Legalities Of Building Staircases

There are a variety of styles of staircases such as spiral, metal, wooden, U and double L and more besides, but there are only three main categories. This article identifies the main categories and the legal requirements surrounding the measurements for their construction.

The local building rules that had been introduced after the Great Fire of London were upgraded into the National Building Regulations in 1965. There have been two major updates in this time. The first one in 1985 the format was simplified and broken down in to separate parts that dealt with specific areas of the building trade such as fire safety, resistance to the passage of sound and the prevention of falling, collision and impact. It is this last section that covers the legalities of staircase design.

The most recent change in legislation came into effect in April 2013. The new requirements regarding the measurements are listed here. All of the measurements given are in millimetres.

Institutional and Assembly Stair

This type is found in buildings where there will be lots of people using them such as hospitals, hotels, nightclubs and schools. The required measurements are as follows:

  • The length of the tread including the overlap of the one below is 280mm. This is also known as the ‘going’.
  • The maximum height of each single one must be 180mm.
  • All new ones must have a minimum width of 120mm.
  • From the top to the bottom of it there must a handrail on both sides of the structure.

Private Staircases

This type is usually found in private residences and are not just for going between the ground level and the first floor, but also commonly used for loft conversions.

  • The minimum going must be 220mm.
  • The maximum height between each one must be 220mm.
  • A gradient rise of no more than 42 degrees.

General Stairs

This category is for all the other different places you can find them, such as office blocks and blocks of flats.

  • A minimum going of 250mm.
  • The maximum height between each one must be 190mm
  • When designing and building this type of structure there are also other legal requirements that must be considered, whichever category your one falls under:
  • From the gradient or rise of staircase there must be at least 2 metres headroom at all points on it.
  • The landings between flights needs to be at least the same width as the shortest step within the case.