Give us your thoughts on this, particularly if you have direct experience.
I’m at odds with a colleague about how much in labor is saved when the same project is replicated a second time.
For a project the size and scope of say (let’s name one most are familiar with here) Mike Smith’s “Adverse Conditions” job, one in which your or your employees direct labor will be used to build, from foundation to finish, a new 3 BR, 2-1/2 bath house.
That direct labor will include most everything except for subcontracted items that include excavation and sitework, plumbing and heating, electrical work, sheetrock work, some painting, and some incidental specialties.
Here’s a round number. Let’s say the first one had a total cost, payroll, taxes, and insurance, of $75K.
How much will you save the second time, repeating the same job?
Replies
Y = (A) x (X)-n
Y equals A times X to the -n power
Where:
Y = the person-hours required to produce the Xth unit of work
A = the measured value of the hours required to produce the first unit or work
X = the number of work units produced
n = the derived exponent that describes work output variation
n = 0.169917
For two units it would typically take about 88.89% of the time of the first one.
No. of units
1 100.00
2 88.89
3 82.97
4 79.01
5 76.07
6 73.75
7 71.85
8 70.23
9 68.84
10 67.62
Y = (A) x (X)-n
Y equals A times X to the -n power
Are you sh!ttin us ? This is breaktime not a remedial math class... =)
sorry I couldnt let it go by. lol
I do not know how to get a superscript or subscript to work on this message board. You would be surprised at how many in the building trades do not know how to raise a number to a negative power.
dude,I was just dicussing that very thing last week with my drywall and paint subs. No wonder the trades are going downhill
Barry E-Remodeler
Mathematically that's beautiful, but that probably assumes that certain conditions can be replicated identically, such as the labor pool (same men), weather (time of year), materials availibility, and so on.
I would have GUESSED 80%, but like the numbers better.
This is another:Working overtime for an extended period of time adversely impacts productivity. Eff(%) = 100% -5 [(days -5) + (hours -8)]% Where:
Eff = Worker efficiency based on 100% for a regular 40-hour week
days = Number of days worked per week
hours = Number of hours worked per day
Got any more?
Reference?SamT
Guys that don't do things correctly the first time.....then argue that they did nothing wrong.....if made to agree to fix the problem, rarely put the time and effort into truely doing it properly. they'll just look for the quickest fix to appease you and get their money. JDRHI <!----><!----> 84310.51
They are usually found in construction management and engineering books.
Unit 9 session 8 on Powerpoint slides at http://agc.org/page.ww?section=Supervisory+Training&name=Certificates%2C+PowerPoints%2C+Other+Downloadable+Documents
SamT
Guys that don't do things correctly the first time.....then argue that they did nothing wrong.....if made to agree to fix the problem, rarely put the time and effort into truely doing it properly. they'll just look for the quickest fix to appease you and get their money. JDRHI <!----><!----> 84310.51
It'd take me longer, I hate repetition!
Doug
A-men to that Doug. That's why I LOVE remodeling!!!
I think that all depends on the level of expertise your work force begins with. if you had to train some of your help on the first job then naturally you could subtract that training/ learning curve time. if your help hits the ground running every day then the savings may be miniscule
300 : 220 is the rough frame ratio I've achieved on one house that I know of that I was involved in.
blue
"...if you just do what you think is best testing those limits... it's pretty easy to find exactly where the line is...."
From the best of TauntonU.
No historical hard figures but I would estimate 10% on the first time repeat.
gb9 gave a table, no math in a table, his table is a normal 'Learning curve"
Google "learning curve".
There are some tasks that have a learning curve that looks like this.
1. 100%
2. 50%
3. 49%
4. 55%
5 and on 55 to 60 %
There are other curves like that also.
Before you get married the effort is 100%. The first year it is only 50%., the 40th year it is 200%.