I know nothing about electrical

[DZLFREK]

If you electrical guys were to build a house and a big garage and maybe a barn one day, what amp would you run to the main structure? Any ideas on how to outline the ideas?

Any and all help appreciated.

David

 

[ddawg16]

It's actually pretty simple math.....
Break it down by room and function....

Lights....each floor would 'typiclly' take two 20A breakers...you should never use that much...but you want to spread the risk...if one breaker trips, you don't want to be totally out of power.

I would say that one 20A breaker could handle 3 bedrooms....but I believe most people will use 2 breakers and have one of each in each bedroom....that is how my house is done....

Kitchen...if you have an electric oven...typically 30-50A at 220
at least 2 more 20A breakers for outlets in the kitchen...
Another one for fridge (typically on it's own breaker.....you don't want something else to kill power to it)
One breaker for dishwasher and disposal.

At least one breaker per family room.

Typical 1 story would be 100A min....I have 200A for my house...but 50A is for the garage.


For the garage....depends on what you are going to run....in most cases you typically don't have more than one thing on at a time....i.e., you don't run the welder at the same time you run the table saw....but with that said....assume you need power for a compressor, lights and then your largest item. At a min I would say 50A....with 100A giving you a lot more 'breathing room'.

 

[Aceman]

Paying someone to do a load calc for you is small potatoes in the grand scheme of things. What Ddawg mentioned barely scratches the surface and really isn't how the codebook shows how to do a load calc. Counting breakers doesn't determine service ampacity.

You oversize it by accident, you spend more money. You undersize it by accident, and you'll spend a lot more money fixing it.

 

[larry_g]

To outline what you need you have to provide the square footage of the house, all electric, or gas heat, air conditioning load, do you work from home and need extra stuff for a home office. Is the garage for parking a couple of cars, or is it heated and AC where you plan to do heavy shop work. Same with the barn you raising a couple of cows there or a heard of thouroughbred horses that need all the amenties of humans. Got a pool, outdoor lights, or a mirid of other things.

You have to provide a whole lot of information to get a semi close answer to your question.

lg
no neat sig line

 

[DZLFREK]

Thanks everyone for the replies. So here goes the detailed list.

Four bedroom house. 3300 square feet on a ranch with a 3300 square foot basement. The basement will have a lot of storage and probably half living space. The basement will be heated with radiant and the upstairs heated with forced air. Kitchen has two electric ovens, dishwasher and microwave. The range is gas powered. The laundry room is electric dryer with traditional washer. The garage is 26x41. I like a LOT of light (old eyes). I will not be running more than one heavy draw item at a time. The compressor will be in it's own shed attached to the outside of the garage. We hope to build a barn in the next couple of years, but for a few cows. Otherwords, besides lots of lights and maybe some auto tools, nothing crazy. No expensive horses. The barn will be heated radiant in slab. We also will have a modest green house. The greenhouse will be heated with forced air from the radiant system. All heat will be from a wood burning boiler. Hope this helps.

David

 

[walrus]

Thanks everyone for the replies. So here goes the detailed list.

Four bedroom house. 3300 square feet on a ranch with a 3300 square foot basement. The basement will have a lot of storage and probably half living space. The basement will be heated with radiant and the upstairs heated with forced air. Kitchen has two electric ovens, dishwasher and microwave. The range is gas powered. The laundry room is electric dryer with traditional washer. The garage is 26x41. I like a LOT of light (old eyes). I will not be running more than one heavy draw item at a time. The compressor will be in it's own shed attached to the outside of the garage. We hope to build a barn in the next couple of years, but for a few cows. Otherwords, besides lots of lights and maybe some auto tools, nothing crazy. No expensive horses. The barn will be heated radiant in slab. We also will have a modest green house. The greenhouse will be heated with forced air from the radiant system. All heat will be from a wood burning boiler. Hope this helps.

David

You need to know the actual equipment and their loads to do a real calculation. I'd guess a 200 amp entrance will do what you want, but why guess? Sit down with your builder and get a real calculation done

 

[DZLFREK]

I wasn't trying to circumvent the more logical way of doing things. Just trying to get a rough estimate so I don't go walking into the meeting with a white flag and take whatever I get as an answer. Thanks for the replies though!

 

[hidollartoys]

I would install a 200 amp service.

 

[Aceman]

Here's a halfway decent tutorial, start on page 32:

http://www.eandm.com/eandm/training/siemenscourses/load_3.pdf

 

[Underdog]

I would install a 200 amp service.

+1.........

 

[JBurgess]

The load calc will give you the minimum size.

Where I am at, it's underground, all in one service outside and utility furnishes conductors to meter. The cost of a 100 or 150 amp is nearly the same as 200 amp. The only reason to consider less than a 200 amp is if your costs are higher for the 200 amp.

 

[p_mori7]

400A.

200A for the house,

200A for the garage.