Replacing an HVAC Vent in an ICF Build
I am in climate zone 5 (chicagoland). ACH50 hasn’t been run but is expected to be low (less that 1.5, probably lower). House will have an ERV for ventilation and is an walkout basement.
I’ve run a manual-j via cool-calc and get ~20k btu heating and 32k cooling (I imagine the extra cooling is because of south facing windows), with an SHR of 0.863 (I think this is used to get the desired sizing?).
I originally planned to use two fujitsu ARU18RGLX / AOU18RGLX units for their turn down ratio, one for the basement, and one for the main level. They would be using a doing ducts to each room. I’ve included a table for some statistics.
My question is if I need to do ducts to each room or can use a single wall/ceiling unit per floor or go with some ducting. I’ve heard that well sealed ICF has low temperate variance across a house (at distance from the HVAC exhaust) but would love to hear from someone with more experience.
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