Updated: Sep 11, 2021
A CPM (Critical Path Method) review in construction is when a project schedule is reviewed using the Critical Path Method.
This is where the tasks in a given project are reviewed to find the shortest possible time to completion.
The way this is done - and a hint at the reason for the name of this technique - is to find the longest chain of dependent tasks throughout a project.
This means tasks that must be finished before others are started.
A simple example is building a house.
Before we construct the walls, we need to build the foundation.
Likewise, we cannot put in windows before the walls are complete.
So we now have a list of dependant tasks that are critical to the project completion (not just added extras!)
From this then, we look to take all of the tasks in the project, differentiate the critical (necessary) from the non-critical, place them in order based on dependencies and calculate the total proposed project length based on the proposed times for each individual task.
Now, as lengthy a process as this sounds, we now have a variety of different technologies that might do this for us in a few clicks!
Okay, but why is it important?
CPM Reviewing has a host of benefits, here are a few to help us understand how important it is:
Establishing the fastest route to construction project completion
Do things in the most efficient manner.
We want to complete our projects on time.
We want to complete them within budget.
Therefore we need to do things in the most efficient manner.
CPM reviewing of a schedule shows us the fastest possible route to completion.
Going through the process laid out briefly above, we might very quickly sort out the necessary from the unnecessary and have a clear methodology for finishing our projects as quickly as possible (before moving on to others and scaling our business!)
CPM Reviewing really is a necessary process for any substantial project - overlook at your own (financial and time) risk!
Obviously from the above benefit (quickest possible completion) we hope to derive the two often sought benefits to scheduling techniques also - reduced costs and reduced delays!
Show up errors
A quick CPM Review might bring to light buried errors in a construction schedule.
For example, it may be that a dependant task has been scheduled before or during its predecessor.
Like, putting in the windows before the walls have been finished.
In doing this, we might detect issues in projects that we didn’t previously know were there - before they cause an issue on-site (or in pocket!)
Efficient use of resources.
In running a CPM Review we might find exactly where we should place our resources during a construction project.
For example, we run a CPM review and find that between scheduling finishing the walls and putting in the windows, we have scheduled for our contractor to begin decorating the exterior of the house - before doing the roof!
As the decorations are an added extra and the roofing Critical (i.e. necessary to project completion) we should, instead of using resources on non-critical tasks and delaying project completion, employ them on finishing the critical tasks.
This way, we might yes, deliver on time as mentioned above - but there are more benefits than that:
Since there may be a point in the contract where there is a bottleneck for project speed - an example might be having to wait on a particular, few resource-requiring, critical task to be completed before other critical tasks can proceed - this is a time we might use to do those added extras.
This way, not only will we have put the first things first - but also filled empty hands at quieter points in the schedule to keep our construction project in the budget.
How to do a Construction CPM Review
To do this topic justice requires another post, but as mentioned above this is an area where software does the majority of the heavy-lifting nowadays.
Schedules are created first in a common project planning/management software like Primavera P6, then loaded by an additional plugin software like Claim or Schedule Cracker.
These technologies are made to analyze schedules by a host of metrics and find the most efficient way of going about the project - sniffing out any risks or issues within them!
They then have functions for reporting these findings, with recommended actions and explanations.
What is a Construction CPM Review?
CPM Reviewing is an essential technique for Construction (or any!) project planning and good performance.
It’s not only something that should be used at the beginning of a project - to review or draw up a schedule - but at every schedule update.
Though we may be excited to complete projects and deliver - rushing in might cost millions of dollars compared to taking a few minutes to simply devise the best possible strategy.
Building without proper schedule reviewing may just be the noise before delay - take care of your business and your projects and take a few minutes to run your schedule through software to put you ahead of the competition.
To read more about this software and how you should use them to close projects and grow your business.
Thanks a lot for reading and take care,
The Project Cracker Team