R13 vs R15

[Mr T]

I am preparing to insulate a room that is torn down to the 2x4 studs (3.5" depth). (NW Ohio, gas heat, 1/2" fiberboard sheeting on the house.)

Was at Lowes today pricing out insulation. R 13 batts, 108sqr ft for $27ish. R15 batts i think 95ish sqr feet for $43.

Ive never heard of R15 before. same thickness, I guess more dense. Is it worth the extra money. It doesnt seem to be for me. I would need about 2 bags of either for my project.

[suemarkp]

I'd say no. But if you have an energy code than mandates your walls be a certain level, then it may not matter.