"schedule contingency"

Marcio,
at a high level it is the difference between the Contract Duration and the Project Performance Baseline set by management. In this sense it is a Management Reserve of time equivalent to the cost reserve.

At a lower level it is the additional time built into any schedule to cover for risks and uncertainties inherent in the planning and delivery process.

The appropriate use of some tools & techniques can help in setting these values but it must be a collective project decision rather than a pure planning one.

Peter;

Read what i found.

1. What is your definition of "schedule contingency" ?
A buffer added to a group of schedule activities duration as a form of
preventing time frustrations in the future. The contingency is a reserve the
contractor may eventually use without jeopardizing the end date of the
project. Margin of time for unforeseen conditions, such as imprecise
production rates, rain delays, material shortage, etc.

2. How should "schedule contingency" be treated in a schedule model? As an
activity or as float?
Although I have noticed several schedulers adding extra duration to the
activities, I don’t think this a good procedure, because it tends to show
durations longer than calculated with the adopted production rates, what
makes crews to work in a loose way... The best thing is to add an activity
and the end of a group of similar tasks. For example, in a multi-story
building, I would add an activity called "ceramic tile - buffer" after the
"ceramic tile 10th floor", so that any deviation in this family can be
absorbed by the network.

3. How should "schedule contingency" be managed?
As something that should be avoided.

Could u please guide to find more material about this sibject?

Marcio,
One method of ’Contingency’ I have used to great success in the past and present, is by setting the effort rate for each resource to between 6.5 and 7 hours per day.

E.G.
Activity A has a duration of 10 days, therefore you could assume that if one resource was applied to the activity you could expect that at 8H/d the resource would expend 80 hours over the course of the activity.

However, we could also assume that the resource in question is human and therefore will not perform 8 hours of work in an 8 hour day, due to distractions, etc.

So if we set the future effort rate for the resource at 7H/d and allowed the activity to stretch to accomodate the assumed 80 hours, the duration would now be 11.42 days.

This method could be assumed to be a contingency but I think of it as real life.

Andy

Hi Marcio,

I think this matter is related to "Risk Management" so if u want to read about then i would suggest that u search for books related to "Risk Management".

Thank u all for the responses.

Andrew, thank u for the example.

Karim, i will look for something.

Best regards.

Marcio Eduardo

Critical Chain advocates deal with contingency by adding buffers in specific points along the schedule and sell an add-in to let you do this in P3.
But isn’t it the same as including a hammok activity where we want the buffer, and checking wether it stretches or expands with progress?