We are building a new 5,400 sq. ft. home. We did the calculations for our ungrounded service entrance and learned that we need a 224 amp panel. The next typical service size available from our electric company that is larger than 200 amp is a 400 amp service. Our distance from the meter to the house is 350 feet. We have 1/0 AL run to house already for temporary construction power. What size service do we actually need? And if it is a 400 amp service, do we need to increase our conductor size? Thank you very much for your expertise. Frank Page

Frank, I can only assume an electrician is going to be doing this work. They will have all the knowledge to do this job.

Well, if a load cal was done, and it came in at over 200A then you DO need to go to a 400A service.

Just so you know, yes, you do need to replace the wire, big time.
350 feet is also too far for standard size wire. You will either need the transformer moved closer to the house or upsize the secondary service lateral conductors.


5,400 sq/ft?? Must be nice.
Professional athlete or corporate lawyer?