Is a 200 amp main enough for a 2 story 20x34 plus a 12x20 lofted guest house?

[PunchAndJudy]

Looking at mains.  Old one needs to go.  Wondering if 200 AMP might be too small.  This is just me being curious.  I will sit down and do the calculations later this week.  Just curious about others opinions right now.

The 20x34 2 story will have an attic room also, so we will call it a 4 bedroom.  5 people will be living in it, and 1 person will be living in the small house.  Most of them will have jobs, though.  I know this isn't enough information.  Like I say, I'm just mildly curious right now.

Thanks.

[noklu]

Looking at mains.  Old one needs to go.  Wondering if 200 AMP might be too small.  This is just me being curious.  I will sit down and do the calculations later this week.  Just curious about others opinions right now.

The 20x34 2 story will have an attic room also, so we will call it a 4 bedroom.  5 people will be living in it, and 1 person will be living in the small house.  Most of them will have jobs, though.  I know this isn't enough information.  Like I say, I'm just mildly curious right now.

Thanks.

200 amps should be enough for the 20x34 2 story house (you might want the largest breaker numbers though) I would also make a 100 amp sub panel for the 12x20 lofted guest house.

[Native_NM]

I think it's more than adequate.  The sub-panel to the guest house is a good idea. 


http://www.constructionowl.com/electrical/100_or_200_amp.php

[TheWire]

Our log home is 3200 square feet with electric heat, electric hot water, electric range. There is a full 40 place main panel and 3 sub panels.  We have a automation system that monitors the current on the main service and the heating load and we never get above 100-125 amps. 

[Rob_O]

My first impression is you will be fine with a 200A panel in the main house feeding a 60A sub panel in the guest house. I'd like to see a load sheet before you start buying materials for the job

[PunchAndJudy]

Thanks everyone for your replies.  :-)

I'm thinking radiant barrier, passive solar assist for water heating in non-cold months and woodstove heated water in cold months,  ceiling fans, wood stove for heating, and flexible insulated ducting system (more efficient than conventional ducting) for AC in big house, thermostat set on 78.  CFLs.  No pool, no hot tub, no circus rides.  I will be doing my load calculations this week.  Feeling much more optimistic about it now.

[rocking23nf]

my new home has a 100amp service, its 2400 feet.  Unless your adding high amp equipment (pool,hottub, high end kitchen), its overkill in most cases.

[NM_Shooter]

200A is fine... don't go smaller.  Once you get the mains fed to the 200A, you will have plenty of service should you want to feed a sub panel to your guest house, barn, whatever. 

I don't know of anybody who has regretted going a little over sized!

[rick91351]

I would not go less than 200 AMPs and lots of slots. It is just handy.  And you don't have to fill them all up over night.  That sort of just happens.  And if it does not then you are not out a lot.  I have had to run a couple sub panels off mine and have never regretted it.

[Squirl]

I like the expression over at otherpower.  Houses don't use electricity, people do.  It's not based on square footage, but individual choices and habits. All houses I've lived in were 100 amp or less.  I am building an off grid house now with 30 amp.  I think you have the right idea about tracking were and how your electric loads will come from.  If you have all electric heat for a few buildings with electric hot water, electric dryer, 2-3 high wattage microwaves, huge media devices, sub zero fridge, etc. you will need the larger system.  Not many households need more than 200 amps ever.  I know people that can spend over $700 a month in electric bills and still have 200 amp service.

[MikeC]

We have 200 amp main service panel for a 3000 sq ft house, feeding a 125 amp sub panel for 900 sq ft garage/business, feeding a 100 amp sub in a 1200 sq ft barn.

Yes, it all adds up to more than 200 amp - inspected & passed.

200 amp is plenty sufficient for us. And the panels with the most slots are a good idea.
YMMV

[MountainDon]

Yes, it all adds up to more than 200 amp - inspected & passed.

Ans in the typical home with just one service panel, adding up the value of all the contained circuits is greater than the panel rating.   That's completely normal.