I hope you are not driving while.....
I would check locally, you need to know exactly what is required. I'll guess: Type X gypsum with a 6mill. barrier on the heated side. Foam will satisfy the B.D. depending on thickness for your Code.
Clothes taking longer to dry?
Clean the dryer screen in HOT water if using fabric softener sheets.
They leave a residue that impedes air-flow, costing you money.
Clean the ducting in the last six months? 17,000 dryer fires annually!