Chapter 6 Development Control

Architectural Heritage Protection Guidelines for Planning AuthoritiesCHAPTER 6 DEVELOPMENT CONTROL6.8.2 If planning permission is to be granted for anextension, the new work should involve the smallestpossible loss of historic fabric and ensure thatimportant features are not obscured, damaged ordestroyed. In general, principal elevations of aprotected structure (not necessarily just the façade)should not be adversely affected by new extensions.The design of symmetrical buildings or elevationsshould not be compromised by additions thatwould disrupt the symmetry or be detrimental tothe design of the protected structure.6.8.3 Generally, attempts should not be made to disguisenew additions or extensions and make them appearto belong to the historic fabric. The architecturalstyle of additions does not necessarily need toimitate historical styles or replicate the detailing ofthe original building in order to be consideredacceptable. However, this should not be seen as alicence for unsympathetic or inappropriate work.Careful consideration of the palette of materials withwhich the works are to be executed can mediatebetween a modern design idiom and the historicfabric of the structure. Extensions shouldcomplement the original structure in terms of scale,materials and detailed design while reflecting thevalues of the present time.6.8.4 In general, modern extensions to a protectedstructure do not have protected status themselvesunless they contribute to the character of thestructure. Therefore works to such an extensionwhich do not affect the character of the protectedstructure itself, for example to the interior of theextension, would come within the normal rulesrelating to exemptions. However, new openingsproposed from the principal structure into theextension would affect it. Care should be takenwhere works are proposed to extensions to ensurethat they do not have an adverse effect on thecharacter of the structure or its curtilage.Well-considered extensions can be successfullyintegrated with a protected structure whetherdesigned in a modern contrasting style (top) orin a matching historicist style (bottom)6.8.5 In urban areas, careful consideration needs to begiven to proposals for the construction of rearextensions to protected structures and buildingswithin ACAs. Rear elevations sometimes containfabric that is useful in reading the history of thestructure, for example surviving older windows ordoors. The effect of extensions may haveconsiderable impact on the appearance of buildingsor on the setting of neighbouring buildings, orindeed on the appearance of the structure whenviewed from a distance (or a set of similar structuressuch as in a terrace), and this should be consideredby the planning authority when assessingapplications.6.8.6 The planning authority should discourage theinfilling of gardens, lanes or courtyards ofarchitectural or historical interest. Open spaces suchas these have a function in the natural illuminationand ventilation of a densely developed urban area.Where surviving plot-divisions remain in the olderareas of towns, these can be of historic interest asindicators of the original layout of the area, forexample the original burgage plots or defensivewalls of mediaeval settlements (or line of the wall).They may even contain historic fabric and thesestructures and their precise alignment should berespected by any new development.The size of new extensions should be in keeping with thescale of the protected structure92