CMU Block Home – Fuel Tank Conversion
We own a 1960’s one-story home with a basement that is constructed with CMUs in Wisconsin. Most of the interior walls are blocks and, incredibly to me, the ceiling in the basement is constructed from blocks as well. There’s a fuel tank in the basement that supplies heat for the home to baseboard units on most of the main level. There is one small through-wall AC unit located in the master bedroom. The roof is a 5/12 pitch with flat attic space. Rectangular home with attached garage, approximately 30’x45’ of living space. We are searching for creative ways to eliminate the need for fuel oil and supply both AC and heat to the home. We understand it may not be a conventional solution, but we are open to all ideas and hope to hear from you. Thank you so much for your time!
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Replies
How well insulated is it?
It is a reasonable plan to figure out how you are going to improve the insulation level of the house before specing out heating system so that it is sized appropriately
I do not believe the inside of the blocks are insulated and the attic has not been air sealed yet. Along with the heating system change, we would air seal and insulate the attic with r60 cellulose
The first step would be to figure out your existing heating loads, using fuel consumption, as outlined in this article:
https://www.greenbuildingadvisor.com/article/replacing-a-furnace-or-boiler
Then you need to project how much the heating load will change as you improve the building envelope. I would use an energy modeling program like BeOpt. I'd tweak the model with existing construction to match the observed energy usage, and then see what happens with various improvements.
In terms of equipment to go all-electric, I'd start by figuring out your summer cooling load and seeing how that compares to heating. Unless your heating load is dramatically bigger than your cooling load you probably should just install a heat pump and discontinue the baseboards.