You have described the inherent problem of using windows analysis and why I would never use it.
Let us start with the three "Building Blocks" required for a Time Impact Analysis (UK Terminology)
1. If the project is nearing completion then you have the full as built record and can reconstruct an as built programme in as much detail as possible.
2. You are in the process of setting up a viable baseline programme.
3. You have not mentioned an Events Schedule but this needs to be developed - including both Employer and Contractor delays.
Now when you have all three in place you can start the Time Impact Analysis by setting up the event schedule in Chronological Order of Delay Impact.
Then Impact the events one by one starting with the earliest.
There will be four possible results in respect of the Baseline compared to the As Built.
1. The Baseline Start is later than the impact date so no effect at all.
2. The Impacted Task falls short of the As Built in which case something else caused a further delay.
3. The Impacted Task lays over the the As Built in which case the cause and effect can be said to be proven within the "Bounds of Probability"
4. The Impacted Task overshoots the As Built in which case some sort of Mitigation must have taken place to adjust the baseline programme.
If you know what adjustments were made to the logic or resource levels then apply them at this stage - if not you will have to make your own adjustments based on experience of what a contractor would have done in the circumstances.
Always keep in mind that the results are entirely theoretical and do not necessarily reflect what actually happened.
All of the above is described - with working examples - in my book "Basic Priciples of Delay Analysis" now available for download from my website:
Member for
19 years 10 monthsHi John You have described
Hi John
You have described the inherent problem of using windows analysis and why I would never use it.
Let us start with the three "Building Blocks" required for a Time Impact Analysis (UK Terminology)
1. If the project is nearing completion then you have the full as built record and can reconstruct an as built programme in as much detail as possible.
2. You are in the process of setting up a viable baseline programme.
3. You have not mentioned an Events Schedule but this needs to be developed - including both Employer and Contractor delays.
Now when you have all three in place you can start the Time Impact Analysis by setting up the event schedule in Chronological Order of Delay Impact.
Then Impact the events one by one starting with the earliest.
There will be four possible results in respect of the Baseline compared to the As Built.
1. The Baseline Start is later than the impact date so no effect at all.
2. The Impacted Task falls short of the As Built in which case something else caused a further delay.
3. The Impacted Task lays over the the As Built in which case the cause and effect can be said to be proven within the "Bounds of Probability"
4. The Impacted Task overshoots the As Built in which case some sort of Mitigation must have taken place to adjust the baseline programme.
If you know what adjustments were made to the logic or resource levels then apply them at this stage - if not you will have to make your own adjustments based on experience of what a contractor would have done in the circumstances.
Always keep in mind that the results are entirely theoretical and do not necessarily reflect what actually happened.
All of the above is described - with working examples - in my book "Basic Priciples of Delay Analysis" now available for download from my website:
www.expertdelayanalysis.com
£25.00 for the first 100 downloads.
Best regards
Mike Testro