We have gained planning permission for the rooftop extension of a Victorian warehouse building on Ellsworth Street, just off Bethnal Green Road. The design company which has occupied the building for the past 25 years has outgrown it but has a strong attachment to the building and the neighbourhood. Our proposal adds two stories of column-free studio space on top of the existing brick structure. A brick skin, perforated in some places to give private terraces, wraps around a hybrid structure of steel and cross-laminated timber. Each floor offers a meeting room and planted outside space.