What kind of peak load could I achieve for my house?
Dana had mentioned on another thread about the peak load sounding high for a house so i’m wondering how much i could do for my house if i could insulate and airseal it better. Hard to do based on my circumstances but for interest sake and something to work towards.
I live near Toronto Ontario, 99% design temp about 0F (-19C) in a house that is about 700sq ft. Poorly insulated about 14.5ACH50. Single story, 2/3 basement, 1/3 crawlspace, balloon framed, no basement floor (concrete) or basement wall insulation (brick) above ground true 2×4 loose fill cellulose walls, conventional attic true 2×8 iirc with old fiberglass paper faced batts between the rafters with the paper mangled up by animals over the decades. 2/3 of the attic is easy to stand up in, 1/3 has enough room to crawl in so i can’t do R50 unless its in contact with the rafters). Much of the air leakage is in the basement crawlspace and the balloon framing allows some gaps that extend from basement to attic and are partially sealed up as well as i can at this point.
Last winter we had a few weeks below the 99% temp and my 40K 95.5 AFUE furnace held up fine but for more then day was almost exactly at the design temp so i did some math based on the furnace run time between first and second stage dividing by efficiency and determined my peak load is about 25K (lets say ±2k). This is with vents closed in a few rooms and doors closed, one being an attached outside storage room.
I have the Hot2000 data for my house and it says the peak load is a bit over 40K so its not very accurate. I can hunt it down and upload it if that will help, let me know.
The basement is unfinished and the head room makes it a bad idea to insulate the floor and being a century plus old house i do not want to insulate the brick basement walls in case the lack of heat could cause them to crack. Perhaps not likely but I’m not wanting to chance it.
I am curious if i could get the air leakage under 5ACH50 and the attic insulated what kind of peak load i could get down to.
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