Create a schedule where tasks are connected in the correct order so Microsoft Project can automatically calculate dates, identify the Critical Path, and predict project completion accurately.
What is a Logical Sequence?
A Logical Sequence is the correct order in which work must be performed.
Simple Rule:
One task should start only when the required previous task is completed or reaches a specific point.
Without logical sequencing:
❌ Schedule becomes unrealistic
❌ Critical Path becomes incorrect
❌ Resource conflicts increase
❌ Delays cannot be predicted
With logical sequencing:
✅ Accurate schedule
✅ Reliable Critical Path
✅ Easier tracking
✅ Better forecasting
Step 1: Create All Tasks First
Before linking tasks:
Create WBS (Work Breakdown Structure)
List all activities
Define durations
Example:
| ID | Task Name | Duration |
|---|---|---|
| 1 | Site Preparation | 3 Days |
| 2 | Excavation | 5 Days |
| 3 | Footing Work | 4 Days |
| 4 | Column Work | 5 Days |
| 5 | Beam Work | 5 Days |
| 6 | Slab Work | 5 Days |
Do not create relationships yet.
First build the task list completely.
Step 2: Determine Work Flow
Ask:
What must happen before this task can begin?
Construction Example:
Site Preparation
↓
Excavation
↓
Footing
↓
Columns
↓
Beams
↓
Slab
This becomes the logical sequence.
Step 3: Use the Correct Relationship Type
Microsoft Project provides four relationship types.
1. Finish-to-Start (FS)
Most common relationship.
Task B starts after Task A finishes.
Example:
Excavation → Footing
Footing cannot start until excavation is complete.
Relationship:
Task 2 FS Task 3
Example:
| Predecessor | Successor |
|---|---|
| Excavation | Footing |
Approximately 90% of construction schedules use FS.
2. Start-to-Start (SS)
Two tasks start together.
Example:
Concrete Pouring
and
Concrete Testing
Testing starts when pouring starts.
Relationship:
Pouring SS Testing
Use carefully.
3. Finish-to-Finish (FF)
Both tasks finish together.
Example:
Painting
and
Final Cleaning
Cleaning must finish when painting finishes.
Relationship:
Painting FF Cleaning
4. Start-to-Finish (SF)
Rarely used.
Example:
Old Security Shift
cannot finish until
New Security Shift starts.
Relationship:
New Shift SF Old Shift
Use only in special situations.
Step 4: Link Tasks in Microsoft Project
Method 1
Select tasks
Click:
Task Tab → Link Tasks
Shortcut:
Ctrl + Click Tasks
Then click Link
Method 2
Use Predecessors Column
Example:
| ID | Task Name | Predecessor |
|---|---|---|
| 1 | Site Preparation | |
| 2 | Excavation | 1 |
| 3 | Footing | 2 |
| 4 | Column | 3 |
Microsoft Project automatically creates links.
Step 5: Verify the Logic
Ask these questions:
Question 1
Can this task start before its predecessor?
If NO
Keep the relationship.
Question 2
Can these activities overlap?
If YES
Consider SS relationship.
Question 3
Must both tasks finish together?
If YES
Consider FF relationship.
Question 4
Does this relationship reflect real construction practice?
If NO
Adjust it.
Step 6: Check the Network Logic
Go to:
View → Network Diagram
You should see:
Task A
↓
Task B
↓
Task C
↓
Task D
The flow should be easy to understand.
If lines cross excessively:
Review task relationships.
Step 7: Identify Missing Logic
A common mistake:
Tasks without predecessors.
Example:
| Task |
|---|
| Brick Work |
No predecessor.
No successor.
This creates a floating task.
Floating tasks can move anywhere in the schedule.
Fix:
Connect them logically.
Step 8: Avoid Common Mistakes
Mistake 1: Linking Everything
Bad:
Every task linked to every other task.
Result:
Schedule becomes rigid.
Only link tasks that truly depend on each other.
Mistake 2: Using Dates Instead of Logic
Bad:
Manually entering Start Dates.
Result:
Microsoft Project loses scheduling flexibility.
Use relationships instead.
Mistake 3: Missing Predecessors
Bad:
Task has no dependency.
Result:
Unrealistic schedule.
Every major task should have logical connections.
Mistake 4: Wrong Relationship Type
Bad:
Using SS when FS is required.
Result:
Tasks overlap incorrectly.
Always verify construction workflow.
Construction Example
Foundation Phase
| ID | Task | Duration | Predecessor |
|---|---|---|---|
| 1 | Site Preparation | 3d | |
| 2 | Excavation | 5d | 1 |
| 3 | Footing Work | 4d | 2 |
| 4 | Foundation Wall | 4d | 3 |
| 5 | Backfill | 3d | 4 |
| 6 | Ground Slab | 4d | 5 |
Logical flow:
Site Preparation
↓
Excavation
↓
Footing
↓
Foundation Wall
↓
Backfill
↓
Ground Slab
This sequence reflects actual construction operations.
SOP Checklist
Before finalizing your schedule:
☐ All tasks are listed
☐ Durations are entered
☐ Predecessors are assigned
☐ Relationship types are correct
☐ No floating tasks
☐ Network Diagram looks logical
☐ Critical Path is generated correctly
☐ No unnecessary constraints
☐ Schedule reflects real construction workflow
Key Principle
Good Scheduling = Tasks + Durations + Logical Sequence
Without logical sequence, Microsoft Project is only a task list.