Hi,

We are in the process of building an addition to our home (originally built in 2000).  The current house is 2000sqft with an 800 sqft basement.  The house has 2x6 stud wall (16" O.C.) with blown cellulose.  The addition will be 760sqft with 325sqft basement.  Also built with 2x6 studs and 16'" OC.  The framing is complete.  We were planning on using blown cellulose for the addition as well, but I just got a quote for spray foam.  It looks like the spray foam in the addition only will cost $1000-$1500 (open cell cheaper, closed cell more expensive) more than the cellulose.  The existing house is pretty tight, but I doubt it would be as tight as the addition if we use foam.
We live in central Virginia.  WInters are moderate, summer is hot.

My question is it worth it to spend >$1000 on spray foam?  The rest of the house won't have it.  Will we ever make up the cost differential with energy savings considering blown cellulose is pretty good insulation anyway?

BM