Hi,
I am wondering what the best method is for calculating the total square feet in a single family dwelling? This is a two story log home that is not square but irregular.

Do vaulted ceilings, stairwells and storage rooms with electric count?

I think Fannie Mae set the standard by using ANSI 2003.

The house was bid on 4000 sq ft and now I find out it is actually 5400 sq. ft.

How can I be sure that what I am being told is correct?

Happy New Year!

Thanks for any replies.

Greg


[This message has been edited by mustangelectric (edited 01-03-2005).]

well the simpliest and most time consuming idea is to measure every room and add that up if you allready bid this at 4000 and it is really 5400 i would not chance it i would just measure every room
who knows it could be over 6500 sqft

Hello Greg, I don't quite understand your question. Is there something beyond 220.3(A) that needs to be taken into consideration?

The vaulted ceiling/s would not be an issue, the stairwells and storage rooms (used spaces)would be part of the floor area computation.

Roger

Hi,
The code says drop the garage but I bid based on TOTAL SQUARE FOOTAGE. Why the garage would be excluded is not clear but I have never seen but one garage that did not have lights, recepts etc. As a matter of fact most garages nowadays serve as the mechanical room for equipment like electrical, HVAC and garage door openers.

I read up on ANSI and they include the stairwell and vaulted cielings above 7 foot.

I measured from a drawing the exterior walls because even dead wall space is counted as well as any room that has an outlet.

The shape of the house is not totally square so I broke it up inot sctions that I could figure.

I know that realtors and banks have different methods.

I realized that something was not right by the amount of wire that I already used.

The house had a 200A service already installed.

It is ALL electric with dual 60A heating elements, 40A AC, electric HW and electric range and 240 vac micro, spa, and..there are already over 25 recessed cans and over 20 regular lighting outlets. Another concern is that the service is too small.

3 watts per square foot on lighting alone is 60A.

-regards

Greg

I think a 200 Amp service for this size home with all electric is too small. My rough calculations come to around 215 Amps and you would be well served to upgrade to a 400 Amp Service.

Hi,
There was a 200A CSED mounted on the pole when I showed up.

It is an underground service that is 125 feet from the house.

I installed a 200A main panel and a 100A sub panel which are almost full.

There is Electric Heat two 60A disconnects, Electric Range 50A, Electric HW 30A, 240V Micro 20A, Dryer 30A, AC 40A, Dishwash 20A ,Disp,ref and tons of lighting and 5 ceiling fans at 60A.

What do I do now? There is no way they will pay to upgrade now.

Am I responsible for this mistake?

-regards

Greg

[This message has been edited by mustangelectric (edited 01-03-2005).]

Greg, the smaller load of heat or A/C will be cancelled, the range will only be 8 kw, there is a better than likely chance there is not a problem.

Can you post the actual fixed loads so we can have a calculation party?

Roger

Boy am I glad I'm not you! But seriously, here's my unsolicited opinion:
I have 4 rules that there are no exceptions to.
1)Never ever ever ever ever bid a custom home by the square foot.

2)Never wire a new house where someone else has installed the service entrance without a detailed written agreement full of disclaimers pertaining to the service size, location, and equipment.

3)Never agree to finish wiring a house someone else started without another long, detailed written agreement full of disclaimers.

4) Never accept a job on someone else's service calculations and electrical lay-out. Not even the architect's.

I don't know what the answer here is for you in this situation. If you just finish the job as is it will probably be your name that is mentioned every time their is a problem and there could be many if the service is inadequate. You could make things right out of your own pocket and count it as an expensive education. It may sting but it will be cheaper in the long run than a bad rep. A lot depends on who you are working for. Is it the homeowner or a GC? I would suggest that you run, don't walk to who ever that may be and do some explaining and negotiating. Good luck.

I get 207 amps figuring 5400 sq.ft. and what you listed and that's with the minimum 2 SA branch circuits.

Hi,
Thanks for the replies. The HO says the bank says the actual square footage is 4800 but I am guessing this is Heated living space only. The garage is not counted in the NEC so I will have to find out if that is in there or not.

80% load is all you are allowed right?

I will have to measure the house myself to be satisfied.

Fred,
This was a brand new house. There was a NEW 200A service on the pole that was basically used for temp power. The HO had this installed before we ever met. I bid all homes by the sq ft for basic wiring only. Anything above what is required is extra and I give a list of what those cost before hand.

I see no need for special provisions on a service installed on the pole. I installed a service lateral and a 200A main panel at the house. I am not responsible for the panel on the pole or the size of it.

There was no previous electrical work done on the house just at the pole.

There were no plans, no calculations provided everything was AS-BUILT. This is spelled out in my proposal.

The only problem I see is that if the actual square footage is 5400 then the loads will more than likely exceed what is allowed. Even if there is 4800 sq ft. I would still rather see a larger service.

Had I been asked I would have recommended a larger service based on just common sense alone. From a clean slate with no plans I could easily wire a 5400 square foot home with a 200A service. That doesnt leave much for future expansion though.

The worst case scenario here is that the service will need to be bumped up to 400A but I do not see where it is my responsibility.

Should I have told the HO that the new 200A CSED they had installed has to be replaced by a 400A service? I would have anyway had I known. Why would that fall into my scope of work?

I will post the actual nameplate ratings and the actual sqf as soon as I can get a 100 foot tape out there.

Do I really need to go out and measure each and every house?

You wont get any work around here if you do not bid by the sqf.

You may get one or two and I do but the bulk of my clients are shopping.

I used to bid by the opening then got griped at for that! How the heck are you supposed to bid a house?

I can almost guess how much material it will take and get pretty close to how many hours it will take and how many trips I will have to make etc but I have yet to come up with a solid method.

A takeoff is fine when you have a set of plans. But you may not win many bids using that method.

I am a sole proprietor.

Thanks for the replies..and suggestions..

-regards

Greg

[This message has been edited by mustangelectric (edited 01-03-2005).]

[This message has been edited by mustangelectric (edited 01-03-2005).]

There sould be a set of archetural plans for the house. Some one has those for permitting purposes to build the house structure. This is usually where you can determine the sqft before the house is built.
That is what I base my quotes on. Any additional building get additional work as a change order.
An example is plans calling for an unfinished basement not counted in the living space sqft calcs. Frequently these basement become finised before the HO moves in or shortly there after.
Using those a page plans you can design the electrical system on a per hole basis the divide by sq ft for your bidding to GC's and by keeping the design be able to show what is and is not included in yor bid.
It is a bit of extra work to set up but it sure helps when you have to get change orders and/or extras.

Greg,

If you took the area off of the drawings and made accurate calculations from those drawings then you can not be over what you figured unless the drawings were not accurate.

I just got back into wiring new homes and have been tracking everything about them. I can tell you everything about my history for this particular builder, cost per sq ft, labor per sq ft, sq ft per hour etc. When I bid to somebody else I have a good base line from which to estimate. However you have to watch when you get into custom because of expectations. You have to at least look into what the customer is going to expect. Look at what types of lighting and other fixtures are spec'ed. Make sure that the two of you are on the same page.

It sounds like the customer had one set of expectations and you had another. Go back over your contract documents and see what you told them, see what they told you, it may be a misunderstanding or it may be a case of misrepresentation on their part. Either way the sooner you address the problem the sooner it will be resolved, or not, but it won't go away at this point.

Good Luck
FRANK

Hi,
I do not think there was any intentional misrepresentation. I felt that everything was ok until I realized that there was more sqf than I was told. To be honest I never calculated the sqf myself before now.

I am still trying to decide how to calculate it. Only two sides are unbroken the other sides are oddly shaped. SQF is calculated by L*W but what if the structure is not perfectly sqaure? I just want to calculate total sqf inside the exteriro walls.

I think the calculations will come out ok but I will have to get the actual sqf to be sure.

thanks

greg

If you are talking about a service, no, the 80% factor does not apply to service calculations.

For some reason, many electricians believe that the 80% factor applies to everything, but it does not.

The "80% rule" only applies to continuous loads (3 hrs or more) and in a dwelling unit they will be few and far between, if you have any at all.

Peter D.

[This message has been edited by CTwireman (edited 01-03-2005).]

x

[This message has been edited by Jps1006 (edited 01-03-2005).]

Can you break it down into squares and have triangles left at the irregular areas? Then it is base times height divided by 2. Base is any side. Height is measued from the base to the angle (tip) on the opposite side.

Hang on, let me find a link and edit this..........

http://www.mathleague.com/help/geometry/area.htm#areaofatriangle

sorry about the double post

[This message has been edited by Jps1006 (edited 01-03-2005).]

I frequently get plans to bid from with no electrical on them. I tell the GC or homeowner up front that I will draw on the plans what I am pricing and let them know I keep the copy I draw on. If they want the drawings to shop around the charge for design/layout is $500.00. The electrical contractors I know who bid by the sq.ft. estimate a job by the opening and divide their total figure by the sq.ft. The guys I have known in the past who actually bid by the sq.ft. are no longer in business. I should also point out that I do not do tract houses, I do custom homes. I did a few tract houses years ago and figured out that you had to sacrifice quality to make any money. I would rather work a factory job for wages than wear out tools and equipment as well as by body for the same hourly wage. I too am a sole proprietor and have been for 25 years. I don't see how "from a clean slate" you could "easily" wire a 5400 sq.ft. house with all you listed on a 200A service. Do the load calc. It's over 200A. Sooner or later it's going to get cold and both of those heat banks are going to kick in. What if supper is in the oven, clothes are in the dryer and someone is taking a hot shower when that happens? At 125' between the pole service and your panel, don't you think VD will be a factor? I hope the panel you put in had a copper bus. I was called to a house 3 years ago on Christmas eve that had lost their electric heat. It was a new 5800 sq.ft. house going through it's first winter. Total electric. 200A service with a 200A MB 40 ct alum bus panel. The (2)60A breakers for the strip heat had the alum bus burned in two.

Hi,
Thanks for the reply. Fred, your putting words in my post..I said I could easily wire a 5400 sqf home from a clean slate...I never said that I would use the same equipment and devices used in this post.

Relying totally on electricity where I live is insane. Sometimes the power will go out for days due to severe storms and ice. I would either use gas/propane for my heating and cooking, hw and dryer..

voltage drop on a 4/0 cable from 125 feet is less than 5%. I use all SQ-D equipment. Never had a single problem in 27 years. I have seen single pole breakers stop tripping though.

The total square foot on the house is 4800 sq feet not including the 790.5 sqf ft garage so I do not see any problems.

You said.
"The electrical contractors I know who bid by the sq.ft. estimate a job by the opening and divide their total figure by the sq.ft. The guys I have known in the past who actually bid by the sq.ft. are no longer in business."

Lets consider that a moment...although you did not give all the information I need to compare I can assume that you will charge a certain dollar amount for each opening. It doesnt even matter what you charge per opening.

If you have a $10000 estimate and a 5000 sq. ft house and you divide that I get:

10000/5000=2

Is that $2? You got me.

If you have a $20000 estimate and 5000 sq. ft house you will not get the job so it doesnt matter.

Please enlighten me as to how this works so that I may understand you more clearly.
So far I can not imagine how this would work even for a sole proprietor who can charge less than a business with 5 or more employees if they want to.
--------------------

Say you have a 5000 sq. ft home and estimate the cost at $10000 then divide by the opening...say there is 100 openings, then you are charging $100? More openings and you get even less. I dont get it.

Another way I can think of..

If a house has only 100 openings (just an example) and it is 5000 square feet then according to my example I get 5000/100=50. So are you charging $200 per opening? Still dont see it.

Why would you divide anything?

Try the per opening method..

If I use $35 per opening that is $3500 based on 100 openings.

If I use $70 per opening that is $7000 based on openings.

I would have to charge $100 per opening on a 100 opening home to match the starting point on a per sqf bid. I can imagine the look on a clients face when you say that the cost is $100 per opening!

Even if there was 200 openings that is $20000 and you can't get $20K to wire a 5000 house where I am at even if it is a custom.

---------------------------

Lets look at my method:

$2 per sqf for required wiring and standard appliances. Anything beyond that is extra and I do not pay for fixtures I will only install them if they are on the job. I provide all recept, switches, smokes, phone jacks and cable tv outlets. If I have to return for any work it is $45 per hour. This includes a couple phone jacks and a cable tv outlet in the living room, and all bedrooms. Cat 6 cable is extra and I also wire the garage door opener controls as well. I include a service with the $2 sqf but not the conduit to the poco. If it is overhead then I will throw that in. All my work is warranteed for a year or more if I decide.

So given 5000 sqf home I get:

5000*2=10000

Recessed cans go for $65 a peice and I always end up with a few thousand dollars in extras on a large custom home. I am happy. For now I do not see a better method.

I have even figured up material and manhours to do the job and that is about the best method besides per square foot. Even if you figure material and manhours you will come out better on per sqf bids I think.

I have done all kinds of bids, turn key, by the opening, by the sqf, actual cost, etc.

I am sure there are more opinions on this. I use a little program called the National Electrical Estimator that is pretty good.

Thanks for the comments...

-regards

Greg



[This message has been edited by mustangelectric (edited 01-04-2005).]

I don't necessarily see a problem with Mustang's method. Whether by the opening or by the square footage, there is give and take on both. By the opening, you do better on multigang switches and countertop outlets, but not as well on openings in a garage with a tall ceiling. Square ft. you do better on a large great room with few walls, but worse in small bedrooms with lots of wall space. Like he says, the square foot number just gives him code minimums, if it's not required by code, it's extra (am I understanding that right?)

Then the custom stuff gets counted up at the per opening price right?

Some might say "well why not just count the whole job by the opening?" But it sounds like you're saying you get a better base price your way.

Bottom line, what's most important is the bottom line. As long as it pays the bills and leaves enough left to make it worth the hassle.

Hi,
I seem to be making more money using the sqf method. I am not saying that if i get a room addition or a remodel that I do not bid a lump sum. These jobs are usually either hard dollar or pretty tight depending on circumstances. I have seen them go both ways.

But in my world there is a lot of competition out there and sometimes you see competition and sometimes you dont. I have seen as low as a buck seventy five for residential. For instance I get a lot of call from private individuals and they very rarely know anything about what they need electrically. They just want the minimum stuff. That is fine I will do any required job for $2 a sqf. then when you add the extras, like recessed cans, dimmers, undercabinet lights, huge pendant lights or a light in every closet and extra bath lights and outdoor lighting, extra cable and phone outlets, the list goes on.

I charge $65 per recessed can, $85 for a remodeler, $125 for flood light outlet, $45 for a cable outlet and $55 for a voice/data outlet, $45 for power outlet, ceiling fan outlet with dual switching is $125, Switch outlet single $45, switch outlet three way $55, and switch outlet 4 way $65. A 240v circuit is an extra $200 and if it is GFCI it is $350. Arc fault is $65 per outlet and so is a GFCI. Extras add up pretty fast.

If i get $13000 out of a job then $2500 may go to material, $300 for gas, and the rest is in my pocket. I may spend 40 to 50 hours total on a 5000 sqf home. So that is :

2800-13000=10,200

10,200/50=204

$204 dollars an hour is good money anywhere!

If I take $20 per hour of that and put back into my business and take out for my taxes then I figure I will stick with my method.

I am booked up till next year right now! I get most of the jobs I bid on.

-regards

Greg

Thanks for the replies...

-regards

Greg

[This message has been edited by mustangelectric (edited 01-04-2005).]

What happened to the load calculation discussion?

Roger

Roger,
I found out from the appraisal that the HO submitted that the actual HLA is 4800 sqf.

I will post the nameplate ratings of all the equipment on the project that I can get to.

Per the NEC the garage is not counted ( i do not know why they would not count it).

I am curious to know where this ALL ELECTRIC house will come out.

I will post the data this afternoon.

The original topic was how to determine the sqaure foot. I still never got but one solid answer! I ended up blocking it off from the building plan I was given it list the dimensions but as I said it is irregular so it was a jobjust coming up with the sqf.

I guess from now on I will look closer at that.

I may have been leaving some bucks on the table!

I thought the load on a panel is was restricted somewhere? I am almost sure it is.
-regards

Greg

Hi,
NEsparky, there is no zoning or permits where this place is.

There was a building sketch but no electrical etc just floor plan.

thanks for the comment

-regards

Greg

No wonder they call you Mustangelectric!

Giddyup!

Hi,
Coastal what is wrong you sound skeptical? It doesnt always work out that way but I would say that is my average. 60 hours on a job would be a lot.

The most important part of any electrical job is to get paid!

The second most is to PLAN! Planning is a big part of the job.

Knowing what needs to be done is important.

Knowing the NEC and how it pertains to residential work is important.

Having everything you need when you need it is important.

Having the right tools is important.

Having experience is important.

I used to wire a 1200 sqf house in a day or day and a half at the most!

That was when I was in my younger days.

I am not a quick as I used to be but I use my head a lot more.

I always try to use three conductor cable and I use seperate circuits for light and outlets. Most all of my lights go on Arc fault and I share bath circuits.

I use a lot of gfi outlets.

I try not to use any 3 ways or 4 ways if possible.

First I put in the service and the grounding.

Then I lay out my boxes and nail them up, then i drill out my holes using a 7/8 bit. Then I put up all the stuff in the ceiling like ceiling boxes , fan boxes and recessed cans as well as smokes and doorbell. Then i pull all the heavy stuff. Then i will run the lighting circuits. Then the outlets. Then run all my home runs.

I cut switch legs on a 45 and bend the ends of power...that makes it simple...mark everything at the panel as I run it.

Then I will make up what I can and test ALL OF THE RECESSED CANS!

Once sheetrock is up and paint is on then i come back and trim out and put up lights.

Now it doesnt matter how fast i do it, excpet when the insulator is crying to get in! Besides there is nobody but me to get it done!

Loads of fun!

-regards

Greg



[This message has been edited by mustangelectric (edited 01-04-2005).]

All due respect, I think the $204 per hour is highly misleading.

What about taxes, insurance, cell phone, vehicle depreciation, vehicle insurance, vehicle maintenance, tools and supplies, unbilled labor (time to get materials, time for billing and estimating), permit fees (if necessary), time to apply for permits, travel time, etc etc.

Factor all that and whatever else I forgot and you are not making $204 per hour.

Peter D.


[This message has been edited by CTwireman (edited 01-04-2005).]

Not skeptical; simply bemused!

Just visualizing a 5000+ sq. ft. home with a little 200 Amp meter can outfitted to the side of the garage brings a smile to my face.

My typical 5000+ sq. ft. home consists of 90+ recess cans, 2 Master bedroom Suites, 6 Guest bedrooms, 2 Media Rooms, Game Room, Elevator, 4 zones HVAC (20-30KW), 4 water heaters, 2 whirlpool tubs, 2 wet bars....(taking deep breath)...
4 kitchen circuits, 2 microwaves, 2 dishwashers, disposal, wine cooler, instant hot, ice maker, 2 cooktops, wall oven, under cabinet and cove lighting.....
(another breath)....
Swimming Pool, Hot Tub, Tiki Bar, Sauna, Steam showers, 600 Amp Service with CT cabinet and switchgear....etc. etc.

It takes a whole herd of "Mustangs" to wire these rascals in a week!

Hi,
Coastal how the heck do you fit all of that in 5K sqf?

My clients are frugal!

I just figured up everything in the place, here is a list:

Electrical Survey: XXX Residence
Item-Quantity-Watts
Recessed Light-40-4 kW
Ceiling Fan-6
Light Outlet-19
Vent Light Combo-3
Vent Fan-1
Single Pole Switch-52
Stack Switch-8
3 Way Switch-8
Receptacles-62
Porch Lights-10
Bath Bar Light-3
Telephone-10
TV-9
Smoke Detector-7
Sconce Lighting Outlet-5
GFCI-16
200A Service-1
100A Sub Panel-1
240 VAC Outlet 20A-1-4.8 kw
240 VAC Outlet 30A-2-10 kW
240 VAC Outlet 40A-1-AC
240 VAC Outlet 50A-1-8 kW
240 VAC Outlet 60A NA
Flood Lights-3
Decorative Lighting-2
Switched Outlets-3
Dimmers-10
Fluorescents-3
Closet Light-8
Spa-1
Dishwasher-1
Refrigerator-1
Disposal-1
Under Cabinet Lighting-3
Chandelier-2
Door Bell-1
AC-1-9.6 kW
Heat-1-28.8 kW

Lot of stuff but not near as much as you!

4800 SQF. No nameplate for heat so I used the 60A rating for each heater. The ac is 38A max.

-regards

Greg



[This message has been edited by mustangelectric (edited 01-04-2005).]

I just finished a 5200 sq.ft. custom home. It had 325 openings. By openings I count recepts, switches, light provisions as openings. I price a job at $35.00 per opening(steel boxes)plus $85.00 for each 240V cooking appliance, $75.00 for elect dryer.$2850.00 for a 320A. TV and phone are $30.00 an opening and OHD pre-wire(buttons, beams and recept) are $150.00 per door. I don't know how you could avoid 3 way and 4 way switches in a 5000 sq.ft. house. I work by myself and the 5200 sq.ft. house I just finished took me a lot longer than 60 hours to install the service, rough it in and trim it out. If you can do it, my hat's off to you.

Fred,
Thanks for the reply. It is interesting to see what kind of prices are being charged out there.

This is 4800 sqf. This house probably has 200 openings.

If you look at the list of stuff I installed you will see that it is not near what you described.

I forgot to mention that dad opened the trench and closed it too so that saved me some time.

The builder drilled all the exterior holes.

I think I will start charging for OH door controls..I like the way you think!

Not all jobs go the same!

thanks again.

-regards

Greg


[This message has been edited by mustangelectric (edited 01-04-2005).]

[This message has been edited by mustangelectric (edited 01-04-2005).]