When to rebaseline a schedule

thats an open ended question

1. set your parameter l a lot of time its when the project slips 21 working days. The owner may ask you to revise it whne it slisp this must you you have slpped this much and are not gaing any ground on the schedule and the float remains negative.

You may decide to pull this trigger earlier by setting your own threshold say 15 days negative.  Yes I would set the threshold at the planning stage so that you ar enot aruging about it later in the heat of battle. 

2. If you have a major change of direction such as a major change in sequence. i.e. the schedule shows you working in a east to west direction but things have happend that now force you to work  in a west to east or a north to south direction.

or you were going to build out the building from the top floors down now you have decided to build out the buidling from the ground level up to the roof. 

Its a subjective matter and there is no hard-and-fast rule on how/when to do such.

In my opinion, poor performance is not a valid reason for re-baselining. Generally, re-baselining should only occur when a change in scope requires a change in the methodology and resultant cost or schedule required to deliver that change.

Thank you Santosh.

That is true. We cannot just rebaseline because of poor performance. The reason I had presented my question the way I did is that I had witnessed that in one of the projects I was involved in; the contractor was two months behind schedule and had only completed 30% of the works opposed to the 80% that the baseline suggested. At the time I asked but couldn't be given a definite threshold we were observing..., just that it was obvious that the contractor would never catch up. I truely value your input and again thank you for helping me out.

Thanks Zoltan,

I like the idea of setting a threshold at the beginning to ensure that we're in alignment throughout the project. I just haven't witnessed that being practiced in my short career. It would really clear a lot of confusion. I also agree that the schedule should definitely be rebaselined in case of a significant change to the scope of methods of execution.

Hi Kabu

I agree with both Zoltan and Santosh's comments there is no hard and fast rule here.  In my experience it really does depend on the project and the commercials behind the project.  If there are liquidated damages in the contract and large sums of money involved (Mega projects), the client will say "never" the baseline is the baseline and the contractor is commercially obliged to meet the contractual completion dates.  It is then up to the contractor to prove excusable delays were caused by the client or can be claimed via contractual clauses.  If you are involved in a project like this you need to really have your ducks in a row and be able to record and explain what has casued every slippage.  If it goes to arbitration you will have a whole team of lawyers asking you questions and you will be expected to know. 

But there is a point where a baseline becomes pointless.  Its hard to measure progress and continually motivate a team to hit targets or stay on track if they are a long way behind schedule.  It can really become demotivating to a team.  In this case I would say a rebaseline would be generally agreed by all parties so that you can meaningfully measure progress each week and work out a recovery plan for small slippages.  Planners should be heavily engaged with the construction manager and Project manager and they will direct you when the time is right to rebaseline based on your input and their desire to get the project "moving".

Kind Regards

Sterling