I can’t speak highly enough about the benefits of insulation. We insulated the heck out of our house when we bought it: floors, attic, exterior walls, interior walls. I had to argue with the insulation guys and insist that yes, I did want every interior wall insulated.
I know that is not what people usually do but it is what I want, and I’m paying the bill, so blow that insulation in!
Sure, savings on electric and gas bills are nice, but the real benefit for me is comfort. It is so luxurious to not have cold feet in the winter and not have hot and cold spots all over, to say nothing of having a quiet house.
We did add AC and it does cost more than sucking it up. Thankfully with the insulation and new roof and passive attic cooling we don’t have to use it all that much to stay comfortable, and the difference is my kiddos sleep at night instead of waking up to screen from overheating. That is lifestyle inflation I never stop appreciating. ;)
How does one spend $400/month on electricity? I don’t even know what that would look like.