[neophyte]

Hi all, I live in Northern Virginia and am about to install a dry laid flagstone patio. I'd planned 4"+ compacted sub-base of bluestone under 1.5" thick natural cleft flagstone.

Is there value in putting landscape fabric on top of the bluestone sub-base and then adding 1" or 2" of stonedust atop the fabric as a base prior to placing the flagstone?

I'm worried about diminishing returns, but do want the finished product to stand up for 20 years and don't want to skimp. is this overkill? thanks very much.