Unusable Area - Unusable Area is the Total Floor Area taken up by
spaces which can not reasonably be used for any purpose or
function.
Unusable areas - Floor areas rendered substantially unusable
include:
• Areas with a net length or width of less than 0.25 m (after RICS)
• Areas with a floor area of less than 0.5 m2 (after NEN)
• Areas with a net height of less than 1.5 m (after NEN and RICS)
The total floor area can be said to be made up of usable floor area and unusable floor area.
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