Our renovations fall under permitted development, however our Architect A1 Associates recommended we seek confirmation from the council, which we agreed with, especially as we know how important it is to have all the correct paperwork in place when you sell. This permission cost about £90.
Once this approval was received, our architect submitted building control plans, setting out the materials / positioning of joists and other complex calculations, this costs about £1,000, which includes the visits from the building inspector. It’s beneficial to get to know the building control team, so they can provide guidance during each stage, as an example, RSJ’s will need to be checked before they are covered.