Usually not, as long as the room meets the permitted development rules. It must be single storey and must not sit in front of the house. Within 2 m of a boundary it can be no taller than 2.5 m. Further away, the limit is 4 m with a dual-pitched roof or 3 m with any other roof, with eaves no higher than 2.5 m. Raised platforms over 0.3 m are not allowed. Outbuildings and extensions together must cover no more than half the land around the original house, and the room must be used for something like an office, studio or gym rather than as a bedroom. Our planning permission guide explains each rule.
Conservation areas, listed homes and flats
Many of the city's most attractive streets, including Roker Park and Ashbrooke, are in conservation areas. There, you cannot build an outbuilding between the side of the house and the boundary without permission, so a spot at the rear is usually best. Listed homes and flats have no permitted development rights for outbuildings, so they always need an application.
Getting certainty and costs
If your design is close to a limit, a Lawful Development Certificate from Sunderland City Council confirms it is lawful. The householder application fee in England was set at £528 from April 2025 and is now index-linked, so check the Planning Portal fee calculator for the current figure.
Building Regulations
Rooms under 15 m² with no sleeping accommodation are generally exempt. From 15 to 30 m², they are generally exempt if at least 1 m from every boundary or built mainly from non-combustible materials. New electrical circuits must meet Part P. We will tell you where your design sits, and we recommend confirming the details with the council.
