NEW BODY, OLD FEET
SCHEME DESIGN: RE-USE FOUNDATIONS AND FLOOR, NEW HOUSE SET OVER
After living at this post war bungalow for several years, the owners have concluded that upgrading would offer limited results in terms of spatial improvement and environmental performance. They approached Noel Wright Architects to discuss complete replacement: a new house.
The new house scheme involves demolition of the existing down to ground floor slab level only. The new structure will be built above the existing foundations and ground floors. The scheme embodies several principles leading to this decision:
- ECONOMIC – reduce construction cost by re-utilising a serviceable key element from the existing house, the foundations and ground floor slabs. An initial investigation suggests that the saving might be in the order of 10% of the new house construction cost.
- VAT- new houses may be constructed VAT zero rated, whereas upgrading existing houses attracts VAT at the standard rate, 20%. For a replacement house to qualify for the zero rating, the original building must be demolished to ground level. So the re-utilisation of the foundations and ground floors still qualifies the replacement house for the VAT zero rating.
- ECO- SUSTAINABILITY- Avoid the heavy embodied carbon / CO2 aspect of new concrete floors and foundations- this aspect already exists and can be re-utilised without waste. Now that buildings can be much more energy efficient in their use/ lifetime- previously seen as the key environmental impact, the embodied carbon involved in the construction of buildings has gained increased significance in the environmental equation. Structural elements, particularly concrete/ cement and steel, are usually the most carbon intensive in their manufacture.
- THE GARDEN AND EVERYTHING AROUND THE HOUSE- is a good aspect of the existing. This, and things like utilities and drainage, are also very beneficial and economic aspects to re-utilise with a minimum of alteration. This is considerably aided by the re-use of the existing house footprint.
- SOUTH DOWNS NATIONAL PARK PLANNING POLICY – sets restrictive criteria that must be satisfied to gain permission. In this case the key criteria are perceived to be (a) adherence to the limitations on added dwelling size (b) the visual impact of the development within its overall landscape setting (this house is in a rural/ countryside location). We created a notional scheme utilising Permitted Development allowances, although these are also restrictive in the National Park. As a result we were able to justify a final design with a first floor nearing the size of the ground floor plan. The big roof form is a result which satisfies this floor area restriction and retains a relatively discreet presence in the wider landscape.