Mod note: Member is in Saskatchewan, Canada.

My in-laws may spend some time with us and I am looking at doing our basement which my wife and I would have a bedroom and rec-room, then her parents would have the upstairs bedroom and living, we would eat upstairs but still have our separate spaces.

Here is what is existing in my 100 amp main panel.
960sf house, 2 bedroom and a craftroom, standard kitchen (electric stove, fridge, dishwasher no garbage disposal) living/dining room and bathroom. Laundry room.

Here is what is going to be in the basement. 2 bedrooms, kitchenette (small fridge for snacks, microwave) rec room, washroom 3000watt of electric baseboard heaters for supplemental heat as ducting from furnace is there.

Laundry closet is being added on main floor so in-laws do not have to go up and down stairs but keeping main laundry in basement as the closet can not have full size appliances, stacked unite needs 2pole 30 amp breaker. Storage-room is approx 140sf off of the 960sf so about 820sf of living area in basement.

The basement would need to be on a sub-panel as there is not enough room left in the 100amp main panel. Wondering what size of breakers I will need feeding the sub-panel and if the 100 amp main can handle it all?

TIA

 

I won't comment on your specific questions. But I will comment that the new living facilities will need it's own exit to meet code. Along with permits from you town or local government.

edit...I just realized that you are non-US. You need to contact your local municipality and find out what is required and what is or is not allowed.

 

You did not say anything about your furnace. Is it a heat pump? Does your house have air conditioning? Are the clothes dryers electric or gas?

I would say the 100 amp main panel is inadequate. I would feel better having 100 amp for each unit.

 

It is only one unit. Just finishing basement.
Furnace and hot water are gas.
Clothes dryers will both be electric.
Oven in kitchen is electric.

 

Mod note: Member is in Saskatchewan, Canada.

I would suspect your 100 amp service will be enough, even with the addition of the electric heat. ( Which I think it a very good idea BTW ) To be sure I would suggest googleing "Load calculation" and doing one. Here is one: Whole House Load Calculator

Your subpanel would likely be fine with a 60 amp feeder.

 

I think my terminology may have confused things. not a kitchenette. More of a snack counter. Counter height fridge and a microwave.
The reason for not just having laundry upstairs and none downstairs is there is not room for full size appliances. So a 24 inch deep stacked unit will fit but still need.full.size for.comforters and such.
Think of this more like when families finish basements for teens.

Did that make it clearer or just muddy things up.

 

Gut feeling is that your 100A service will be adequate. You can do the full calculation, but I would not recommend an upgrade.