Dear Suresh
Generally skirting on walls is constructing projecting from the walls. But it is better if flush skirting is constructed flush with the wall plaster because it eliminate the dust collection on the top of wall skirting and also eleminate the spoiling of the portion just above skirting while cleaning the top of skirting. In this process either we have to cut wall or to construct brick wall with back offeset up to one brick height.