Hi guys, again! I recently posted a thread about my BCO wanting me to install cavity wall trays over my lean to roof extension, I did this to keep him happy, but now he's picked up on another issue in the fact that I have placed insulation boards (celotex) between my cavity which is only 50mm without an air gap (i had to build above existing 50mm cavity walls which already had insulation in the cavity. My BCO said that i will get damp through the wall (it will be a pebble dash rendered wall) so I will have to clad the exterior to prevent this. I have been looking at many "pro" builds on youtube since, and have found that many are placing insulation without a gap into the cavity, see attached screen shots. So why is my BCO telling me I can't do this? Also now i'm worried for his next visit, that I built a cavity extension wall " T " from my excisting house wall but have only used wall joining bars and not removed the blocks in between to create a vertical damp break. But again, looking at the pro videos on youtube all they use is wall joiners without creating a damp break, again see pic attached. So before he pics up on that, is it allowed to simply but a cavity wall against an external existing wall without a vertical damp break?