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(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?

(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.

Total float

12 replies [Last post]
Fri, 2007-08-31 07:19
Dante Manito
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Can anybody here help me fix my problem? My problem maybe is quiet simple for more experience planners. Just recently i develop a level 3 schedule for a petrochemical project a newly awarded project to our company.The project start will commence on July 15 2007 and mechanical completion on March 8 2009 as per milestone submmited by the client.But when i finished develop the schedule my project manager give me instruction to change the start date to September 15 2007.Here comes my problem - When i change the start date some activity bar color turns to red and create a negative total float as high as -51.How can i fix this problem?
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Fri, 2007-10-26 02:15
#1
Orlando Dizon
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I AGREE WIHT MR. Naas "COMMUNICATION IS ESSENTIAL". IF THERE’S CHANGE THOSE WHO ARE DIRECTLY INVOLVE (STAKEHOLDERS) MUST SIT DOWN AND WORK FOR BETTER UNDERSTANDING OF THE SITUATION SO FROM THERE APT SOLUTION WILL COME.

REGARDS
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Mon, 2007-10-22 07:05
#2
Waleed Mahfouz
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IN ADDITION TO ALL OF THIS YOU CAN ONLY CHECK THE CRITICAL ACTIVITIES, AND MAKE A GLOBAL CHANGE TO INCREASE THEIR RESOURCES BY 15 %. BEFORE INCREASING LL RESOURCES FOR ALL ACTIVITIES.
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Mon, 2007-10-22 04:06
#3
Richard Spedding
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Dante

The answer is as ever, communicate.

Ask the PM what gives - does the client milestone change, or is it the resources that must be increased. Once he has answered that one, assuming that the resources must increase, then as Clive says, make sure that you make sufficient allowance for the fact that doing things more quickly leads to inefficiency, so yes, allow something like 15% more resources to execute the critical activities 10% faster, then review the critical path, because it will have moved and other activities will need to be executed faster too. By the time you’ve done this three times you should be getting close to the correct answer.

Then when you give the answer to the PM, be prepared to pick him up off the floor because he will have agreed to the delay for no extra cost!!!!!
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Mon, 2007-10-22 00:59
#4
Muhammad Jawad Sh...
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Its very simple to guess the problem.
Once you fixed the finish milestone date and you change the start date by a delay of 2 months, the float will be negative 51 working days or 60 calendar days.
Just reduce the durations of your critical (red color) activities by increasing resources where possible or change the logic of program to fix within time.
Contact the PM, he must help you.
Take care
Muhammad Jawad
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Wed, 2007-09-12 20:58
#5
Clive Randall
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Thats about it
The more you accelerate the more climbing on top of each other occurs and the more reworking is neccessary.
Thats why I guess it would be closer to 15%
A bit of science and a slice of experience.
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Wed, 2007-09-12 14:36
#6
Dieter Wambach
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Hi Nar
just remember you time at school. Reduction of 10% from 100 is calculated on basis 100, whereas increase of work up to 100 is on basis of 90, which makes 11,11. More persons need more leaders, admin, communication... - makes 12-15%
regards
Dieter
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Wed, 2007-09-12 10:08
#7
Nar Thap
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Just wondering how clive figured out 12-15% resource increase by reducing 10% of duration? very precise. any relationships to calculate accurately resource increament vs schedule reduction?
cheers
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Wed, 2007-09-05 04:46
#8
Clive Randall
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I just did a bit of math (for Americans) maths for the rest of us.
Your project started as 600 days, your pm chopped 60 days off thats 10% less time and your wondering why things have turned red!!!!

Assuming your programme was correct you will need approximately 12 to 15% more resources to complete 10% quicker.

Thats always assuming you can get the resources and there is space for them on site to work.

Before you go changing your programme you should establish why the start date has moved and whether the end date is also movable. If not I would give the PM an idea of what this will mean to the project.

If he insists on the change increase your resources globally by 15% and then look at where you can logically save time.

Taking 10% out of the project is a big deal, its not just about getting a programme that meets the end date, its about real money having to be spent.
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Tue, 2007-09-04 09:07
#9
ashraf alawady
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in addition to the above , you can review the resources and the daily productivity.

by increasing the recources the daily productivity will be increased and the duration will be decreased.

Thanks
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Mon, 2007-09-03 04:06
#10
Daniel Limson
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You need to crunch the programme by reviewing the following:
- Duration
- Logic
- Relationship

Cheers
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Sat, 2007-09-01 06:29
#11
Arnold Puy
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All you have to do is to change the PROJECT MUST FINISH BY.

Regards..
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Fri, 2007-08-31 09:24
#12
john Barnett
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It sounds rather like you have created a schedule running from Jul 15 07 through to Mar 8 09. When you change the start to be Sep 15 07, you are shortening the number of days available to do the job hence negative TF. You now need to work out how to do the job in the fewer days
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