Posted: Mon Oct 16, 2006 8:52 pm
Hi
We are replacing a very 'weathered' tarmac surface on a driving/parking area with gravel. We have excavated and levelled the ground, which is largely rock (sandstone). We are then spraying with sodium chlorate and then laying a semi-permeable membrane. On top of that, we are advised that a suitable material for the sub-base is the scrapings from the old yard surface, which are being termed 'finings' (and are certainly much finer than DTp1. My concern is that this material looks quite like soil, in which I fear that weeds will grow up through the gravel. I am also concerned that the fine grade of this sub-grade material will block the pores in the membrane, eventually causing rainwater to gather. Any advice gratefully received. Thank you.
We are replacing a very 'weathered' tarmac surface on a driving/parking area with gravel. We have excavated and levelled the ground, which is largely rock (sandstone). We are then spraying with sodium chlorate and then laying a semi-permeable membrane. On top of that, we are advised that a suitable material for the sub-base is the scrapings from the old yard surface, which are being termed 'finings' (and are certainly much finer than DTp1. My concern is that this material looks quite like soil, in which I fear that weeds will grow up through the gravel. I am also concerned that the fine grade of this sub-grade material will block the pores in the membrane, eventually causing rainwater to gather. Any advice gratefully received. Thank you.
