Estimates based on “per opening” vs “assembly”

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sw_ross

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I’m mostly referring to smaller residential and commercial projects that a small shop would be involved in.

I’ve mostly used the assembly method of estimating.
I haven’t used the per opening method before, but I could see some benefits of this method.

When I play around with this method I come up with a couple of questions...

Do you have various ‘per opening’ prices based on what the opening is?
I can understand a different price for GFCI opening versus a duplex receptacle opening, or standard toggle switch versus dimmer switch.

I’m assuming you don’t have an overall “average” price per opening that would cover ALL openings?
It seems like there would be too many variables.

I could also see using a hybrid version of the 2 methods. Maybe using the assembly method to come up with the initial estimate, and then a per opening list price for add-ons.
 
Also seems like there would have to be a per opening price that was based on the construction type and the wiring method used.

definitely gets into a lot of variables...
 
I’ve only heard that figure thrown around in residential. It’s a rough average that applies to everything. So, for example $100 per opening is for every single box and the customer supplies the lighting. There is a little more cost in the receptacle and switch openings, but what is saved on the lighting outlets gets applied to the service... it’s a rough figure, but in my experience, surprisingly accurate.


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sw_ross said:
Also seems like there would have to be a per opening price that was based on the construction type and the wiring method used.

definitely gets into a lot of variables...
Click to expand...
This method would work better for new construction only.
you could really get yourself in trouble on old work using a per opening price.
 
Jolted said:
I’ve only heard that figure thrown around in residential. It’s a rough average that applies to everything. So, for example $100 per opening is for every single box and the customer supplies the lighting. There is a little more cost in the receptacle and switch openings, but what is saved on the lighting outlets gets applied to the service... it’s a rough figure, but in my experience, surprisingly accurate.
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I'm thinking "per gang" to cover multi-gang device boxes and 240v outlets.
 
acin said:
Is an opening an outlet?
Click to expand...
Generally speaking, yes.

I'm suggesting that each single switch, receptacle, lighting outlet, or 120v hard-wired connection is considered one opening, each 240v receptacle or 240v hard-wired connection be counted as two, each two- or three-gang switch boxes be counted as two or three openings, respectively, etc.

Thus, a price per gang.
 
I’ve mostly used the assembly method of estimating.
I haven’t used the per opening method before, but I could see some benefits of this method.

Do you have various ‘per opening’ prices based on what the opening is?
Click to expand...

Those are one in the same...to me anyway.
How do you think you come up with an opening price?
A duplex assembly (as you know) is a certain footage of wire (emt, MC, romex), a box, ring, device, plate, ground pigtail, wire nuts...right?
I would build every assembly like this, then take the material/labor units and apply my rates, OH&P and there was my unit price.
I could make adjustments on the fly. When it became a job, I could print out a bill of material.
I know there a lot of guys who don't do this, and frankly I don't know how they come up with the even number unit prices (like $50, $75, $100/ea), unless it's years of experience, documenting each job and how much it was by square/ft and extrapolating unit prices that way.....or just wild-ass guessing
 
cdslotz said:
Those are one in the same...to me anyway.
How do you think you come up with an opening price?
A duplex assembly (as you know) is a certain footage of wire (emt, MC, romex), a box, ring, device, plate, ground pigtail, wire nuts...right?
I would build every assembly like this, then take the material/labor units and apply my rates, OH&P and there was my unit price.
I could make adjustments on the fly. When it became a job, I could print out a bill of material.
I know there a lot of guys who don't do this, and frankly I don't know how they come up with the even number unit prices (like $50, $75, $100/ea), unless it's years of experience, documenting each job and how much it was by square/ft and extrapolating unit prices that way.....or just wild-ass guessing
Click to expand...
I guess I think of an assembly price being a little more specific to what the device is...( GFCI, duplex receptacle, toggle switch, dimmer switch, etc) versus the per opening price being an overall average (of all devices)...?
 
I do assembly take off, but could see easily converting that to a per opening for each device type.

Here’s a few snapshots of a small house I started in July this year; I think roughly 1600 sq ft. This isn’t the whole take off. I typically do large custom homes, but I do a lot of commercial property work for this lady and she said her residential electrical on her spec homes bailed on her and I had a short break to fit it in.

3665c84f99f49590d98efa4423b781df.jpg

1647e3ff481948dafb865295ebc599fe.jpg

aee7b5e987b15aaab7783fdfc14aeb29.jpg

e576271dfa13c13ab38fd8d8597528fc.jpg



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brantmacga said:
I do assembly take off, but could see easily converting that to a per opening for each device type.

Here’s a few snapshots of a small house I started in July this year; I think roughly 1600 sq ft. This isn’t the whole take off. I typically do large custom homes, but I do a lot of commercial property work for this lady and she said her residential electrical on her spec homes bailed on her and I had a short break to fit it in.

3665c84f99f49590d98efa4423b781df.jpg

1647e3ff481948dafb865295ebc599fe.jpg

aee7b5e987b15aaab7783fdfc14aeb29.jpg

e576271dfa13c13ab38fd8d8597528fc.jpg



Sent from my iPhone using Tapatalk
Click to expand...
How were those unit prices determined.....Conest assemblies?
 
cdslotz said:
Those are one in the same...to me anyway.
How do you think you come up with an opening price?
Click to expand...
Yup. "Opening Costs" are based on Time and Material, just like a T&M troubleshooting job.
Difference is, "Opening Costs" utilize set Labor Hours and set Material Costs, but T&M and is generally open-ended.

Took me a little while to figure this out because the only information I would get from those I would work for is "this is an Opening Type job" and/or "this is a T&M Type job." The two are typically talked about as mutually exclusive, or at odds with one another, but there are overlapping similarities.

It also depends on whether your submitting an "Estimate" or a "Quote," the two having different legal ramifications.

I do "Opening Costs," but figure them based on a detailed "Time and Material Estimate." I list out the amount of labor hours and material for each opening type and calculate my "Opening Cost."

The use of the word "Estimate" legally allows me to keep it somewhat open ended and my Terms explicitly state that my "Estimate" may go as much as +/- 20%. I've been doing this for about 5 years now and have enough data to start figuring out averages and being more comfortable with actual, legally binding "Quotes."
 
sw_ross said:
I’m mostly referring to smaller residential and commercial projects that a small shop would be involved in.

I’ve mostly used the assembly method of estimating.
I haven’t used the per opening method before, but I could see some benefits of this method.

When I play around with this method I come up with a couple of questions...

Do you have various ‘per opening’ prices based on what the opening is?
I can understand a different price for GFCI opening versus a duplex receptacle opening, or standard toggle switch versus dimmer switch.

I’m assuming you don’t have an overall “average” price per opening that would cover ALL openings?
It seems like there would be too many variables.

I could also see using a hybrid version of the 2 methods. Maybe using the assembly method to come up with the initial estimate, and then a per opening list price for add-ons.
Click to expand...
The assembly method should give you an idea of where your opening costs should be. An opening cost is basically the same as the assembly method in my opinion, just broken down into various "opening types." Opening costs have to be based on something, unless your just pulling market averages from Google, and the forum already knows how I feel about that, lol.

It really all depends on how much math and how many variables you're willing to contend with. Some guys just pull a "market tolerable" average off Google and run with it to avoid the heavy lifting and get to making money. Other guys, like me, enjoy mathematics and want to know exactly where every red cent is going.

Even if you come up with a "GFCI Opening" it can vary further a thousand times over w/ variables such as "length of run, conduit size, wire size, outdoor/indoor, etc., etc." The solid opening price really only works for consistent opening types, such as 12 ft run between general purpose receptacles. No matter what, you're still going to find yourself toying with the specifics most of the time.

The best thing to do, IMO, is to have a solid pricing database for all of your materials. I'm still working on mine, but I have an Excel doc that I've been composing over the years that lists every single possible part and its' cost.

Also automation really helps, such as learning how to program in Excel.

Just be prepared to keep toying with it. You'll do one method, find a fault, fix it, find another fault, fix it, etc.
 
LarryFine said:
Generally speaking, yes.

I'm suggesting that each single switch, receptacle, lighting outlet, or 120v hard-wired connection is considered one opening, each 240v receptacle or 240v hard-wired connection be counted as two, each two- or three-gang switch boxes be counted as two or three openings, respectively, etc.

Thus, a price per gang.
Click to expand...
When utilizing the per gang method, don't you end up double charging for, say, conduit and wire? I utilize the per gang method, but only for device installation, which I price as a separate cost if beyond single gang.
 
Jerramundi said:
When utilizing the per gang method, don't you end up double charging for, say, conduit and wire? I utilize the per gang method, but only for device installation, which I price as a separate cost if beyond single gang.
Click to expand...

In residential, I’d say no. For switches, you’ve got a switch leg for every gang, and I typically utilize multi gang boxes as a place to get additional circuit branches out of. So basically two cables per gang.

Also the cost of boxes and plates aren’t equal per gang, so you could actually lose a little money if you don’t price it right.


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brantmacga said:
Also the cost of boxes and plates aren’t equal per gang, so you could actually lose a little money if you don’t price it right.
Click to expand...
I'm well aware. What I'm saying is... if you price say a "1-Gang Switch Opening" to include, for example, material wise, 10ft of 1/2" EMT, Fittings, 4 SQ Junction Box, Drywall Ring, Wire, etc... plus the Labor to install... and then just double that cost for a 2-Gang Switch Opening, you're double charging on some materials and some labor.

And I have a distinct feeling some a reading this and walking away whistling casually. Not Larry of course ;)
 
brantmacga said:
In residential, I’d say no. For switches, you’ve got a switch leg for every gang
Click to expand...
Depends on how your price it. For the Switch Opening, the way I do it, there is no Switch Leg, just a Hot and Neutral (possibly travelers).
The Switch Legs come in on the Lighting Openings.

But generally speaking, yes. There is typically 1 Switch Leg per Gang.
But that doesn't necessarily mean an additional 10ft of conduit and the time to install it per gang.

This is why I have a 1 Gang Switch Opening Cost that includes a single device, whose installation is priced separately within the opening cost.
Then I can just double or triple the devices without doubling the conduit, etc.

It also works well because now I have a separate device installation cost that I can use for just changing out existing devices.
 
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