Our Timber sleeper wall is perfect for a more cost effect method of retaining. Although a natural product, we use moisture barrier and effective drainage to make sure that our workmanship gives our timber retaining walls the longest possible life. At our standard, we use 4mm gauge Steel H beam posts at 100/150UC and Bore a 300/450/600mm diameter hole at usually a 1:1 ratio + 100/200mm of extra depth.