UPDATE: Permitted Development Rights
From 1st October 2017, permitted development rights will apply to certain light industrial units (Use Class B1(c)), to enable a conversion to residential use (Use Class C3). This provision will only be in place until 1st October 2020. See more details in our useful advice note here.
It is also important to note that the use of 'Class P' PD rights - to convert a B8 (storage and distribution) premises to residential use - must be implemented before 15th April 2018, subject to securing prior approval consent.