One of the most fundamental principles of planning law is that works which constitute development require planning permission. Commonly, securing planning permission requires the submission of an application to the local planning authority. Thankfully, for certain relatively minor or routine forms of development, planning permission is deemed to already exist without the need to apply to the local planning authority: this is known as permitted development.

The Town and Country Planning (General Permitted Development) (England) Order 2015 (the GPDO) specifies the types of development that is permitted development in England. The GPDO also specifies limitations on the extent of what constitutes permitted development and imposes automatic conditions which developers must comply with. Certain types of permitted development also require prior approval from the local planning authority for certain aspects of the works.

One form of permitted development under the GPDO is Class MA: development consisting of a change of use of a building and any land within its curtilage from a use falling within Class E (commercial, business and service) to a use falling within Class C3 (dwellinghouses).

Until very recently, this development would not be defined a permitted development:
• Unless the building had been vacant for a continuous period of at least three months immediately prior to the date of an application for prior approval; and/or
• If the cumulative floor space of the existing building changing use exceeded 1,500 square metres.