aemeijers wrote:

I was talking about foam, not cellulose.

When I was running the numbers a few years ago, dense pack cellulose in the
walls and pro pink blown loose fiberglass in the ceiling ran about 25% more than
what batts would have cost. The cellulose has superior insulation, air
infiltration and noise reduction properties, so that was worth it to me.

Sprayed open cell foam was about 3x the cost of batts. Would have loved to get
it, but couldn't make the numbers work. I did buy Tigerfoam and did the
underfloor in one corner of the house later. The guys who do this for a living
earn their money, believe me. Working with that stuff in a crawl space is not
fun.

There is a newer hybrid approach where you foam the wall cavity first with a
very thin coat, then fill the rest of the space with fiberglass batts. Gives you
the airseal of foam and some R value but reduces the material cost at the
tradeoff of the extra labor to install.