It's a construction poly 10ml thick.I no longer use these as you can get 4 or 5 years from ,then they start to crumble.I use metal roofing on all pens now.In the long run they are much cheaper as they can last 30 years.Plus they keep the pens dry.Nice stuff.
Is this just a tarp roof....or is there something more substantial under the tarp?
In N.H.,Tony.