Can we extend our basement?
In most cases the answer is yes but in order to design and cost it we need to find out what lies below your house. This will determine the costs to build it and how straightforward the construction will be. We need to know if there are any watercourses nearby, are there any protected trees whose roots that might affect the design and what are the soil types.
Can we extend our basement without planning permission?
For a house that benefits from permitted development rights the answer is yes it should be possible to build a basement extension without planning approval. However, anything external such as light wells, balustrades will require planning approval.
Can we put a bedroom in a basement?
Basements can contain bedrooms if they have adequate daylight and ventilation, this will be scrutinised during the planning application process. A secondary means of escape may also be required to comply with the building regulations.
How much value does a basement add to my house?
Basements in Richmond, basements in Barnes, basements in Chiswick, basements in Ealing and in general basements in West London typically add between £7,000 and £12,000 per square metre to the value of a house. Basements in Kensington & Chelsea, basements in Mayfair and basements in Westminster the extra value added is more like £18,000 per square metre.
How much does a basement cost to do?
This depends on ground conditions, overall size and the fit out specification. Typically it is between about £4,500 per square meter and £6,000 per square meter.
Will I get planning approval to do a basement?
In London, detailed guidance is explained in the local councils SPD (supplementary planning documents). The majority of councils limit the footprint of the basement to the area under the existing house plus up to 50% of the area under the garden. They are also usually restricted to a single storey in depth.
Creating a feeling of light, airy space should be considered when designing any basement. This can be achieved by the floor to ceiling height, size and shape of rooms created, internal and external glass roof lights, light wells, paint colours, flooring types and lighting. We try to use as large as possible frameless glass sliding doors to create views of gardens and give as much natural light as possible.
A major design consideration is where to locate the staircase(s) from the ground or lower ground floor. The staircase should be a design feature as well as a source of natural light into the basement. Where the staircase lands in the basement will effect how much usable space and circulation through the basement.
On several basement conversions we have located a staircase to connect the open plan kitchen dining space at ground floor and the basement using voids and lots of glass it allows the two spaces to flow and interact with the garden.