I'm intending to completely renew my driveway which is long enough for three cars in line, but very narrow, so I'm excavating about 1m to the side from a raised front lawn, and will build a small brick retaining wall. The nett addition to the driveway surface means that I will need PP unless I either provide drainage in the form of a soakaway (or similar) or use permeable blocks on a substantial bed of MOT Type 3 or similar.
My problem with the latter is that the driveway slopes towards the road and we have quite heavy clay subsoil. So I would expect that most of the rainwater would immediately flow to the base of the driveway, and spill out onto the road, defeating the object of having permeable blocks.
I wondered whether excavating a soakaway at the base of the driveway itself (adjacent to the footpath) would the the best solution, and use either a drainage channel to catch surface run off from normal blocks, or to lay one pack of permeable blocks at the bottom of the slope, and standard blocks over the remainder. I was thinking something like 600mm x 600mm, the full width of the drive (c2.4m). Does this sound workable?
My problem with the latter is that the driveway slopes towards the road and we have quite heavy clay subsoil. So I would expect that most of the rainwater would immediately flow to the base of the driveway, and spill out onto the road, defeating the object of having permeable blocks.
I wondered whether excavating a soakaway at the base of the driveway itself (adjacent to the footpath) would the the best solution, and use either a drainage channel to catch surface run off from normal blocks, or to lay one pack of permeable blocks at the bottom of the slope, and standard blocks over the remainder. I was thinking something like 600mm x 600mm, the full width of the drive (c2.4m). Does this sound workable?
