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Heating and cooling

myadanny | Posted in General Questions on

Building new home with slab on grade 2 storey, R20 slab, R40 Walls, R80 ceilings, triple pane windows (lots of them) . We had an HVAC quote for in floor in slab with a high efficiency furnace to heat second floor then to be used for air conditioning throughout. First floor 2200 sq ft second floor 1100 sq ft (cathedral ceiling on first) .  Thoughts?

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  1. GBA Editor
    Martin Holladay | | #1

    What does "in floor in slab" mean? I'm guessing it means, "tubing installed in the slab for a hydronic system that includes a boiler."

    If my guess is correct, your contractor's proposal is unnecessarily complicated. I'm not in favor of a boiler with a hydronic system for one floor, and a furnace with forced-air ductwork for the other floor. After all, you'll probably need ducts and registers for summer cooling on both floors -- so why not eliminate the boiler and in-floor tubing?

    1. this_page_left_blank | | #2

      Agreed, needlessly complicated. Sounds there'd actually be three systems here, with a separate a/c from the furnace. A ducted air source heat pump replaces all three.

    2. myadanny | | #3


      Problem is this is our third and last home and other two had in floor heat which we loved especially now with ceramic and hardwood floors. Our master bedroom is on the main level and spare rooms upstairs (kids are gone). We had ductless mini-splits in our last house , not real happy with a/c performance very localized to where heads were located.

      We are located in Orillia,Ontario zone 6, would a ducted air source heat pump work there?

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