Electrical Wiring in the Home/Sub Panel


I am looking to finish my basement.  I will be installing a bar, one bedroom and one bathroom as well as leaving some unfinished space.  The entire area to be finished is about 1200 square feet.  The builder did not wire any part of the basement but the electrical panel is completely full.  All circuits are 20 amp and the service is 200 amp.  I was told that a sub panel for the basement would be the best way to go but would also like a second opinion.  I also found it strange to not see a single 15 amp circuit.  Will I need to upgrade my service past 200 amps to accommodate the additional electrical demands?  If I do decide to go with a sub panel, will I need to remove some circuits from the existing panel and relocate them in the new sub panel to make room for the sub panel supply?  I really appreciate you sharing your knowledge with us.

Hi Mike,

   Based on your description - a sub-panel is clearly in order....but - without knowing all the existing loads...there is no way to know if you'll need to upgrade to a larger service then the 200 amp you already have....typically a 200 amp service is more then sufficient for the average home - unless you have several large loads outside the normal dryer, stove, water heater, etc.

 It isn't unusual to me to see all 20 amp circuits for the 120 volt circuits....we won't run ANY 15 amp #14 wire circuits - other than the smoke alarm circuit - unless specifically requested by the owner - 15 amp circuits are just way too easily overloaded with today's power hungry equipment.I carry a very small amount of 15 amp breakers and #14 copper wire on my service vans....we use mostly #12 copper and 20 amp breakers.

 Yes - if your current 200 amp panel has no open slots.....you will need to remove either 2 single pole breakers(one on top of the other) or one double pole breaker to accommodate the new double pole breaker that feeds and protects the new sub-panel. Based on your new loads...a small 10 or 12 space sub-panel should be all you need - unless you plan on substantial additions in the future.

 Hope this 2nd opinion helps Mike...if you need additional help - please follow-up.
NOTE: As I recover from recent open heart surgery - I am out of the office often with medical appointments, etc...and will be marking myself as "away" at this site until I have made a better recovery(surgery left me anemic...) - However, you can still reach me by direct email at :


Best Wishes,

Bob Osgood
Owner / Master Electrician


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Electrical Wiring in the Home

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Master Bob


Master Electrician / Owner RKO Electric (USA Only) - can answer most of the typical residential, commercial and industrial electrical questions regarding new installations, wiring additions, lighting, switches and receptacle outlets and electrical upgrades of any nature.I will make every effort to respond to your questions as soon as possible at the end of the work day...very busy electrical company - your patience is appreciated. Stop by and see us at: www.rkoelectric.com


Licensed Master Electrician with over 34 years licensed experience - updated with the latest NEC Codes every 3 years since 1978. Over see the daily electrical operations of two electrical companies. Also serve as a judge / editor (for Electrical Contracting Products Magazine) to help select which new products are fit and safe for electricians and the electrical market.

2 Years Technical College - Degree in Electrical Construction & Maintenance (Dean's List) OSHA Safety Certified (10 & 30), CPR / Advanced First Aid Certified

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