Hello all. New and my first question. We have a large hedge I share with my neighbour, while the hedge is not a problem for me, it is for my neighbour. We have agreed (jointly) to take the hedge out and replaced with a wall. From all I read, 2 meters is a heigh as I can go, but the hedge is 12 foot and a good sound barrier for both of us. While we don't want a 12' wall, 8 foot would be better we both agree. What can we do please?