Belfast·SPG004 Residential Extensions and Alterations·Page 15·4.1.3
Ridge line restriction
Extensions must not project above the ridge line of the existing dwelling, which is especially important where uniform building height forms part of the street scene character.
It will not be appropriate to allow for an extension to project above the ridge line of the existing dwelling. This will be especially important where a uniform building height is part of the street scene. The appropriate distance that an extension should be set back and set down will be decided on a case by case basis.
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