ductboard should be outlawed
it is the most horrible thing there is to run air through, next to a fiber glass filled septic tank.
i move to texas from maryland and everyone here uses the SH_T. not because they think its better but because they think its cheaper. really it is because i am in an area where they think $10.00 an hour is good money and to pay someone with experience $15.00 hrly to do something right is just unheard of.
any pinhead with a yard stick, razor knife and a roll of tape can build a visually suffiecent duct system...but not in my house.