These plans represent the Mostyn Estate copies of building control plans for building developments largely, but not exclusively, in Llandudno (since they relate to properties owned by the estate throughout North Wales). They exist only as 8 microfilm copies commissioned by the Estate, which is very fortunate since the originals were destroyed by a fire in the Llandudno Estate Office. The majority of the images on the films have been digitised and printed [omitting repetitions and plans of perceived low interest]. The microfilms are also available for inspection.
The original microfilming appears to have been undertaken without any regard to chronological or geographical order: all 8 films jump about in both date and location with frequent repetitions. However, the entire series is now entered onto the Archive Service's searchable software and can be searched by date, place, personal name or any other term.
This series, however incomplete, is important for the picture it gives of the history of the built environment in Llandudno, as the UDC took the regrettable step of destroying its own (far more complete) series of building control plans in 1974. This series therefore provides a unique picture of Llandudno's development from the 1880s onwards.