Belfast·SPG003 Residential Design·Page 91·5.2.17
Windows in principal living spaces - sill height requirement
Windows or glazed doors in principal living spaces must have unobscured glass starting no higher than 800mm above floor level to ensure all users can have a reasonable view to the outdoors.
To allow a reasonable view from the principal living space to be experienced by all users, windows or other forms of glazing (for example, glazed doors) should comprise unobscured glass that starts no higher than 800mm above floor level.
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