Pricing Materials for Electrical Budget

[AlabamaGuy]

I'm going to finish my 30x40 this spring and I am pricing out materials to make a budget before I get started. I've got nearly everything priced but have been procrastinating on the electrical side of things. I'm going to have a small apartment in the shop so my electrical demands will be as followed:

Window Unit x 2
Welder
2 Post Lift
Washer/Dryer
Tankless Water Heater
Oven/Stove
Air Compressor
Typical Lights, switches, and outlets.

I'm thinking a 100Amp service box will be enough, but I'd like to verify that. Also looking for a rough estimate on what wire and materials I should plan on using. I don't forsee any complicated wiring as I'd like to keep it simple enough to do myself and then pay someone for an inspection. Does that seem reasonable? I have done some simple wiring before, but no real experience. I am a good learner, however.

 

[sberry]

Get rid of that tankless water heater.

 

[Stuart in MN]

Tankless heaters are always a discussion point here but I agree with sberry. An electric tankless heater, particularly one that's big enough to handle a clothes washer will require a LOT of power for operation - probably more than 100 amps all by itself. I didn't see any mention of heating for the building itself...you are in Alabama so the requirements aren't as much as I would have in Minnesota, but I assume you'll have something in there - will it also be electric, or will it be something else (propane, natural gas, etc.)

 

[wyliesdiesels]

What is the HP rating on the compressor?

 

[AlabamaGuy]

I've read pretty good reviews on the tankless heaters, and it is more of a space saver than anything. a Washer running by itself or one person taking a shower is going to have that much of a draw? I'll look more into it, I suppose.
I don't have a compressor yet, as I don't have a place to put it out of the weather.

As far as heat, the window units are Heat/AC and I also have a wood burning stove to go in it.

 

[Norcal]

If you want a tankless WH go gas as electric models have very large power requirements.

 

[Jim greengo]

Figure $4000.00 for materials to wire it,that way you've got plenty of padding.

 

[AlabamaGuy]

If you want a tankless WH go gas as electric models have very large power requirements.

That's a good idea, I'm having a tank set hopefully in a few weeks.

Figure $4000.00 for materials to wire it,that way you've got plenty of padding.

Would you mind elaborating on this?

 

[alfredeneuman]

The smallest point of use water heater is made to run a lavatory sink and nothing more. 6KW@240V=25A, which is no match for a washing machine or shower
A standard clothes dryer eats 21A@240.
Even a small toaster oven draws at least 10A@120V

+Lights and Outlets+Compressor+2ACs+Lift+Welder, all on a 100 amp circuit?

 

[wyliesdiesels]

I've read pretty good reviews on the tankless heaters, and it is more of a space saver than anything. a Washer running by itself or one person taking a shower is going to have that much of a draw? I'll look more into it, I suppose.
I don't have a compressor yet, as I don't have a place to put it out of the weather.

As far as heat, the window units are Heat/AC and I also have a wood burning stove to go in it.

An electric tankless will **** down the juice real quick. Look at the electrical requirements for them. Some even require 2 branch circuits.

if you want tankless, gas is definitely the way to go. It will be far cheaper to run it on gas than electric.

 

[MattT]

I've read pretty good reviews on the tankless heaters, and it is more of a space saver than anything. a Washer running by itself or one person taking a shower is going to have that much of a draw? I'll look more into it, I suppose.

I'm running an 18 kw tankless and it does great with everything but filling a bathtub. Have to throttle the water flow a bit for the tub. I went with electric because propane would've cost more and been a lot more work.

Before you decide on tankless ask around locally to see if anyone has/had one. They're very sensitive to water quality. And check your power company doesn't do demand billing before you go electric.

And personally I'd go with a 200A service regardless. Shouldn't cost much more unless you've got to run a distance underground on your dime.

 

[MattT]

An electric tankless will **** down the juice real quick. Look at the electrical requirements for them. Some even require 2 branch circuits.

if you want tankless, gas is definitely the way to go. It will be far cheaper to run it on gas than electric.

My 18 kw is 2 circuits. Some of the larger ones require 3.

Here in the South there ain't much difference between electricity and propane costs. Can swing either way depending on what time of year you buy the propane.

 

[rpcraft]

Tank-less gas heaters are great but from every account I have heard a Tank-less electric heater is going to leave you disappointed if you get temps that stick around the 30's or lower. If you insist on sticking with it though look at a 200 amp box. The welder, oven and tank-less heater are going to be duplex 50 amp circuits on their own. Add in the dryer and compressor and you are already at 10 slots in that panel. It's not the amp load so much as available room for additional breakers. You just want to make sure and have plenty of open slots left for lights, outlets and expansion with solid 20 amp circuits for your window units that I would keep independent from any lines you will be running any other tools that have a high amp load, especially at turn on. The cost of the panel difference should be negligible in the grand scheme.

 

[TractorJeff]

18 kw heater is around 78 amps.

 

[rpcraft]

18 kw heater is around 78 amps.

Wow!!!

 

[AlabamaGuy]

Very good info, guys. I'll update my list to a 200 Amp box for sure. Is my major cost going to be in lighting and heavier gauge wire? I'm having trouble coming up with $4000 worth of supplies. But then again, I have no real experience on this front.

 

[SarcasticDwarf]

Also looking for a rough estimate on what wire and materials I should plan on using.

• Count # switches and type
• Count # receptacles and type (decide on #amps)
• Count # wall plates for switches and receptacles
• Count # outlet/switch boxes, type, and size
• Rough measure the length of wire you will need. I am assuming you are using NM(Romex). Add 1' every place you have a connection. Separate by type and gauge.
• Wire nuts (boxes), staples, tape, etc.
• Count and decide on fixtures
• Electrical panel - Note that you will probably want to match to whatever the house is using.
• Breakers (note that you will need AFCI/GFCI depending on location and these are NOT cheap.

12 gauge (sufficient for 20A circuits) is recommended for everything as a minimum by most around here, but you can get away with less if needed. How much you end up needing all depends on your design. For example, if you want a single dedicated 20A outlet on the far side of the garage from your panel, you are looking at about $50. The cost next to the panel would be closer to $40, but part of an existing circuit and next to the panel would be about $10.

Doing it yourself is entirely feasible as long as you are very careful about code requirements. The code requirements have changed considerably the past few years and most of the information on the web is wrong (ex: GFCI and AFCI requirements). There are a number of cheap books sold at hardware stores that are good sources of info (and come with pictures)! Edit: Did a quick search and it looks like Alabama is on 2009 versions, wtf?!

 

[rpcraft]

Definitely the wiring is going to add up. Typical 120 runs won't be too bad but once you start moving up to # 8 wire and higher it starts adding up fast. I'd focus on making sure your power stack is aligned down the wall with your heaviest offenders (I.e. welder, etc etc) so you can keep the runs as short as possible) I think it is easier to buy a 25 foot welding extension cable and move your cart around than run multiple outlets when you start looking at the space it takes up in the panel but it may cost less outright to run them in the structure. I think a standard electric water heater is going to be more efficient if you can find a place to hide it and it will definitely cost less for wiring than a tankless judging by what TRactorJeff posted.

 

[alfredeneuman]

Even without the water heater, the loads could be too much for a 100 Amp service, what with the stove, compressor, electric clothes dryer, welder, and 2 window ACs.

 

[rpcraft]

Even without the water heater, the loads could be too much for a 100 Amp service, what with the stove, compressor, electric clothes dryer, welder, and 2 window ACs.

I wouldn't look at it from that perspective. A lot of homes now days will have a 200 amp panel but have 300 + amps worth of breakers (mine does and it was wired by a licensed electrician, not me, lol). It's just not a factor to try and add up the amps because it is not likely everything will be on and pulling a full or maximum load at the same time.

A good example is how my compressor is on a 240V 30 amp circuit. While it is running under load it only pulls about 5 - 6 amps. When it starts it might pull 15 for about 2 to 3 seconds (if that long even) until it spins up.

The bigger picture is you just want to make sure you use a panel that has plenty of open space to distribute the circuits so you can spread the load and keep the high draw items dedicated to what they need to do.

 

[alfredeneuman]

That's why I said "could be" instead of "will be". It depends on how many things will be running concurrently.
Adding breakers together is no way to measure loads.

 

[nsula_country]

I vote to keep the tankless electric water heater.

I have two 27kw units. Each have three 40 amp circuits. 117.5A at full tilt, but don't think they ever modulate that high unless filling whirlpool tub. Never put an amp clamp on it.

We are in the deep south. Most of the year we valve one unit out. In the winter we valve the 2nd unit in so wife can fill whirlpool at wide open.

320A service. 3.5T heat pump, 2.5T heat pump, two 27kw tankless, double ovens, cooktop, dryer, and an *** load of can lights (around 50 throughout the house) that I still haven't changed over to LED. 200A would not cut it (80%=180A). Bill rarely over $200/mo.

Plan to put a 27kw tankless in shop also for hand washing, hot water power washing and beer brewing.

CT

 

[Norcal]

• Count # switches and type
• Count # receptacles and type (decide on #amps)
• Count # wall plates for switches and receptacles
• Count # outlet/switch boxes, type, and size
• Rough measure the length of wire you will need. I am assuming you are using NM(Romex). Add 1' every place you have a connection. Separate by type and gauge.
• Wire nuts (boxes), staples, tape, etc.
• Count and decide on fixtures
• Electrical panel - Note that you will probably want to match to whatever the house is using.
• Breakers (note that you will need AFCI/GFCI depending on location and these
  
  12 gauge (sufficient for 20A circuits) is recommended for everything as a minimum by most around here, but you can get away with less if needed. How much you end up needing all depends on your design. For example, if you want a single dedicated 20A outlet on the far side of the garage from your panel, you are looking at about $50. The cost next to the panel would be closer to $40, but part of an existing circuit and next to the panel would be about $10.
  
  Doing it yourself is entirely feasible as long as you are very careful about code requirements. The code requirements have changed considerably the past few years and most of the information on the web is wrong (ex: GFCI and AFCI requirements). There are a number of cheap books sold at hardware stores that are good sources of info (and come with pictures)! Edit: Did a quick search and it looks like Alabama is on 2009 versions, wtf?!

• AFCI’s are not required in shops or garages.

 

[MattT]

Tank-less gas heaters are great but from every account I have heard a Tank-less electric heater is going to leave you disappointed if you get temps that stick around the 30's or lower.

If you size it based on the published ground water temperatures then it won't keep up if your actual cold water temperature gets much below that in winter.

Is my major cost going to be in lighting and heavier gauge wire? I'm having trouble coming up with $4000 worth of supplies. But then again, I have no real experience on this front.

Heavier wire could be significant chunk depending on layout. If you can get the service entrance close to your big loads that'll help. Or maybe a sub panel will be cheaper and easier than running several heavy circuits across the building.

Lighting is "how much would you like to spend?". Ceramic lamp holders are $3 each but you can spend way more than that if you wish.

 

[SarcasticDwarf]

AFCI’s are not required in shops or garages.

The OP mentioned creating an apartment in the garage. I don't know enough to be certain, but what he builds seems to have the potential to no longer be considered only a shop/garage.

 

[sberry]

My neighbor bought a new welder. Will run on 14 wire and under 30A service. 100 will run all that except the tankless. If I was building new would be installing 200 unless there was a compelling reason not to.

 

[Jim greengo]

Very good info, guys. I'll update my list to a 200 Amp box for sure. Is my major cost going to be in lighting and heavier gauge wire? I'm having trouble coming up with $4000 worth of supplies. But then again, I have no real experience on this front.

Thats why I said there's a little padding in there,so if you dont end up spending that much you'll feel like you won the lottery.
Anyway if you're supplying the service coming in to the building plus all the materials for a well wired shop and an apt on top of it ,its pretty easy to get a couple thousand dollars in materials really fast.
And that's before you figure in wiring for hvac stuff and that electric tankless water heater you're talking about.
Then you start adding light fixtures,things can get expensive really fast.
Around here basic 2-3 bed room house with an unfinished basement can run $9000.00 to wire without adding a lot of extras.

 

[mike93lx]

The smallest point of use water heater is made to run a lavatory sink and nothing more. 6KW@240V=25A, which is no match for a washing machine or shower
A standard clothes dryer eats 21A@240.
Even a small toaster oven draws at least 10A@120V

+Lights and Outlets+Compressor+2ACs+Lift+Welder, all on a 100 amp circuit?

Ha! My entire house is on 100a service. 2 fridges, a freezer, dryer, 2 ton ac, window ac's, shop tools, etc. Nevet has been nor ever will be a problem.

Skip the point of use and get a reasonable tank unit. Should be no problem for an apartment and 1-man shop

 

[sberry]

Around here basic 2-3 bed room house with an unfinished basement can run $9000.00 to wire without adding a lot of extras.

I was wondering what the range was? Where is here? I tell people that are interested in the 10 grand range depending etc.
I kept track of one I did of my own and it was in that for a basic rewire with new 100A main.

 

[Jim greengo]

Omaha Nebraska area

 

[nsula_country]

I easily had $9k-$11k in MATERIALS when we wired our 2200 sq/ft home. Reason we used so many can lights was they are one of the cheapest lighting options for residential. They **** in a shop environment though.

Probably had at about $3k in electrical materials in the shop build and had about $3k in lighting fixtures and lamps (T8 fluorescent high bays).

CT

 

[nsula_country]

Ha! My entire house is on 100a service. 2 fridges, a freezer, dryer, 2 ton ac, window ac's, shop tools, etc. Nevet has been nor ever will be a problem.

Skip the point of use and get a reasonable tank unit. Should be no problem for an apartment and 1-man shop

I'm not saying that your wrong. 100A works for your application.

You must have access to NG or have propane cheap in your area to only need a 100A service for residential... Electric heat is common outside of the city limits. At least in our locale.

Only thing that is residential 100A in our area is manufactured housing that has gas appliances. All-electric manufactured housing have 200A panels. Even then, premade service poles come with a 200A can and a 200A feed thru panel. Just dig a 4' deep hole and pound the rod.

Tankless electric water heat isn't as evil as many of the viewers perceive. For us the biggest perk was that they take up 0 sq/ft floor space and only protrude 4" from the wall.

CT

 

[wyliesdiesels]

I wouldn't look at it from that perspective. A lot of homes now days will have a 200 amp panel but have 300 + amps worth of breakers (mine does and it was wired by a licensed electrician, not me, lol). It's just not a factor to try and add up the amps because it is not likely everything will be on and pulling a full or maximum load at the same time.

A good example is how my compressor is on a 240V 30 amp circuit. While it is running under load it only pulls about 5 - 6 amps. When it starts it might pull 15 for about 2 to 3 seconds (if that long even) until it spins up.

The bigger picture is you just want to make sure you use a panel that has plenty of open space to distribute the circuits so you can spread the load and keep the high draw items dedicated to what they need to do.

5amps? lol that must be a very small motor like about 1HP.

In-rush current is 4-8x FLC so it would be way higher than 15a.

My 3ton AC compressor pulls about 15a while running and 85-90a at startup.

 

[6768rogues]

I have a barn on my farm with a studio apartment in it. I use a small 19 gallon electric water heater that runs on 120V. One of us showers and then we wait a half hour or so till the other showers, but it will support two short showers. Then when we go to bed we run the dishwasher, and it has plenty of hot water. There is a 100A service to the barn with a 50A subpanel in the apartment. We use cold water in the washer, as we do at home. Detergent today does fine in cold water. We run lights, TVs, a refrigerator, washer, dryer, water pump, water heater, etc. and never lack for electricity.
My barn at home has no apartment, but it has two AC units, a stick welder, a wire feed welder, a lift, an air compressor, etc. It has a 100A panel and it never has a shortage of power. I suppose if I ran everything at the same time to maximum usage I could get close. I am not raising a car with one hand while I am welding with the other hand and while the compressor is running, on a hot day with the AC running but I think it would be ok if I could learn how to do all that at once.

 

[theoldwizard1]

An electric tankless will **** down the juice real quick. Look at the electrical requirements for them. Some even require 2 branch circuits.

How about THREE 240V 40A circuits.

Bottomless Hot Water!

Works well for LOW FLOW (< 2g/min), but like any residential hot water system, heat is lost through the pipes between the heater and sink.

 

[theoldwizard1]

I have a barn on my farm with a studio apartment in it. I use a small 19 gallon electric water heater that runs on 120V. One of us showers and then we wait a half hour or so till the other showers, but it will support two short showers. Then when we go to bed we run the dishwasher, and it has plenty of hot water.

Add a timer ! Shutdown at about midnight and start again about an hour before you want to use the hot water. Leave it off during the day but locate the timer bypass in a convenient place so you can turn it on manually.