Attic Insulation R Values

Submitted By
ghost7071
Answers
1 expert, 0 community
Q:

Putting more insulation over existing roll insulation (2 layers approximately 8" total). For only $2 more I can put down R30 vice R13. Would it be of more advantage to put the R30 since I'm up there putting it in anyway or am I just wasting my money? The current insulation is the 21 year old stuff.