Sequence of material submittal in the Program

Hi Kannan

No it is not good practice.

Replace the lead lag with a named task so that everyone knows why it is there.

The only place for a FS lead lag is for drying out or curing periods and they must be set at a 24/7 calendar.

Best regards

Mike Testro

Hi Mike,

Thanks for the reply. I also have the opinion that FS with a lag is not a proper way.

But for the materials submittals many of the materials are required in a later stage of the Construction. So the Contractor will arrange the materials in a later stage only since there will not be enough storage space at site.

In that case- it may not be possible to fill the lag with an activity. In your experience what could be the done to fix it.

Regards

Kannan

In this case it makes sense to consider space constraints in project scheduling. This can be done in Spider Project.

Another option - Just In Time scheduling when supply activities are made ALAP (not in Microsoft Project!).

Hi Kannan

It is not difficult to create a rolling delivery schedule of materials linked to stages of construction.

Imagine a high rise tower with blockwork partitions.

With a detailed bottom up programme you will know when each level of blocks needs to be in place and the delivery scheduled accordingly by an ALAP linked task.

By using a resource called "blocks" with a volume limted to the storage space you can run a histogramme to ensure that the material is never over stocked.

Best regards

Mike Testro

another option that you might want to consider is using the as late as possible constraint this will schedule the activity as late as possible without delaying its successor activity in your case it would probably be procurement/delivery of the item that your are submitting. As mentioned by Kannan this will prevent the material form showing up on the project too early especially when there is limited space. 

1. ALAP constraint is not allowed in the program as per Client instruction.

2. In my understanding there is a draw back by using this constraint. If there is a delay in the start date of a construction activity, the corresponding material delivery activity will be shifted. So it may not be possible to show the planned material delivery in the updated programme.

Regards

Kannan

Calculated ALAP delivery dates are used for creating delivery schedule. If it is created and accepted the dates are defined by this schedule and there is no need to use lags in FS dependencies.

Besides some materials may be used on multiple activities. In this case FS dependencies do not make sense because it is not clear what activity will use delivered materials.

There is a common misconception within schedulers that an activity can be 100% equivalent to a time lag.  Lag  represents elapsed time that will happen no matter what as time elapses while an activity can be delayed no matter how much time elapses.  An activity needs to be updated while lag or time passage is always calculated automatically. Similar but not equal.

The same goes with volume of work lag, to be used when passage of time is not enough but a certain volume of work. 

It is better practice to use lag when you need to model passage of time or realization of some volume of work no matter if SS/SF/FS/FF.  People whose software is poor at displaying a links table, or software not good enough to allow you to define independent lag calendar will ask you to use an activity.  Concrete curing time is dependent on consecutive days while predecessor, successor and main calendar might be different to consecutive days, software such as P6 have issue with this. 

Materials are consumable resources.  Consumable resources cannot be correctly modeled using regular renewable resources, you need different functionality.  It is incredible a few software of the 80's had this functionality such as MicroPlanner but eventually most of today software lacks it.  Spatial resources are considered a separate type of resource by many but can be modeled using consumable resources functionality. 

Microsoft Project and Oracle Primavera P6 lacks functionality for consumable resources, many users of these software are unaware of what it is.   If your resource needs are a bit complex better use the more modern software such as Spider Project that can correctly model all these scenarios. 

Hi Kannan

Your option 2 is a benefit not a drawback as the delivery requirement shifts in relation to when it is actually required.

This facilitates both storage and cash flow.

Best regards

Mike Testro

Mike,

Why I said it is a drawback is because in any of the future EOT claims everyone will concentrate on the agreed date of delivery as per the baseline.

Regards

Kannan

Kannan

Ask the client why the ALAP constraint is not allowed in the program. There should be a good explanation for this not just because is it in the specifications.

There is no draw back by using this constraint. You said that "If there is a delay in the start date of a construction activity, the corresponding material delivery activity will be shifted."  

That is the whole point of using this type of constraint. If the construction installation is delayed then you WANT to delay the delivery of the material. If the material is not need to be on site why would you want it delivered taking up valuable space on your project with the possibility of theft, or being used somewhere else or damage to the material that does not make sense.

This constraint does exactly what it is supposed to do that is the whole reason why it was created in the first place. Tell the client that using this constraint is better than using lags. The draw back with lags is that if the installation is delayed then you MUST change the lag. The beauty of using the the ALSP you do not have to do this.

You can see that Mike says the same thing as I did about it being a benefit NOT a draw back 

Hi Zoltan,

I have a scenario in mind related to the claims.

For eg: there is a delay from the client to alow the site or particular building handover(for MEP works) to to the Contractor. This will delay all the construction works and the delivery items will be shifted accordingly(ALAP Constraint).

Later when the contractor apply for the EOT/Prongation cost, the client may defend that the program shows the material delivery was also late during the delay event.

If it goes to the arbitration/court, we should explain court what is ALAP constraint and to provide the records of delivery status  during the delay event and its link to the construction activities.

Is the above scenario possible in a project?

Regards

Kannan

yes the scenario is possible but you are chasing the wrong chicken. You should be submitting an TIA for the construction activity that was delayed. I understand what you are tring to say is that you want ot sya that you were all dressed up and no place to go. Meaning all of the material was available but the construction activity was delayed. From the owners standpoint are are also looking at a concurrent delay situation delay here. I would argue that the delivery of the materail was scheduled to support the installation. If the installation was delayed buy the owner then there is no sense in bringing the material to the site. Would the owner be willing to pay for off-site storage of the material ? Would the owner be willing to pay you for the stored material even if it is not on site? Probally not so now what happend to your cash flow when you have to pay for storage of the materail that you may not need for several months. So by using the ALAP constraint you are saving the owner and you money. I am sure that he would be interested in this approcah. 

Hi Zoltan

Your approach is correct - it is called "pacing" and arbitrators understand it very well.

Best regards

Mike Testro

Hi Zoltan,

I totally agree with your concept. Thanks for the explanation.

Regards

Kannan

yes Mike it is but I was just trying to explain the whys and hows. If I just said pacing the person that asked the question would not have understood that and we would have gone around and around on pacing. 

Hi, Zoltan and Mike

Hi Jimmie,

In my understanding, you can still claim the EOT for 6 months delay from the Employer side, regardless of your delay. But in case of prolongation cost, you can claim for 0.5 month only, because of your concurrent delay.

Regards

Kannan

Hi Kannan

Agree with your point.

In this case, suppose we can control our design works, i.e. the material delivery on site is under our arrangement, for not losing the entitlement of prolongation cost for this 6 months, we still need to get the material on site as per baseline program instead to shift the delivery as per site progress. If my understanding is correct.

Best Regards.

Jimmy

 no you would only be entitled to 1/2 month because it was a concurrent delay situation where in this case you were responsible for the design. Since his delay was longer than yours by only 1/2 a month then 6 months vs 5.5 months you are only entitled to the non-over lapping portion of the delay of 1/2 month.

Hi Jimmie,

As Zoltan informed before, we can shift the delivery of material as per the requirement on site (for eg if there is delay from the Client side)- no use in expediting the material and wasting the limited space at site. If there is no delay from Client, the Contractor's execution work should go as per the plan and the material should be delivered to site as per plan.

Regards

Kannan