As you say, No.1 is complete their building regs application form and pay their fee. They should really ask for design documentation as they would if you were carrying out structural modifications but I doubt if they will.
No.2 is the same as any other building regs application, you ask them at what stages they want to site inspect the works.
That's when the fun will start....
No.2 is the same as any other building regs application, you ask them at what stages they want to site inspect the works.
That's when the fun will start....