I have a customer who is getting natural gas on her street very soon. I see no way to run ductwork in a custom remodeled basement. Mostly hard lid. Low ceiling. If I put the furnace in what is now the mechanical room, she will have a 5-6' ceiling in some of the finished area in order to get the air where it needs to go. That will be pretty ugly. Lots of nice wood paneling that would need a bulkhead. 1960's house.

Anyway, I want to put a heat pump in the attic and a wall mount ductless in the basement. She is concerned over the energy cost of electric over gas. I am not a fan of putting a gas furnace in the attic, except if I went with an 80%.

Anyone know of how I could figure (and prove to her) that a heat pump could be just as efficient as gas.

I plan on using an air to air Bosch heat pump or possibly a ducted mini split for the first floor. This is a one story house.

She has an oil boiler now with baseboard convectors. She thinks it is costing too much and wantsto take advantage of pretty cheap gas.