Quantity Survey!
I use Excel and Plan graph, their is other great software/ hardware out there that speeds it up!
I do not want to spend time on explaining inputting data in excel reading blue print and documentation. That is straight forward don’t know! Take a course!
But in construction it is most important, to plan out at same time is the flow process of material and men. Look at the space requirements, access to and from the construction site. Have method prepared for completing the job. Not detailing this part will bring about unforeseen expenses and slow down.
The faster and more cost effective one wants to be, the more detailed the job planning should be!
For example, one project I was part of! My job function; manage for subcontractor all mill work installs in high-rise. Our install has to conform to Canadian Mill work specifications. Painter comes after us, his job is to paint out the mill work and units. On his contract all he does is paint, on Canadian mill work specifications standard all mill work, the installer has to fill the joints, but no nail holes. The general contractor was stuck in this instance, for no specifications laid out for filling the nail holes in the mill work. He had to renegotiate with painting subcontractor during the project install.
Another instance is in high-rise construction the speed that has been achieved in Japan versus North American standards, is made possible by nothing more but knowing how long each small job segment takes. In planning and team coordination to the smallest detail.
In North America standard one floor per week in Japan they have been achieving two floors per week.
Here is where I get into some detail of how to achieve great detail in project planning!
I call it the work break down structure. In industrial Engineering it is referred to as a element. Tasks can be broken down to the smallest detail and measured using different techniques.
In other words, one can plan and measure in greater and greater detail, as to how the job is most effectively completely!
Take this example!
Let’s start with job of fastening drywall to wall on a project!
Tools are assembled; worker in place material is near! Work flow is starting!
Pick up sheet #1 of drywall move to location. (time required), (space required)
Fasten screws in drywall. (Time required), (tools required), (space)
Measure for sheet #2. (Time required), (tools required)
Trim sheet#2. (Time required), (Tools required), (space required)
Pick up sheet #2. (Time required), (Space required)
Fasten sheet #2 with screws. (Time required), (Tools required)
Work cycle repeats itself.
What are we looking at here! Are we looking at all the action in placing drywall?
Notice! One needs time values for each element. Tools and space need for work flow design.
Let’s go more detail for putting up drywall. In other words, make
the WBS (work break down structure) more detailed in order to be able to quantify it.
Let’s look at the step of fastening screws to drywall.
WBS for fastening drywall
Left hand reaches into pouch grabs small hand full screws. Time value
Left hand moves toward screw gun and sorts screws so one is between thumb and fore finger. Time value
Left hand and right hand meet, left hand places screw on gun tip. Time value
Operator judges looks for placement of screw while action 3 taking place. Time value
Right hand moves the gun with screw to location and lines up Time value
Presses trigger with to fasten screw. Time value
Left hand is sorting screws to get next screw lined up between thumb and for finger, while action 6 is taking place. Time value
Cycle repeats itself.
Notice the action of sorting screws with fingers so they line up in placement. That requires training high proficiency. Try it!
Next the action of placing screw on screw gun tip without looking at it and scanning for next placement of screw. Another degree of proficiency!
What one has here is a breakdown of work that can be measured and timed using various techniques.
Two things become apparent “the action of looking at the screw “adds another element to WBS.
When we apply time values it adds time.
The same with the element of sorting screws in fingers to prep for placement on screw tip.
There is a learning curve; the same with assembling bigger structure the individuals have to be a team to assemble fast there is a learning curve.
Here one can see already the power of breaking down the jobs into individual elements. One does not necessarily need to break the elements this far down like the one for fastening drywall. But when assemblies are complex involve different trades and speed is essential. Yes, it is worth it to plan too such extend.
Once one has time values attached to the individual elements.
One develops the process flow and Gantt chart out of this.
The process flow should include work station design and material flow. Even on construction site there are work stations, just not clearly defined and mobile.
Notice I did not use templates for WBS, the goal when doing a work break down structure is to minimize the work cycle without working harder just smarter.
I found it helps to visualize the WBS in many different ways, cost cutting ideas come!
Especially in complex situations.
THINK OUTSIDE THE BOX.
Example: When managing store installations, noticed the cabinets where always dropped off at a storage place then picked up and placed in location. Solution store is laid out, cabinet locations marked off , delay delivery until that point, then place cabinets in right location immediately. One element in WBS eliminated and was using delivery personal to place cabinets less workers needed on job site.
One important aspect not touched on it is essential when one does time study for costumer or one “wishes”, to develop equations for estimating.
Is the mathematical analysis of the data?
Every time one collects data inherently there is error.
To decrease error one must take many readings. The number of readings is calculated on the average error of the readings.
When managing jobs for clients never encountered a situation where a time study was requested. But I do take measurements to see how fast the job is progressing. It is like the gas pedal of the job especially when they are large. I use the software “Work-study 4 “. It is a significant improvement over the stop watch and clip board time analysis. Very fast unobtrusive, just do not get to take the number of readings to get the error margin to 95 percentile accuracy. More time would be needed.
But is way better than guessing, or sub-contractor telling me stories about his production rate and it is not there!