steamup wrote:Define the age of the house. If you have blown in insulation, was it a retrofit? I am betting it was and that would indicated you have an older home. The problem is Blown in settles and isn't perfect for coverage.
An older house is also a good candidate for weather sealing. For a few dollars in caulk, weatherstripping and canned spray foam, you can seal things up enough to make a huge difference. I have lived for 20 years in the house I am in now and still find opportunity to insulate and leak stop.
You said small footprint but didn't define square footage that you live in. 78k btuh output sizing would not be out of line for an older 1500 square foot house.
The house is 83 years old, and is ~1400ft2. The insulation was blown in and I have no idea when.
In my calculation, I didn't factor in the basement. I'm somewhat confident that my infiltration numbers are not terribly bad, as the snow does not melt ever on the north side of the roof during cold days. So it does not appear that I'm losing a lot of heat out the attic. And in reviewing infiltration problems, most folks concentrated on large footprint gaps, not the small ones found around the windows and doors.
However, I have a serious discrepency between my calculated numbers and my real world usage (I know, I'm saving money, but this has become an obsession) so I'm looking for the area of the house that contributing the most to the heat loss. And my guess, based on the replies here, would be the basement.
If I put fiberglass bats in the floor joists, and my loss is not due to infiltration but to heat transfer from top to bottom, that should decrease that factor by quite a bit, no? Or would it be best to insulate the walls?