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Rear Single-Storey
The most popular choice. Extends kitchen or living area into the back garden. Typically 3–5m depth.
📋 Under 40m² — often exempt from planning
⬛
Two-Storey Rear
Doubles the floor area. Adds a bedroom above a ground-floor kitchen or living extension.
📋 Almost always requires planning permission
▭
Side Return Infill
Fills the narrow alleyway beside Victorian and Edwardian terraces. Transforms dark kitchens.
📋 Often permitted development if under height limits
⬚
Wrap-Around
Side + rear combined. Maximum space gain. Ideal for detached and large semi-detached homes.
📋 Likely requires planning permission
⌂
Attic Dormer
Converts unused attic space into a full habitable room or master bedroom. Adds natural light.
📋 Usually requires planning permission