Appendix A: Key terms

  1. The following are key terms used in this document:

    The following are key terms used in this document:

    Note: Terms shown with * are defined in legislation, either in the Building Act 1984 or the Building Regulations 2010, where the definition may be fuller than the definition given here.

    Accessible threshold

    A threshold that is level or, if raised, has a total height of not more than 15mm, a minimum number of upstands and slopes and with any upstands higher than 5mm chamfered. Other acceptable solutions are described in Accessible thresholds in new housing – Guidance for house builders and developers, The Stationery Office Ltd. ISBN 0 11 702333 3. 1999.

    Approach route

    Internal or external path or corridor usually leading to the principal private entrance of a dwelling from a defined starting point (typically the pavement immediately outside of the curtilage or plot boundary).

    Bedspace

    A suitable sleeping area for one person. (A single bedroom provides one bedspace and a double or twin bedroom provides two bedspaces where
    these rooms also meet any other requirements for the relevant category of dwelling).

    Clear access route

    Clear, unobstructed ‘pathway’ to access a window or other feature. Localised obstructions are not permitted unless specifically stated.

    Clear access zone

    Clear, unobstructed space for access or manoeuvring. Localised obstructions are not permitted unless specifically stated.

    Clear opening width

    Clear distance measured between the inside face of the doorframe (or door stop) and the face of the door when open at 90 degrees. Door furniture and ironmongery may be disregarded when measuring the clear opening width.

    Clear turning circle

    Clear floor space, represented by a circle, or an ellipse, that allows a wheelchair user to turn independently in a single movement. A door swing is permitted within a clear turning space unless stated otherwise.

    Clear width

    Clear distance measured between walls or other fixed obstructions (except permitted localised obstructions) or across a path. Skirtings totalling up to 50mm total thickness and shallow projecting ducts or casings above 1800mm may be discounted when measuring clear width.

    Communal or common (area, facilities or entrances)

    Shared area accessed by, or intended for the use of, more than one dwelling.

    Dwelling*

    A house or flat. Student accommodation is treated as hotel/motel accommodation.

    Entrance storey
    The floor level (of the dwelling) on which the principal private entrance is located.

    Flat*

    Separate and self-contained premises constructed or adapted for residential purposes and forming part of a building from which it is divided horizontally.

    Following edge (of door)

    The surface of a door which follows into (or faces away from) the room or space into which the door is being opened – sometimes referred to as ‘the push side’.

    Gently sloping

    Gradient between 1:60 and 1:20

    Habitable room

    A room used, or intended to be used, for dwelling purposes, including a kitchen but not a bathroom or utility room.

    Installed level access shower

    Step-free area with no lips or upstands, suitable for showering, with a floor laid to shallow falls towards a floor gulley connected to the drainage system.

    Leading edge (of door)

    The surface of a door which leads into (or faces) the room or space into which the door is being opened – sometimes referred to as ‘the pull side’.

    Level

    Gradient not exceeding 1:60

    Liftway

    Vertical route linking all floors of a dwelling accommodating (or capable of accommodating) a lift or lifting platform.

    Localised obstruction

    Short, fixed element, such as a bollard lighting column or radiator, not more than 150mm deep that may intrude into a path, route, or corridor, that does not unduly restrict the passage of a wheelchair user.

    Manoeuvring space

    Clear floor space, represented by a rectangle which allows a wheelchair user to turn independently in a series of manoeuvres. A door swing is permitted within a clear manoeuvring space unless stated otherwise

    Pitch Line

    A line that connects the nosing of the treads of a stair.

    Plot gradient

    The gradient measured between the entrance storey finished floor level of the dwelling and the point of access.

    Point of access

    The point at which a person visiting a dwelling would normally get out of a car before approaching the dwelling. The point of access may be within or outside the plot.

    Potential level access shower

    Space capable of providing a level access shower without the need to move walls, remove screed or other solid flooring. It should include a capped- off floor gulley, set at an appropriate level and connected to the drainage system. (Usually provided within a wet room).

    Principal communal entrance

    The communal entrance (to the core of the building containing the dwelling) which a visitor not familiar with the building would normally expect to approach (usually the common entrance to the core of a block of flats).
    Principal private entrance

    The entrance to the individual dwelling that a visitor not familiar with the dwelling would normally approach (usually the ‘front door’ to a house or ground floor flat).

    Principal storey

    The floor level (of the dwelling) on which the main living space is located, where this is not the entrance storey.

    Private (area, facilities or entrances)

    Area belonging to an individual dwelling.

    Ramped

    Gradient between 1:20 and 1:12

    Standard parking bay

    A parking bay 2.4m wide x 4.8m long

    Steeply sloping plot

    A plot where the gradient exceeds 1:15.

    Step-free

    Route without steps but that may include a ramp or a lift suitable for a wheelchair user.

    Suitable ground surface

    External ground surface that is firm, even, smooth enough to be wheeled over, is not covered with loose laid materials such as gravel and shingle, and has a maximum crossfall of 1:40.

    Suitable tread nosings
    Nosings that conform with one of the options shown in Diagram 1.2 of Approved Document K.

    Wheelchair accessible

    Category 3 dwelling constructed to be suitable for immediate occupation by a wheelchair user where the planning authority specifies that optional requirement M4(3)(2)(b) applies.

    Wheelchair adaptable

    Category 3 dwelling constructed with the potential to be adapted for occupation by a wheelchair user where optional requirement M4(3)(2)(a) applies.

    Wet room

    WC or bathroom compartment with tanking and drainage laid to fall to a connected gulley capable of draining the floor area when used as a shower.