We are in the planning stages of designing a new home to be built to passive house standards, although not interested in certifying it. We are trying to decide between having a basement vs. a slab. The house will be around 3000 ft2 and we do have room to do either option. Soil conditions are not a factor, we are located in Uxbridge, ON. We are on well and septic. My goal is to heat/cool with an ERV and mini split system, not radiant in floor. I have several questions about the merits of each option, and would appreciate advice.
1. Cost - I know a slab is cheaper but having a basement that we can finish allows for a smaller footprint with less walls and roof material. Is there a big difference in cost?
2. Access for mechanical - I can't get my head around having to embed drains, plumbing, electrical, etc in concrete as opposed to putting it under floor. Not to mention running ducting for ERV. Is this a valid concern? What if there is a leak in the drains, how would you ever know?
3. What about a hybrid - we don't need a full basement, what are the implications of having half of the footprint as a slab, and half basement?