Chimney Breast removal.

Builder at my property have begun work for removal of chimney breasts. I submitted the application to the council and the inspector visited the site prior to the work commencing. The inspector has now come back after the metal beam was installed and is now asking for drawings and calculation. There was no mention of a structural engineer or drawings when the first inspector came around to view the chimney breasts- Can anyone advise where I can find an engineer for advice on drawings and calculations in the Northolt area?