(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.
Hello everyone,
this is my first post here.
I have been looking for an answer to this a long time but still haven't found a satisfactory one, so here goes:
I have a Bill of quantities for a construction object that has around 100 items. Now some of these are too small to include into a separate activity for example *ANTIACID COATING - 5m2* which would take 2 manhours. There is no point making an activity out of it, yet I can't omit those activities.
Another example. Say we have a concrete foundation of 2m3. If we separate it to rebar-formwork-concrete then we will have 3 activities and each will have duration of 2 or 3 hours.
What is the practice with these cases?
Printer-friendly version
Send to friend
If I put cranes and batching plants in a hammock activity, then I cannot do leveling on that resources, right? Not that I would want to, but just to clarify.
Mike, I also think that the driving resource should be an excavator because we should always have excavator busy and trucks are less expensive so they can wait.
Mike,
if the number of haul units is large enough an excavator deterines productivity.
We put tower crane cost on the hammock because its time is paid independently of its work but in most cases it is limiting resource and we assign it to the jobs where it is used with certain workload (percent of work time). Some activities are delayed because they need tower crane that is busy on other activities.
Hi Milos
You have to seperate the driving resources from the passive. The duration of the task is determined by who or what is doing the work. For instance in a bulk excavation the haul units determine the output - not the excavator. In a pipeline it is the welding that drives production.
A skilled planner will know how to seperate the active and passive resources.
Machines such as tower cranes and batching plants are best placed on a hammock summary of the tasks that need the machine.
Most software has a system for dealing with materials - consumables - but they are not progress drivers.
Best regards
Mike Testro
Milos,
we don't use P6 but I think that the answers to your questions do not depend on the software used.
We usually separate jobs performed by different crews and requiring different materials. So we create separate activities for rebar-formwork-concrete even if activity durations are short. But jobs that are performed by the same crew may be united in one activity if its durations does not exceed the period for project performance analysis.
Rebar, anker bolts, concrete, etc. are materials that shall be assigned to corresponding activities. We usually use norms (material amount per work volume unit - m3, ton, piece, etc.) but P6 does not work with norms, so you shall assign total amounts.
Thanks.
Then if I want more detail I use rebar and formwork as weighted steps, right?
And what about materials? Do I add rebar, anchor bolts and concrete as material? Or is that overkill?
Also what about machines? Is it customary to put those as resources too? And what is the logical way of calculating machinery, there are no norms for cranes or transport trucks or skid steer loaders...
Hi Milos
Almost right.
Rebar bending is done in advance of the installation so should be left out.
Best regards
Mike Testro
Thanks for the reply, Mike.
So, I am trying to get this right, you said:
"1. Convert the BoQ to net rate - no OHP.
2. Set a percentage for the labour content of the rate - ask the estimator if you don't know.
3. When you have the labour value divide it by the labour cost to get the number of resource hours to allocate to the task."
I can do all this using company normatives, and get the labour hours for every item.
So then I group a couple of items e.g. rebar bending, formwork, rebar installing, concrete pouring, anchor bolts, steel plates... into one activity "Making of concrete foudation" which has Qty of 10m3, and allocate resource hours for all items associated, right?
Hi Milos
In your example the only BOQ item you need to consider is the installation of anchor bolts. That is a permanent resource topic the others are supply items.
WBS is no use in resource loading - you have to use the Unique Task Indentity code - UTID - so when you have a number of BOQ items for Ground Floor Rebar you set them in a spreadsheet and allocate them the programme UTID.
You can then total up all the BOQ UTID items and allocate the total to the schedule.
If the BoQ price is not broken down into Labour Plant Material then you need to tease out the labour resource content of the BoQ items. This is done by:
1. Convert the BoQ to net rate - no OHP.
2. Set a percentage for the labour content of the rate - ask the estimator if you don't know.
3. When you have the labour value divide it by the labour cost to get the number of resource hours to allocate to the task.
It is much easier to use a single resource for Labour Hours - don't try to break it up into multiple trades. You can do an S curve on different trade by doing a code filter for the work tasks.
Best regards
Mike Testro
Okay, I have another example which is very interesting to me:
What to do when we have couple of lines in BOQ that apply to a same position for example:
| SUPPLY OF ANCHOR BOLTS FE430-D EN 10025 ACCORDING TO SPECIFICATION 4379.0 | kg | 288,00 |
| EXTRAPRICE TO ANCHOR BOLTS SUPPLY FOR HOT GALVANIZING PROTECTION | kg | 288,00 |
| INSTALLATION OF ANCHOR BOLTS DIA. UP TO 20 mm ACCORDING TO SPECIFICATION OR TM 903.10 | No | 72,00 |
These are basicaly the same position. What do I do with this? I make an activity "installing 72 anchor bolts", and use price for all three?
Hello Mike, thanks for the reply. I still have problems but cannot formulate my question yet :) I'll get back to this when I run into some real-life example.
The hardest part for me in planning is making the WBS and deciding on the activities. I would like to learn as much as possible about it, if you know any good resources on that topic I would be very grateful.
Thanks in advance
Hi Milos - Welcome to Planning Planet
You do not build to the BOQ so you do not micro plan to it.
Set out your programme to the proper build sequence and then resource it from the BoQ.
So the 2 m3 concrete base would be part of the resource loading for the foundations resources.
Best regards
Mike Testro
Email: PPadmin@planningplanet.com
Replies