I have received a few private messages recently asking about soft shell fabrics. Since I feel that this information is probably of general interest I am responding in a forum post.
Softshell fabrics can be best categorized by their porosity in cubic feet per minute (CFM):
Polartec Windbloc 0 CFM… PU layer
Gore Windstopper <2 CFM Porous Teflon membrane without the Gore PU layer
eVENT <2 CFM Porous Teflon Membrane (hard shell product for ref only)
Driclime windshirt 3 – 5 CFM
Patagonia Houdini windshirt 5 CFM
Average human can detect forced convection (wind) above 5 CFM
Polartec Powershield 8 – 16 CFM Perforated Membrane
Polartec Windpro 60 CFM
200 wt Fleece 200 CFM


