Here is small tabular example for the same yesterday I had tried to explain in descriptive form, we plan to build a sleeper foundation A-1 and we try to roll up the progress up to foundation level from detail activities using duration and cost as weight factor
Weightage Progress
Description Dur Cost OD Cost Act FDN as OD FDN as Cost
sorry but i did not make myself clear, my question what is wrong with making the duration of activities as the weight factor for project summerization.
mimoune
ps ; Tahir hope the local subcontractors are doing well.
Member for
19 years
Member for19 years
Submitted by Tahir Naseem P… on Sat, 2007-02-10 16:38
As explained by brennan that the duration base progress calculation will always in linear basis but it have some other impact such as if you are plan & monitor a civil foundation the duration foumula totally failed and base less such a simple foundation of 2 mtr cube may be require to construct in 7 days including excavation/dressing / compaction/formwork/rebar/lean and pouring but the curing period always 7 to 21 days but with a very less cost and manhours. In this case the progress representation on duration base totaly reflect the opposit to physical progress at site.
Cheers
Member for
22 years 8 months
Member for22 years8 months
Submitted by Brennan Westworth on Thu, 2007-02-08 21:37
In my opinion progress should always be physical % complete.
Although there are arguments for and against it, I never use the autocost rule that links remaining duration and % complete.
At a summary level this is even more important. To really simplify it, consider a project that assumes a standard S curve for its progress. if you are using ratio of durations, the progress you plot will be linear.
Using the earned value method (resource units or cost) will allow you to not only summarise progress to the project level, but to any other level within your project you may need to analyise.
Member for
19 years
Member for19 years1 month
Submitted by mimoune djouallah on Thu, 2007-02-08 15:01
automatic calculation of % complete at an activity level depends on your autocost rules (RD linked or not)
But i think the question was partially addressed by your second answer Prabin.
Summary progress for a project can be calculated by ratio of durations (not advisable) or by earned value using resource quantities or cost.
you need to be careful using resource units that you are summarising one unit of measurement only (ie manhours) and not mixing them up (manhours, m3 of concrete, plant hours, etc).
For project level summary i would recomend cost be used.
Member for
20 years 1 month
Member for20 years1 month
Submitted by Prabin Kumar on Thu, 2007-02-08 06:09
Member for
21 years 7 monthsRE: pc% for project- what are rules p3 depend on?
Pals
Interesting discussion...
Every system has its faults... We should find a system works for us.
Unit duration is good when activities are equiworth and similar nature ( like Civil Works, Installations) Curing should not be listed as an activity.
In case if we use cost in an EPC Elect.project, Civil may be 30% delay and if transformer arrives 1 month early we will be ahead of schedule...
Am I correct.
To measure physical progress Manhour may be the right unit.
Regrads
Yembee
Member for
22 years 8 monthsRE: pc% for project- what are rules p3 depend on?
do i detect a note of sarcasm there mimoune? :)
Tahir’s example illustrated the difference between physical progress and ratio of durations perfectly.
consider a simple concrete structure... say a pad footing.
Two activities:
Form/Reo/Pour Footing (Duration 7 days)
Cure Footing (Duration 28 days)
using the ratio of durations method for summarisation, once you pour the footing you will be reporting only 20% complete!!! 7d / (7+28d)
Member for
19 yearsRE: pc% for project- what are rules p3 depend on?
you rock guy; thanks really
mimoune
Member for
19 yearsRE: pc% for project- what are rules p3 depend on?
Dear Mimoun
Here is small tabular example for the same yesterday I had tried to explain in descriptive form, we plan to build a sleeper foundation A-1 and we try to roll up the progress up to foundation level from detail activities using duration and cost as weight factor
Weightage Progress
Description Dur Cost OD Cost Act FDN as OD FDN as Cost
Excavation/compaction 2 1000 12.9% 11.1% 100% 12.9% 11.1%
Lean concrete 1 1500 6.5% 16.7% 100% 6.5% 16.7%
re-bar Work 2 3000 12.9% 33.3% 100% 12.9% 33.3%
Formwork 1 500 6.5% 5.6% 100% 6.5% 5.6%
Inspection , go head pouring 0.5 200 3.2% 2.2% 100% 3.2% 2.2%
Concrete Pouring 1 2500 6.5% 27.8% 100% 6.5% 27.8%
Curing 7 100 45.2% 1.1%
Inspection and H.O to Mechanical 1 200 6.5% 2.2%
100% 100% 48.4% 96.7%
I hope this example is self explanatory, why the cost or resources widwly use to roll up the progress to summary level.
Member for
19 yearsRE: pc% for project- what are rules p3 depend on?
thanks Brennan, Tahir for your explanation.
sorry but i did not make myself clear, my question what is wrong with making the duration of activities as the weight factor for project summerization.
mimoune
ps ; Tahir hope the local subcontractors are doing well.
Member for
19 yearsRE: pc% for project- what are rules p3 depend on?
Dear Memoun
As explained by brennan that the duration base progress calculation will always in linear basis but it have some other impact such as if you are plan & monitor a civil foundation the duration foumula totally failed and base less such a simple foundation of 2 mtr cube may be require to construct in 7 days including excavation/dressing / compaction/formwork/rebar/lean and pouring but the curing period always 7 to 21 days but with a very less cost and manhours. In this case the progress representation on duration base totaly reflect the opposit to physical progress at site.
Cheers
Member for
22 years 8 monthsRE: pc% for project- what are rules p3 depend on?
Mimoune,
In my opinion progress should always be physical % complete.
Although there are arguments for and against it, I never use the autocost rule that links remaining duration and % complete.
At a summary level this is even more important. To really simplify it, consider a project that assumes a standard S curve for its progress. if you are using ratio of durations, the progress you plot will be linear.
Using the earned value method (resource units or cost) will allow you to not only summarise progress to the project level, but to any other level within your project you may need to analyise.
Member for
19 yearsRE: pc% for project- what are rules p3 depend on?
Hello
Brenna wrote
@Summary progress for a project can be calculated by ratio of durations (not advisable)@
can you explain more ?
mimoune
Member for
20 years 4 monthsRE: pc% for project- what are rules p3 depend on?
Forat,
In the projects i got involve with, it is the planner who calculate the percent complete of each activities.
Charlie
Member for
22 years 8 monthsRE: pc% for project- what are rules p3 depend on?
automatic calculation of % complete at an activity level depends on your autocost rules (RD linked or not)
But i think the question was partially addressed by your second answer Prabin.
Summary progress for a project can be calculated by ratio of durations (not advisable) or by earned value using resource quantities or cost.
you need to be careful using resource units that you are summarising one unit of measurement only (ie manhours) and not mixing them up (manhours, m3 of concrete, plant hours, etc).
For project level summary i would recomend cost be used.
Member for
20 years 1 monthRE: pc% for project- what are rules p3 depend on?
P3 calculates % complete by calculating the percentage of actual duration spent wrt Total duration. i.e (OD-RD)/OD
For summerized activity, this can be set in three ways, i.e. in respect to Duration, Resources unit and cost.
thanks,
Prabin