2nd Floor Heat Pump Help – Bedrooms/Insulation
We are renovating our 2-floor colonial in Easter MA (Zone 5). Upstairs is 700ish sq ft. We’ll be adding a 2nd floor master bathroom over a family room addition on the 1st floor.
As part of this we’d like to move to heat pumps for both heat and a/c. No existing ducts. We currently run FWH baseboard by oil, and window A/Cs. Temperature is very uneven upstairs in both winter and summer.
Walkup attic that is insulated on the floor/ceiling plane with cellulose. The 2nd floor has a mostly flat/horizontal ceiling but is sloped to follow the rafters for ~2.5 ft at the eaves. Rafters are 2×8. So the 2nd floor ceiling is sort of cathedral-ish at the eaves.
2 Kids rooms are about 12×12 – not huge. Full bath in the hall.
Every HVAC installer says something different.
Some suggest a minisplit head in each room upstairs. Feels like a lot – overwhelming the small rooms and an awful lot of systems to buy/maintain. Unclear to me how the main bathroom gets heat in this scenario. We couldn’t likely get radiant panels in the bathroom.
Some say a ducted minisplit upstairs but remove all insulation and foam the underside of the roof. I believe to do that and hit code in the sloped part means closed cell. The sloped/cathedral portion of the ceiling seems impossible to foam without removing the drywall on the sloped portion in all the bedrooms. That level of gutting the house is not what we planned/budgeted for.
My personal preference – HVAC aside – would be not to foam the underside of the roof and figure something else out.
Is there an alternative I’m missing? Is one (or both) of these approaches obviously wrong?
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Replies
Ducted mini split is the way to go here. You can bury the insulated ducts in insulation. Or, potentially you could squeeze ducts in closets if they align right.
Ductless in every bedroom should be your last resort - I’d add electric baseboard/keep the forced water baseboard and keep the window units over putting in ductless in every bedroom.
Thanks, Paul. The closets are not in great places to deal with the duct work. What are your thoughts on putting the air handler in the attic too? That seems much harder to insulate. We have linen closet in the middle of the 2nd floor we'd be willing to give up (part of) to an air handler but I'm not sure if the noise would be overwhelming.