PMBOK does not offer recommendations or guidelines for frequency of updates, other than to state that the length of the reporting period is an assumption/constraint that is considered when estimating activity durations. Few publications actually provide recommendations in this arena.
AACEi, in the Recommended Practice No. 23R-02 "Identification of Activities
", states, "An early decision that should be made by the team during the planning process
is determining the level of detail and general number of activities appropriate for managing the project
." and "Some considerations in determining appropriate levels of detail include:
• Duration of Project – Shorter duration projects typically require less level of detail than a longer
duration project. As a general guideline, activity durations should be approximately the same length as the
project’s planned frequency of progress status reporting.
• Project Complexity – Complex projects may have short durations, such as maintenance outages measured in hours,
but may still require a greater level of detail in activity identification.
• Execution Methodology – Projects with a high level of sub-contracting generally require less detail than
self-performed projects.
• Phase of Project – The level of detail in activity identification should match the type of work being
performed, and the information available, for that phase. For instance, during the conceptual phase,
start-up may be planned with summary level activities, whereas design engineering may be planned in greater detail.
• Cost of Project – Generally, the higher the cost of the project, the greater level of detail in activity
identification.
• Cost and Ability to Adequately Review the Schedule – The owner of a project should not require the submission
of a schedule that is more detailed and complex than the owner is able to properly review. As a required
submission, the schedule becomes a formal notice of the contractor’s plan and the owner is responsible for a reasonable understanding of the contents.
Cost of Maintaining Schedule – A higher level of detail in activity identification typically results in
increased cost of maintaining and statusing the schedule. This is an important tradeoff that the project
team needs to consider in their planning.
• Client Expectations – The client/owner may have specific schedule requirements that may determine the level
of detail required in activity identification.
• Project Risk – Typically high risk projects are planned in detail to assist in risk mitigation.
• Measurable – When identifying activities, the team should ensure that every activity can be easily measured
and uniquely controlled."
Saleh Mubarak, in his "Construction Project Scheduling and Control" notes that "Construction
schedules may be updated monthly, biweekly, weekly, or according to another time interval. Weekly and biweekly
are probably the most common frequencies."
Now, my opinion :
There are several factors
that drive the frequency of updates; number of activities (some of this is the physical ability to update),
need for monitoring (the more sensitive slippage is, the smaller frequency needed), work schedule
(multiple shifts will require smaller frequency), management needs (for weekly management using the main
CPM schedule, weekly updates are needed), responsibility for activity work (decomposing to a level to
assign single responsibility will increase the number of activities), size of smallest preferred duration
range, detail of the area designation plan (if there are specific areas that must be kept separate, it will
require more activities), reports needed (if you need to report per trade or room, then the level of detail
needs to reflect this), extent of changes and delays (you will need a short update period to be able to
effectively and objectively analyze delay and time extension requests if there are a lot of them - if you
get 4 requests or delays a month, than monthly updates is not frequent enough).
While most projects provide monthly updates for reporting due to owner requiements, I am a strong believer
that the schedule should be a management tool, reviewed every day by the project manager and updated weekly,
with some analysis performed weekly in the way of trending and predictions. That committment to weekly
updates will improve management and help control the project, so that is my recommendation.
The only other book
that I can think of that may have recommendations as to frequency of updates is the AGCs
"Construction Planning and Scheduling". Someone has borrowed mine, so I
cant look it up.
Hope this helps,