Belfast·SPG004 Residential Extensions and Alterations·Page 16·4.1.5
Relaxation of minimum set down and set back requirements
The standard 500mm set down and set back requirement may be relaxed only where it can be proven infeasible due to technical or site constraints, and only if the extension does not project above the ridge line or forward of the building line, and causes no significant negative impact on character and appearance.
The requirement for a minimum 500mm set down and set back will only be relaxed if it can be conclusively demonstrated that it is not feasible due to technical and/or site constraints, and only in instances where:
i. The extension will not project above the existing ridge line and/or forward of the building line; and
ii. Where there will not be a significant negative impact on the character and appearance of the existing property and the surrounding area.
Source — /Users/richardhill/Documents/planning-arch-project/data/documents/belfast/SPG004 Residential Extensions and Alterations.pdf