Steep staircases in older homes can be a bit of a nightmare to use, feeling like a mountain climbing expedition on the way up and a balancing act on the way down! If you’re adding a staircase to a new or existing space, it makes sense to ensure that it is safe and simple to get up and down. At the same time, you don’t want the angle to be too gradual causing it to take up an unnecessary amount of floor space.
Here at British Spirals & Castings, we will help you to fully understand the options for your space and to find the best type, style and angle of staircase for you. If you’re just trying to get an idea of the options, however, then a good place to start is the Building Regulations and Standards here in the UK.
What is the best angle for a staircase according to the Building Regulations?
The regulations for UK stairs are covered by Approved Document K in England and Wales and Technical Handbook 4 – Safety in Scotland. They don’t simply set a recommended angle for the staircase but also lengths for the ‘Going’ and ‘Rise’ shown in the diagram below:
How steep should a straight staircase be?
A building regulations requirement is that the going and rise lengths should be the same along the full flight of straight stairs. The exact requirements for the angle (pitch), rise and going are slightly different depending on where the staircase is being installed and there are parameters within which we need to work.
Straight staircase for a home
If you’re adding a staircase to a home, then this is classed as a ‘private stair’ and the requirements are shown below:
| Region | Min. rise (mm) | Max. rise (mm) | Min. going (mm) | Max. going (mm) | Max. Pitch |
| England & Wales | 150 | 220 | 220 | 300 | 42º |
| Scotland | 100 | 220 | 225 | – | 42º |
To ensure the overall step size is comfortable it is also recommended that the total measurement of twice the rise plus the going (2R + G) should be between 550 mm and 700 mm. To show how this might work on a staircase we’ve included an example of a straight staircases below:
Straight Staircase for other buildings
If you’re dealing with straight staircases in any other building, including access staircases to multiple flats, then the requirements are slightly different:
| Region | Staircase Type | Min. rise (mm) | Max. rise (mm) | Min. going (mm) | Max. going (mm) | Max. Pitch |
| England & Wales | Utility | 150 | 190 | 250 | 400 | – |
| General Access | 150 | 170 | 250 | 400 | – |
| Scotland | General Access | 100 | 170 | 250 | – | 34º |
Note: If you’re fitting a staircase in an existing building then you may be able to get a little wiggle room but this will be at the discretion of building control so get in touch.
Again, it is recommended that the total measurement of twice the rise plus the going (2R + G) should be between 550 mm and 700 mm. The staircase shown above would meet all of these requirements.
How steep should winder stairs & curved staircases be?
If you’re going for a staircase with a tapered tread then in addition to the requirements for a straight staircase, there are also a couple of other things to take into account.
For winder and combination staircases, the minimum width at the narrow end of the tread must be at least 50 mm. The going of the treads (measured at their centre) must also be no less than those of the straight treads and should be identical for all tapered treads as shown in the example below:
For stairs with treads one metre or wider, the going is measured 270 mm in from the tread edge on either side. These must meet the requirements for straight staircases and be the same distance all the way up.
How steep should spiral stairs and helical staircases be?
Finally, for spiral and helical staircases, there are separate requirements within BS 5395-2. There is no minimum or maximum angle for these staircases but there are clear limits for the going and rise.
The going of spiral staircase is measured in the centre of the tread and at either side 270mm from the tread edge (see below)
The requirements for the going and rise are then dependent on the location of the staircase, and what it is used for as shown below:
| Stair category | Rise (mm) | Min inner going (mm) | Min centre going (mm) | Max outer going (mm) |
| Small private spiral staircase — used by a limited number of people e.g. a staircase in a home which doesn’t go to a communal room like a kitchen or an access stair to a small room not used by the public for a commercial property. | 170 – 220 | 120 | 145 | 350 |
| Private spiral staircase — a main staircase within a home. | 170 – 220 | 120 | 190 | 350 |
| Small semi-public* spiral staircase — used by a limited number of people such as a communal staircase leading to more than one flat. | 170 – 220 | 150 | 230 | 350 |
| Semi-public* spiral staircase — used by a larger number of people such as a stair serving a large area in a factory, office or shop. | 150 – 190 | 150 | 250 | 450 |
| Public spiral staircase — intended to be used by large numbers of people at the same time (meaning room is needed for passing). | 150 – 190 | 150 | 250 | 450 |
For all these staircases, the total measurement of twice the rise plus the going (2R + G) should be between 480 and 800 mm.
Finding the right fit for you
Whatever you project is, we can help you to find the perfect staircase for you. To help get an idea of the design you’d like, take a look at the pictures in our gallery then send us a quote request! We look forward to hearing from you soon.
