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Process Perils & Profit | Pro Builder

Scott Sedam writes another great article on lean implementation in the building industry…

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Thinking Begets Thinking

A great Deming-ism I just stumbled across in my old notes  from a Scott Sedam article How To Get Smart from the 7/11/2000 issue of Professional Builder:

Deming lamented that our companies and our country were becoming so obsessed with job skills that we were turning every educational endeavor into a trade school. He had nothing against trade schools, but he said it is an insult to not give people the opportunity to learn, grow and develop by thinking — not simply teaching instructions and procedures. And this goes for people at all levels. Knowing the fact or the thing is usually less important than knowing how it got that way.

My favorite Deming example that he used to illustrate goes as follows: Take two kids. Give them each an assignment. Tell one to go find out the name of the capital of Wisconsin. Tell the other to find out why the capital of Wisconsin is Madison. Deming would simply smile and say, “Oh, what a difference.”

The difference, of course, is that student No. 2 would have to research, explore, think, reason — work his brain. And here’s the key. The next day, at his job at the Costco warehouse, Student Two would be much more likely to think of a better way to do a job. Thinking begets thinking.

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Productivity: The debate over one-person (lead carpenter concept) vs. two (or more) person crews

I’ve been thinking about the issue of “productivity” and the debate over one-person (lead carpenter concept) vs. two (or more) person crews.

When I open up my estimating application or crack open a copy of R.S. Means’ Repair and Remodeling Cost Data I might see a line item that looks like this:

Description Crew Daily Output Qty Labor Hours
Interior,passage door, 4-5/8 solid jamb,Luan finish, solid core, 1-3/8″ x 6′-8″ x 2′-6″ wide
2 Carp



Lets say I have a job to install twenty of just the door they are describing there. I’m going to use that .800 Labor Hours figure times the number of doors (20) to come up with a figure of 16 Labor Hours to install the twenty doors. While I think that generally speaking hanging doors is a solo carpenter job I can see there that R.S. Means has based there figures on a two person crew. I going to interpret that to mean that while they may see the task as primarily solo too they feel there are times when having and extra set of hands can sometimes help so the .800 Labor Hours per door figure is based on that. So I go with that and let that be my guide.

I will then take that 16 Labor Hours to install the twenty doors and then multiply it by my Loaded Labor Rate of $85 per hour to come up with a Price of $1360 to install those doors. My Cost Estimate is done.

The text I’ve highlighted in bold red goes to so questions I have regarding productivity. When I first began to look at the topic of “How long does it (really) take to do something that’s been estimated to take 200 labor hours?” (JLC-Estimating & Markup Forum—Estimating Conundrum #2 How long… March of 2003) I was trying then to look at it in almost a generic form without looking at the issues of crew size so that I could examine some very basic scheduling issues.

The truth of the matter ( and there were plenty of people who brought it to my attention back then too) is that there are very very few tasks in general building and remodeling that productivity isn’t effected by crew size.

While (I used to) hang doors all the time and I still recall my own personal solo record of 17 in an eight hour day back in ’96 I also recall that I almost killed myself doing it and it took me days to recover from it so while I might have been ultra productive that one day I sure the days that followed were below average performance.

Regardless I mentioned above that while I personally see hanging doors as a solo carpenter activity (I could be wrong about that) I really see it done most efficiently by a two man crew so that on those occasions where you need an extra hand you don’t lose you productivity because your struggling to physically.

Despite what Walt Stopplewerth and the HomeTech school of thinking people seem to be advocating regarding using a one man crew I’m not at all convinced it’s the most productive way to get things done.

From Home Techs Frequently Asked Questions:

What Crew Types Do You Use When Determining Labor Costs?

The simple answer is ‘all types of crews’. We do not believe that the price for a specific amount of production changes depending on the crew mix. Let me give you an example. One contractor uses an experienced lead carpenter to do framing by himself. Another uses an average carpenter with a helper. The first contractor pays the lead carpenter a total of $30 an hour and he finishes the job in 10 hours. His cost is $300. The second contractor pays his carpenter only $22.50 an hour and the helper $15 an hour and they finish the job in only 8 hours. His cost is also $300. Both companies used different crew mixes but the per unit or per job cost is the same.

We have found that with stable, profitable companies, crew mixes do not substantial change the unit costs. So if you are paying your employees what they are worth, 100 square feet of wall framing should cost you the same whether you use a one or two man crew.

One problem I have with that is it just doesn’t quite work out that way in the real world. While not true of every task there are a lot of gains to be made at time by just having that extra time or perhaps it’s better stated that the extra time it takes to do a particular task all by yourself can be eliminated by having that “extra hand” on call from time to time.

But again,… it depends upon the task. And it certainly worth keeping in mind what is spoken about in software development circles as Brookes Law: “adding manpower to a late software project makes it later” which also has it’s humorous corollary “Nine women can’t make a baby in one month.

TheMythicalManMonthIn his book The Mythical Man Month Brookes himself stated that that “law” was a “outrageous oversimplification” he gives two reasons why it is so often true (from Wikipedia Brooks Law):

  1. It takes some time for the people added to a project to become productive. Brooks calls this the “ramp up” time. Software projects are complex engineering endeavors, and new workers on the project must first become educated about the work that has preceded them; this education requires diverting resources already working on the project, temporarily diminishing their productivity while the new workers are not yet contributing meaningfully. Each new worker also needs to integrate with a team composed of multiple engineers who must educate the new worker in their area of expertise in the code base, day by day. In addition to reducing the contribution of experienced workers (because of the need to train), new workers may even have negative contributions – for example, if they introduce bugs that move the project further from completion.
  2. Communication overheads increase as the number of people increases. The number of different communication channels increases along with the square of the number of people; doubling the number of people results in four times as many different conversations. Everyone working on the same task needs to keep in sync, so as more people are added they spend more time trying to find out what everyone else is doing.

While Brookes is talking about software development I am sure intelligent builders and remodelers can see how this applies to building and remodeling projects too.

The answer I think is just don’t throw bodies and resources at a project and expect it to get done faster. You need to design and engineer the work flow process to succeed.

In another article from the Home Tech web site on the Lead Carpenter Method: Home Techs Lead Carpenter Concept Overview:

Studies of remodeling have shown that the one-person crew is the most efficient: that first person is 80%-100% efficient, the second is 25% efficient, and the third is minus 5%.

While I never been a fan of the one man crew idea for safety reasons alone I also have to wonder,…what are those studies? This is one of my favorite pet topics and I have found tons of studies and papers on productivity over the years and I have never seen on that states that conclusion. Hey Home Tech how about a footnote?

My thinking,….well it depends upon the task and how that task is organized and planned in relationship to other tasks.

While it is possible (I’ve actually done it a couple of times) one man alone cannot (or should not ) really install a shop built stair by himself. But then again after the stair is installed to get the newels installed and the balustrade ready for installation doesn’t take two carpenters. But then again when it come times to install that balustrade once all the prep is done two or three hands makes short work of that process where one person would struggle with it for a while with a lot of wasted time and effort.

It makes perfect sense for the stair installer to have two other carpenters working on a non critical chain/path activity such as maybe running trim or hanging doors that he or she can interrupt and call away for assistance for a few minutes.

However (and while its unlikely in this sample case I’m making) if those other two carpenters are instead working on the critical chain/path task then calling them away slows and delays the completion of the whole project so the stair installer in interest of getting the whole project completed in the shortest duration of time is then better off , or the project is better off, with him or her finding a way to do it alone.

In other words it depends upon the overall project’s organization and logic.

So getting back to the point I’m looking to gather some thoughts on whether there is a big enough difference in productivity between a solo trades person and a two person crew that we need to really to go nuts paying attention to that when were estimating and then scheduling? When does it matter and when doesn’t it?

How do we “Think Lean” about this?

What are your thoughts?

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The Little Lessons we get hit with every day in Lean, TOC, & Six Sigma: Lesson 1; Poke-Yoke (Mistake-proofing a process)

Purple Curve EffectLast night I bought and downloaded Jeff “SKI” Kinsey’s e-book Purple Curve Effect: Throughput on Command (hey it’s just $2.00, what a deal!) and picked up on this little lesson in Lean Thinking that had a touch of Six Sigma to it too.

This little lesson came up as I was printing it out. I like to print out documents so I can read, highlight, and write notes in the margins (see Looking Back on My Thoughts On Reading from August in ‘97 for more on that). Generally speaking if whatever I’m printing out works out to be about 15 pages or more I’ll bind them up using A GBC hole punch and presentation binding comb setup I have.

Well I went to print out SKI’s book and given that it’s 185 pages both to make the book less thick and to save on paper I would print the odd pages first and then flip the bundle of printed pages over and print again only this time printing the even pages and then I have the book in front and back printed pages.

Well I printed it all out and as I was getting set to bind it up I noticed something was wrong with the page sequencing starting around page 80. Instead of page 85 having page 86 printed on the backside it had page 84. What the h….?!?

I quickly discovered what must have happened. Printing through the first run of just the odd pages at some point the printer grabbed two sheets of paper rather than just one so in that first run I had a uncalled for totally out of place blank page. When I printed it through for the even pages everything printed out just fine until I got that blank page which would then throw the rest of the printing page logic off.

That’s not a big deal right? I can just print the pages from 85 on again. And what is the lesson in Lean and Six Sigma in all of this?

Well as soon as the problem arose I realized there was a simple Lean term or tool for a procedure that I ignored and didn’t use that had I done it, it would have prevented the problem from ever occurring. The lean term is Poke-Yoke which is “a method of making process robust and mistake-proof”. What was the Poke-Yoke? Often printed on the packaging the paper comes in and certainly in the printer manuals for our printers in mentions that we should bend back the stack of paper and flip or leaf through it to separate the pages before loading the paper into the printer.

A simple second and a half procedure I just simply ignored wasted some 40 sheets of paper, a little ink and the entire process of printing out the e-book which should have taken maybe 7-9 minutes ended up taking me four to five times longer that it should of had. I had to discover and then diagnose the problem and then find where I had to restart the process from and then restart and repeat the process again from that point.

A little lesson learned….


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As part of the continuing Theory of Constraints Learning Process and the Lean Journey

As part of the continuing Theory of Constraints Learning Process and the Lean Journey my companies and the companies I consult with are on, I came across another interesting (PDF) article as part of some research I was on. The article that I found dusted off recollections of a topic that appeared in the Journal of Light Construction Business Strategies forum last winter entitled Is Our Industry Antiquated?

The contractor who started the topic off first wrote:

Just watched a TLC program about the largest Cruise Liner ever made, Voyager of the Sea. From start to finish is was completed in two years. 1020′ long (3 + football fields in length) , 157′ beam, and 214′ high (20 – 25 decks ?), and it’s not the longest ship either; an oil tanker is about 1600′ long, which is more than 5 football fields in length. And this cruise ship is like a hundred houses in one.

My point, and I guess question, is if such a ship with the tremendous challenges to build it, yet accomplishing that task is only 2 years is incredible compared to the result of a huge high end house that would take us two years. Seems what we do is nothing compared to what’s being done in ship yards as far as efficiency of resources.


Royal Caribbean Cruises – Voyager of the Seas

For the most part I thought the responses from other contractors to the topic were really either lists of excuses as to why we can’t do that in our industry:

"Yeah Sonny, but does their client keep changing the color of the ship? or the locations of the windows? or the cabinetry?") or explantions as to

Or explanations as to why they were able to accomplish such a tremendous production effort because they had the extra money to spend on it!!

"Am I antiquated with regards to that? You betcha. Does it cost my bottom line? Nope. We all have room for improvment in just about anything we build. Is that the point you’re trying to get across? Could I better keep track of inventory? Sure, by hiring someone like the shipyards do just to do that all day. Can I keep the men better supplied and ahead of the game at all times? Sure, I just need someone to oversee that on a full time basis. Can I afford these luxuries like the union ship yard can? No way. Do I have a crew of tool men keeping track of who needs what and keeping all the tools in repair at all times. Nope. The ship yard does. They can afford it."

Wow talk about really not seeing the forest through the trees!

However in defense of some of some of my fellow contractors there are some out there who I think either "get it" or are beginning to "get it".

Builder Allan Edwards wrote:

"If 80% of the projects are coming in behind schedule, then I would say that’s the norm. Isn’t’t insanity described as doing the same thing over and over and expecting different results? Seriously, scheduling is something we should give more attention to. "

And contractor Rick Westmoreland wrote:

"Of course, 80% of the schedules could be unrealistic to begin with."

And Estimating Consultant Bob Kovacs wrote:

"The benefits of fast-track are incredible if it’s done correctly."

Looking back at that topic I was surprised to notice that I never said what I really wanted say there in response to that "They can afford it." comment was essentially what Bob Kovacs was getting at in that the Because the work is well designed thought out and is done in a continuous FLOW process it is by far LESS EXPENSIVE! It’s saving money! The truth is we can’t afford not to do what they are doing!

We (our industry as a whole) have to stop making excuses as to why we can’t innovate and improve if we are ever going to fully realize the potential for achieving and harnessing greater profits.

Well, getting back to where I started the PDF article I discovered today is entitled TOC in a Commercial Shipyard by Daniel P. Walsh from the website. Well worth reading.

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Out of Control

Interesting,… what I was looking for was some infomation on the Last Planner System™ and Hals comments in blog of Wednesday, October 02, 2002 First Thoughts on Control were both along the lines of what I was looking for and it got me thinking progressivly towards some other ends too. Talking about Kevin Kelly and his book Out of Control: The New Biology of Machines, Social Systems and the Economic World Hal wrote:

“Kevin traces the development of modern control to Norbert Weiner. Young Norbert was raised to be a genius. His father wanted a Nobel Prize in the family. His work provided the foundation for cybernetics. It started when he joined the effort to make uniformly thick sheet metal. The stakes were high because uniform feedstock would allow machines to make car parts — fenders, auto bodies etc. Three variables were obviously involved – the heat of the metal, the pull tension and the roller setting. But no one had found the magic relationship that could assure a long uniformly thick roll. Norbert cut through the problem. He showed with a simple mechanism that controlled the last variable produced the desired result as long as the other variables were within in a range. Being “right” didn’t matter as much as the ability to adjust quickly. His device detected the thickness of the metal just past the rollers adjusted them in response. Controlling the last variable with rapid feedback was all that was required as long as the other variables were within some range.

I was struck by how well the Last Planner System™conformed to this rule. Work is made ready as it moves forward to action and only released to certain criteria….

…There is more to say about control of more complex systems but the first rules are clear. Control the last variable while keeping the others within some range, and tightly couple the detection of variance to the control gate.” (my emphases)

More good stuff and very apropos. Just the kind of stuff I was looking for today.

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