dicko wrote:
....
My house, according to the test was leaking at roughly 3 times the
rate of todays standard for a tight home of its size. After sealling
most of what the test found, I was still at twice the current leak
standard. But it would be too costly to replace the bathroom vents
and the can lights, so I decided that was enough. Frankly, I saw no
reduction in either my heating or gas bill last winter so air leaks
must not place a big role in heating problem. Its a 50 yr old ranch
house. What I did notice is that it became more comfortable. Cold
spots were gone.
....

That probably simply means the reduction in heat loss was compensated by
the fuel cost increase such that the total was still roughly equivalent.
What it doesn't account for is what the bill would have been had you
not reduced leakage. And, of course, if you did go from 3X to 2X, you
actually only made a reduction of 1/3-rd which isn't nothing, but it
still left 2/3-rds the existing so it's not too surprising you didn't
cut heating load by a huge amount. It certainly isn't a proper
conclusion to draw that air leakage isn't a significant contributor.

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