“these submittal activities are screwing everything up,” i told my boss. “the project’s critical path is completely messed up.”
there were 576 submittals to log. each one took 2 lines in my p6 schedule. that was an extra 1,152 activities to manage and update, a lot of extra work from my perspective. i didn’t like this notion.
“the owner’s guy want to see those details or he won’t approve the project schedule,” my boss told me. like me, he disagreed with the whole approach of putting every submittal on the project schedule. it was too much detail.
the owner insisted. or his scheduling consultant did.
“we want as much detail as possible on the project schedule,” the consultant told us.
we tried to push back and explain that the submittals items added nothing to overall schedule work plan. he insisted. bigger battles, eh. so what could we do?
i knew it wasn’t going to pretty. i worked some serious excel magic to import all 1,152 submittal activities into primavera p6, all the while hating how this extra detail was going to mess up my critical path that was so clear. arg!
forty years ago, you would never find a project schedule that had too much detail and was overrun with tasks and logic. in those days, scheduling was either done with pen and pencil or on early computers that couldn’t handle the large amount of calculations.
today, it’s no wonder we see enormous detailed project schedules, in the range of 20,000+ activities. the technology has enabled us to add infinite detail and computers can handle it easily – sometimes much more detail than is necessary or reasonable.
i’ve seen many projects that become so large that the scheduler cannot maintain them. the result is that they
- fall behind in making regular updates
- are unable to properly integrate change requests
- are hesitant to make adjustments
- become enslaved to managing too much detail – things then go off the rails
if your schedule has too much detail, you’re likely to end up completely overwhelmed in trying to maintain it, at peril to the project. you become a data-entry clerk, not a project controller. keeping up with updates and changes takes all of your time. then there is no time for assessing, forecasting and analyzing project performance.
as my special guest reveals in the video below, the key to this problem is understanding your confidence in the schedule and the level of detail. what is your confidence in the project schedule and the level of detail? – a question you need to be constantly asking yourself as you build and work with your project schedule.
i’ve invited dr. saleh mubarak, author of construction project scheduling and control, to weigh-in on this question in this month’s ask planacademy video.
project schedules: how much detail is too much?
video transcript
michael: hi everyone. thanks for coming and joining us on ask 世界杯2022亚洲比赛时间 . i’ve got a special guest who’s going to join us and answer your question today on ask 世界杯2022亚洲比赛时间 . so today’s question is this, how big should my primavera p6 schedule be? how big as in how many activities?
so, this is a question i get a lot and it’s also a problem that i see a lot of. we often see massive schedules like 30,000 activities. and there is a major problem with those schedules. when they are so big, they are incredibly difficult to manage and update.
so, i am going to invite dr. saleh mubarak to come in just a second in help you figure out how big and how much detail you should put on your schedule. saleh, come on in.
dr saleh mubarak: alright. thank you, mike. that was a good question and i get that question as well. in fact, i remember years ago i was teaching this seminar in a different country and the chief scheduler come to me and asked me, “i want you to look at my schedule and tell me if it is a good schedule.”
the problem was that schedule was for hydroelectric dam that involves a lot of elements that i wasn’t technically capable of understanding. and i wanted to give him a general answer that satisfies him. now if you asked this question probably 40 years ago, my answer would have been different. because at that time we didn’t have computers and people did everything by a pencil and paper.
so there was a high pressure on us not to expand those schedules beyond certain… maybe you know, 100 – 150 because manually it would be impossible. now we have computers and people went probably to the other extreme to dividing the project into as you said 30,000 – 50,000 activities. some people mentioned to me a project with a 100,000 activities. the problem is the management of this project, of this size with these details.
i want to give you an example here. if i have a building that is 24 floors – and you can see here, this is just a sketch, we have 24 columns. and those columns go all the way from the foundation to the roof. so i want to look at only, only the concrete items, alright?
so how many activities i should have in this. and 24 floors is kind of average project these days, not the largest. we have buildings that are even 100 floors or so. and we have even other tops of like a stadium and other structures that are very complicated.
in this, let’s start with… i am going to be using the csi master format. so at level 2, we can say that we have only 1 activity, 1 concrete activity for the entire building which is frp. frp stands for formwork rebar & placement of concrete, frp concrete work for building. and that is one activity for the entire building. of course, that is not practical so we say, “okay. let’s go to the next level, level 3.” and we are going to divide by floor, we have 20 floors. so, that 1 activity is going to be 20 activities and each one will be called “frp concrete work, 3rd floor”, 4th floor, 5th floor and so on. and now we have 20 activities.
but we say that is not enough because we are mixing apples and oranges. and we have 6 different concrete elements not including, of course, foundation. but on every floor we have 6 types of at least 6. it could be suspended slabs or different types. let’s say suspended slabs, beams, columns, sheer walls, stairs, elevator shafts. and then those 20 activities would be multiplied by 6 to indicate the type of concrete elements.
so now we have a 120 activities and each one will say “frp concrete columns, 3rd floor, sheer walls”, 5th floor and so on. but you may say that that is not enough. let’s break it down by the type of work. don’t say “frp formwork” is an activity, rebar is an activity, placement is an activity which is true. so we have to multiply that 120 by 3 and we get 360 activities. to me, that is a good point to stop.
but what if somebody said, “no, no, no. i want each column and each beam to have its own activity.” well, in this case, we have 24 columns multiplied by 360 so we have 8640 activities and that is only for columns, right? not counting the beams and so on.
this way the project would probably end up with 50,000 activities or so. and i wouldn’t go that far. so how far would i go?
well, i have a confidence relationship with the division of the project. what is my objective of dividing those activities – to have a grip on them. and that grip means a confidence in assessing that activity, in knowing the status.
if i ask you if you put the foundation of huge building as 1 activity and i came to you and i said, “what is the status, joe with that activity?” well, it’s going to be very subjective question because you have thousands of operations going on with the foundation. some of them are done, some of them are behind, some of them are ahead, some of them are not to be done until… not to start until 2 weeks later and so on.
it’s hard to give an accurate answer. so let’s divide that foundation into little activities and then if i ask you, “joe, what is the situation of the spread footings? well, you can tell me more objectively and more scientifically, “oh they are about 60%.” so i would divide the project until i get that confidence. i look at the number of units or days in it and i said, “i have at least 90% confidence that this is true.”
that leads me to the last point. would i have that… all activities in the project at the same level of details? not necessarily. maybe you have a bigger activity. let’s say we have excavation and its very simple. we are excavating 8000 cubic meters of sand. i don’t have to divide it while a concrete operation next to it – yes, i have to divide it to a further level of details because i can’t get a grip on it.
the key here is confidence. once you feel you are confident with an activity, stop. don’t break it down any more. and let’s say the confidence is not going to be 100% anyway. let’s put a threshold for us, maybe 80% or 90%. and once you reach that, stop.
to me, i can’t tell you there is an optimum number of activities for your project. and no one can give you a magic formula that will give you an exact optimum number of activities in your project.
it is your feeling as a professional. don’t go too much into tiny, tiny activities that will be a nightmare for administering this project. and don’t go in only few that would be also difficult to manage large activities.
and in fact, the optimum number between them lies in your judgment, in how confident are you with those durations and do you have good control over those activities.
final thoughts
so what about my schedule?
the owner eventually let us manage construction submittals by our own process – excel spreadsheet. the tasks stayed on the schedule, but the logic was simplified so as not to complicate the critical path.
overly detailed project schedules do not help you better manage the work. too much detail actually hinders your ability to work with the project schedule. as dr. mubarak says, let your confidence in managing an activity drive how much detail is needed.
