UK BUILDING REGULATIONS FOR STAIRCASES

A.  Get the Full UK Building Regulations for Staircases Part K 

A.  The 'Rise' is the measurement from the top surface of a tread to the top surface of the tread above or below. The 'Going' is the measurement from nosing to nosing, and NOT the depth of the tread itself. On a domestic staircase, the minimum permissible rise is 150mm, and the maximum is 220mm. The minimum permissible going is 220mm, and the maximum is 300mm. The normal relationship between the dimensions of the rise and going is: twice the rise plus the going (2R + G) = between 550mm - 700mm. The rise and going on each step must be consistent throughout the flight. Always bear in mind that the maximum pitch angle on a domestic staircase is 42º. 

A.  The first thing to determine is the dimension between the finish floor levels the staircase is serving (Floor to Floor). In this example let's assume a typical floor to floor dimension in a modern UK house is 2600mm. Now divide 2600mm by the number of risers - typically 13, which means each Rise will be 200mm. (200 x 13 = 2600) To find the Going that will give us a 42º pitch with a 200mm Rise, divide the Rise by tangent 42 (R ÷ Tan 42 = G) 200 ÷ tan 42 = 222.12mm Going. If space allows, you could reduce the Rise and / or increase to Going to reduce the pitch angle and make the staircase easier to climb. For example, a 180mm Rise with a 230mm Going will result in a pitch angle of 38º

A.  On the access between levels on a staircase there must be a minimum headroom of 2m. You should take the measurement from the pitch line, or from a finished floor or landing, to the ceiling above, or any obstruction overhead, such as a beam.  The pitch line is a line drawn connecting the front edges of all the nosings - see Staircase terminology explained

A.  For loft staircases, where there is a sloping ceiling and not enough space to achieve a 2m headroom, UK Building Regulations permit you to reduce the headroom to a minimum of 1.8m at the outer edge of the tread, as long as there is a minimum of 1.9m headroom at the midpoint of the tread. You should take the measurement from the ceiling vertically down to the center line on the tread below.  see Approved document K, page 8, section K1

A.  The handrail should be positioned 900mm - 1000mm above the pitch line on the staircase, or above the floor level. If the staircase is used by children under 5 years of age, the balustrading must be constructed in such a way as to ensure that a 100mm sphere cannot pass through any opening anywhere in the balustrading*. It must also be constructed in such a way as to prevent children from readily being able to climb up it. If the stairs are 1000mm or wider you must provide a handrail on both sides.

* This also applies to any gaps between the treads on an open tread staircase.

A.  UK Building Regulations state that: If the stairs are 1000mm or wider, provide a handrail on both sides. Of course, if you or someone in your family are elderly, you may wish to install handrails on both sides of the staircase.

A.   UK Building Regulations state that: Stairs may have open risers if they comply with both of the following:

a) overlap treads by a minimum of 16mm

b) construct the steps so that a 100mm diameter sphere cannot pass through the open risers

A.  In addition to Part K, your should refer to BS 5395-2, which is divided into 5 categories, the first two of which deal with stairs in private dwellings. The remainder are only for stairs in Public places.