Activity Padding

Hi Dr Paul.

A weather contingency is best placed on the callendar allocated to outdoor trades. Anticipated weather can then be substituted for real weather in the weekly update.

Simple realy.

Best regards

Mike testro

Mike,

The calendar method shall be applied to determine extension of time but not for managing the schedule.  What if you plan for some rain and assume it will be tomorrow but it does not rains, the schedule will misled people into not working tomorrow.

Critical Chain promotes the use of separate activities as buffers to avoid padding, which is an improvement, but is flawed with regard to feeding buffers because as soon as the critical chain changes they might no longer be feeding into the critical chain and if not enough new feeding chains will happen.

https://wafimohtaseb.com/2012/05/27/project-scheduling-best-practices/

A better approach is favored by Spider Team, it does not depend on padding, it does not use activities to represent buffer, no special software is needed to apply the concept.

http://www.spiderproject.com/images/img/pdf/Success%20Driven%20Project%20Management%20Paper.pdf

Best Regards,

Rafael

I do not like strategies that promote lies and deception, schedules shall be transparent and not a bunch of lies.

Hi Rafael

You only stop work when the weather is bad - not when you have a wet day forecast on the programme.

Best regards

Mike Testro

Exactly, but still some people insist you manage with a plan that includes the assumption for some rain at specific dates or range of dates.   This is basic project risk management.

Hi Rafael

Most peopeprefer to do it properly.

Best regards

Mike Testro

It is wrong to manage a schedule under the assumption it will rain tomorrow and therefore there will be no scheduled work for tomorrow. 

• To manage field schedule a 100% non padded schedule is necessary; this means no rain padding. 
• To manage the contract a schedule that considers the rain allowance as well as, other contingencies, buffers and terminal float is necessary. 

Both shall be transparent, otherwise those in direct management of the means and methods will have no other option than to recur to a Ghost Schedule.

http://www.stevencevans.com/float/

http://www.fplotnick.com/constructioncpm/2016Presentations/MON37-PPR.pdf