Double-storey extensions in London
Extend over two floors to create more living space below and room for bedrooms or a bathroom above.
More room upstairs and downstairs
A double-storey extension can create a larger kitchen or living room below, with bedrooms or a bathroom above. We take on two-storey extension projects across London and look at both floors together, including how they connect to the house you already have.
Think beyond the extra floor area
The new bedrooms need a sensible route from the landing. Downstairs, the original rooms still need daylight and a layout that works. Furniture, stairs, windows and the roof shape all belong on the same set of plans.
Check the existing building
If you are considering building over a single-storey extension, its foundations and structure must be assessed first. We cannot tell whether it will support another floor from its appearance. New structural design, drainage and access will also influence the work.
Permissions and preparation
The planning route depends on the house and the proposed extension. Have the drawings and any restrictions checked before committing to a design. If you also want to renovate the original rooms, include them from the start so the work can be planned together.
Your questions
Is a double-storey extension simply two rear extensions?
No. The two floors share foundations, structure and a roof. They need to be designed together, including how they connect to the existing house.
Can an upper floor be built over our existing extension?
The existing foundations and structure need checking first. You cannot tell from appearance whether an extension can carry another floor.
Do all two-storey extensions have the same planning route?
No. Your house, the proposed size and any local restrictions affect the planning requirements. Have the design checked before deciding which route applies.