Fire Safety
Internal doors may be required to be fire rated if they are on an escape route or form part of the compartmentation of the building. The fire rating will be achieved by an appropriate assembly of the door leaf, frame, intumescents and associated hardware. Some fire door assembles will need to be resistant to the passage of smoke.
Acoustics
A door used as the entrance to a flat will need to provide suitable levels of sound attenuation
Ventilation
Internal doors may be required to contribute to the ventilation of a building possibly by the provision of a suitable gap underneath the door to permit the passage of air. In these circumstances consideration will need to be given to the possible conflict with the maximum threshold gap allowable for a fire door.
Protection from falling
When a door opens near a stair there are restrictions limiting the way a door is permitted to block the flight or landings
Conservation of Energy
If an internal door is fitted between a heated space and an unheated space the heat loss through the door and frame together will be restricted due to specified levels of thermal transmittance (U-value).
Access to and the use of buildings
Internal door assemblies within the entrance or principal storey of a building will be required to open to specified widths to enable full access to the facilities within that storey.
Safety in Use
Any glazed areas in or near to an internal door will need to be fitted with glass which should be in small panes or should be robust, so as not to break, or if it breaks, it should break safely.
