Belfast·SPG004 Residential Extensions and Alterations·Page 43·4.3.27
Angles Test for Overshadowing
The angles test is a tool to assess whether a proposed extension causes unacceptable overshadowing of neighbouring properties by checking if it breaches horizontal and vertical angle lines.
Check whether the proposed extension breaches the lines set by the horizontal and vertical angles tests. If it does, the extension is likely to cause overshadowing of the neighbouring property/ properties and permission may be refused.
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