My house is in the middle of construction, and rather than going with a limited-use crawlspace, decided to go with 8ft basement walls.

It has no windows & will house the home's mechanicals, be used for storing seasonal items and has its entrance from the garage, not the house. The construction is ICF and I will be installing drywall.

I'm working with an energy advisor who has past employment working with heating systems. He advised that I do not need to heat the basement but that do I need to insulate the floor above the basement (R 40?) and make sure that the ductwork is also insulated.

The HVAC company that will be installing the central heat pump system is telling me that I need to heat the basement to 15C-ish, that they'll put 2 or 3(?) vents down, and that I don't need to insulate the floor or the ductwork.

The HVAC said that if it was a crawlspace they would not heat it as it's not considered liveable space. However, I don't consider my basement as liveable space either.

I've consulted a 3rd party (Dr Google!) and have only found recommendations from HVAC companies advising to heat the basement.

My energy advisor is saying that it's unneccessary and a waste.

Please, who is right?