John T

Hi, I have built a 1.5M high containment wall composed of 6inch blocks laid on sides, cemented half bond, sloping in at 1/4 bubble, top course 6ins on edge, internal pillars every 2M and externally buttressed on old concrete link fence posts. The ground is garden soil down to 1.25m then clay and shale following an old dry watercourse. Backfill is a mixture of foundation shale & clay/soil mix topped off with 1/2m soil. There is gravel drainage along the bottom inside of the wall exiting at one end. The soil area is bounded by pathway approximately 2.5M parallel with the wall and surface water drainage piped clear of the area. I would like to construct 5ft high fencing where SW strong winds blow face on at the retaining wall and fairly sheltered from the soil side Questions. 1 How long should I allow the soil to settle and firm up before posts are erected? 2 How near to the top of the retaining wall should the posts be set, I would prefer 1 ft, vis a vis the constructed weightiness of the wall? 3 How deep should the posts penetrate below ground to cope with high gusts? 4 Would concreting the posts allow for shorter ground penetration? 5 Is there a system for concreting in posts that allow easy removal/replacement with good drainage of post ends to reduce rot? 6 Are there any modern posts that have long life, UV proof and are well regarded in the fencing industry? Still getting to grips with DIY at 74. Regards John