Heat pump with limited home insulation — worth it?
We’re debating some major home improvements and are trying to understand whether installing a heat pump makes sense. I’d appreciate any and all advice you can provide!
– 1930s home in the Bay Area, California (climate zone 3C), with very limited insulation in the ceiling and walls. Approximately 1300 sq ft. The roof is mostly flat, with two smaller peaked sections but with no attic space to speak of (i.e., there’s probably about six inches between the interior ceilings and the exterior roof).
– Windows are dual pane, older but in okay condition.
– Home is a little drafty. For example, we need to seal the fireplace.
– We currently have a large floor furnace in the front of the house (no ducts).
After freezing this winter we’ve realized we need to upgrade our heat but want to do it smartly in terms of increased comfort, costs, climate change goals, etc.
Here’s where things get complicated. I understand that in an ideal world, we’d insulate the walls and ceilings first. However, we have some knob and tube electrical wiring, and can’t foresee opening the ceilings and walls to replace the wiring given the costs (and because they won’t help with our heat needs).
We’ve received some mixed feedback from HVAC companies about the feasibility of installing a ducted heat pump. One company said our home was too energy inefficient for a heat pump to work effectively. Another said a heat pump was feasible.
Another wrinkle: we need a new roof soon. One options we’re exploring is whether a foam roof on the flat portion of the roof would provide enough of an insulation “bump” to make a heat pump more feasible. We also want to keep the door open for doing solar down the road (which may mean a foam roof isn’t feasible since it could be harder to add solar to it later).
Lastly, even if a heat pump was feasible, we’re worried about what skyrocketing electricity costs would mean for our monthly expenses (on top of a much more expensive heat pump).
Thanks in advance for your insights!
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