PPS 6 Addendum Areas of Townscape Character·Page 13·7.6
General Criteria for Development in Conservation Areas
Development proposals in conservation areas must be assessed on their overall massing, scale, proportions, and relationship to context, ensuring harmony with neighbours and local architectural styles. The use of historically dominant materials and respect for the grain of the area, including historic layout and street patterns, are important considerations.
General issues to be taken into account in assessing development proposals in a conservation area include the appropriateness of the overall massing of the development, its scale (the expression of size indicated by the windows, doors, floor heights, and other identifiable units), its proportions and its relationship with its context i.e. whether it sits comfortably. Development should be in harmony with, or complementary to, its neighbours having regard to the adjoining architectural styles. The use of materials generally matching those which are historically dominant in the area is important, as is the need for the development not to have a visually disruptive impact on the existing townscape. It should also, as far as possible, fit into the "grain" of the conservation area, for example, by respecting historic layout, street patterns or existing land form. It is also important where new uses are proposed that these respect the unique character and general ambience of a conservation area, for example certain developments may adversely affect the character of a conservation area through noise, nuisance and general disturbance.
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