Dont laugh guys but after 3 houses and 20 years proof we grab old carpet or plain underfelt not rubber or synthetic stuff. Its thick enough to stop anything comming up but still allows water to penetrate will break down over years and if weeds start to grow on top they cant get their roots in deep. As I said the 20 years we have done this is proof. Dont use nylon its a bugger to get any weeds out of. For the next house we plan to build on 5 acres in 3 years I already have 5 trailer loads of underfelt ready :eek: Tonto