Planning Use Classes: C3 and C4
In UK planning law, a C3 use class represents a standard family dwelling, while a C4 use class represents a small HMO (3 to 6 unrelated people).
Understanding the UK's Town and Country Planning (Use Classes) Order is fundamental for any investor looking to convert properties. The residential market is dominated by two specific classes: C3 and C4.
Class C3 (Dwellinghouses) covers standard properties used by a single person, a family, or no more than 2 unrelated people living together.
Class C4 (Houses in Multiple Occupation) covers properties shared by 3 to 6 unrelated individuals who share basic amenities like a kitchen or bathroom.
Permitted Development
Nationally, property owners have Permitted Development (PD) rights to change a property from C3 to C4 without requiring a full planning application. However, local councils can block this automatic right by implementing an Article 4 Direction, forcing investors to apply for full planning permission.