Hallo, I want to build a 5-foot high pierced screen block wall round my carport area. The end pier of the wall will be close up against my house, with spacing for a capping on the pier. Is it essential to break the concrete against the house in order to cement in a reinforcing rod, and if so, to what depth, bearing in mind there is a drain very close for gutter downpipe and 4-inch soilpipe? Or can I use ties in between the pier blocks and cement the ties into the rendering of the house? Or would I need to go deeper than just the render? Would one or two ties be sufficient? Many thanks for any advice!