Building and Modifying a Cost Breakdown Structure
Mandrel uses a single form (menu call Editing/General Edit) for creating, editing and modifying cost breakdown structures, as shown below.
Adding a Child
Click on the parent to select it, then click on the Add Child button. A new child of that parent will appear in the display. You can give it a name by typing in the Cost Item Name box.
Adding a Sibling
Click on any one of an existing sibling group, then click on the Add Sibling button. A new sibling of that group will appear at the end of that group. You can give it a name by typing in the Cost Item Name box.
If a cost item name is too long to be shown in full in the main display area, you can:
1. Increase the size available for name display by changing to 3-level, 2-level, or single-column display mode;
2. Decrease the font size so as to fit more into the available space;
3. Let the mouse pointer hover over a name for about one second, in which case the full name will be shown below the pointer.
Inserting an Item
Suppose you have a sibling group like this:
and you want to insert a new item, D, between A and B. To do so:
a) Click on any item in the group, then click on Add Sibling. A new item numbered 1.4 will be added, which we will name D. Your CBS will look like this:
b) Ensure that the new item 1.4 is selected, then type 1.2 into the Renumber box and click Go. Your CBS will now have the new item D inserted between A and B. Note that B and C have had to be renumbered to achieve this.
Moving and Deleting Cost Items
You can move and delete individual cost items within/from the breakdown structure. If you do so, be aware that:
a) Mandrel will move/delete not only the item you select but all of its descendants as well, to keep the structure intact;
b) Mandrel will not permit any gaps or duplications in the numbering, so the structure will automatically be renumbered to accommodate any changes you make.
i) Assume you have a CBS that looks somewhat like this, or its equivalent in fixed-digit format:
ii) Click on item 3. to select it, then click on Delete Item. Item 3. will be deleted, and item 4. will automatically be renumbered to close the gap, leaving:
iii) Now delete item 1. This will cause all its descendants (1.1 and 1.1.1) to be deleted as well. The CBS numbering will now start at 2, so Mandrel will automatically renumber everything so the numbering once more starts at 1. Your CBS will now look like this:
i) Using the CBS shown in Deleting Items step (i), move item 1.1 to become item 3.1 (select item 1.1, type 3.1 in the Renumber box, then click on Go). Item 1.1 will now become 3.1 and its descendant (1.1.1) will be moved with it to become 3.1.1:
ii) Now move item 1. to become item 2.1 in the same way. However, this will leave the CBS without an item 1, so as before, Mandrel will automatically renumber everything so the numbering once again starts at 1. In particular, the item you had renumbered as 2.1 ends up as 1.1. Your CBS will now look like this:
Drag-and-drop is deliberately not used here because the automatic renumbering makes it too easy to lose items if you accidentally drop them in the wrong place.