Minimum Space Standards

Permitted Development Conversions

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Permitted Development Conversions


Recent changes to Permitted Development Rights  allow conversions of offices and shops to C3 residentialsubject to gaining ‘prior approval’ from the Local Planning Authority ( e.g. for flood risk, highways/transport and contamination issues).

The accommodation created is subject to minimum space standards. The required minimum floor area (Gross Internal Area or GIA) for a new 1 bedroom, 1 person home (including conversions) is 37 sq metres. 

For a 1 bed, 2 person home the floor area must be 50 sq metres, and all new homes have to provide adequate natural light.


Minimum Standards

a.   Each dwelling must provide at least the gross internal floor area (GIA) and built-in storage area set out in Table 1 below

b.   A dwelling with two or more bedspaces has at least one double (or twin) bedroom

c.   In order to provide one bedspace, a single bedroom has a floor area of at least 7.5m2 and is at least 2.15m wide

d.   In order to provide two bedspaces, a double (or twin bedroom) has a floor area of at least 11.5m2

e.   One double (or twin bedroom) is at least 2.75m wide and every other double (or twin) bedroom is at least 2.55m wide

f.   Any area with a headroom of less than 1.5m is not counted within the Gross Internal Area unless used solely for storage (if the area under the stairs is to be used for storage, assume a general floor area of 1m2 within the Gross Internal Area)

g.   Any other area that is used solely for storage and has a headroom of 900-1500mm (such as under eaves) is counted at 50% of its floor area, and any area lower than 900mm is not counted at all

h.   A built-in wardrobe counts towards the Gross Internal Area and bedroom floor area requirements, but should not reduce the effective width of the room below the minimum widths set out above. The built-in area in excess of 0.72m2 in a double bedroom and 0.36m2 in a single bedroom counts towards the built-in storage requirement

i.   The minimum floor to ceiling height is 2.3m for at least 75% of the Gross Internal Area