Type | Riser | Going | ||
---|---|---|---|---|
Min | Max | Min | Max | |
Domestic Property | 150mm | 220mm | 220mm | 300mm |
Utility Staircase | 150mm | 190mm | 250mm | 400mm |
General Access Staircase | 150mm | 170mm | 250mm | 400mm |
On a staircase, as well as taking into account the minimum going and maximum riser, you also need to allow for a maximum pitch line. The pitch line is the angle of the staircase, measured as a straight line from the end of each nosing. For domestic staircases the maximum angle for a staircase is 42 degrees and means that when calculating the riser based on the height you are working to, you need to allow for a going that creates at least the minimum angle. On the table are a list of possible risers with a maximum of 220 and the relative going dimension that will be required in order to form 42 degrees. With most staircases you are trying to fit within a small space and therefore you often work to this table to calculate your staircases dimensions. As well as the minimum rise and going, a staircase also needs to have even risers throughout each flight. This means that when calculating the riser for a staircase, you have to divide up the overall rise equally. For example if you have a an overall rise of 2600mm and 13 risers, then each rise will be 200mm. The going for this staircase based on maximum 42 degree pitch line would be 223mm.
Rise | Minimum Going |
---|---|
198 mm | 220 mm |
199 mm | 220 mm |
200 mm | 223 mm |
201 mm | 224 mm |
202 mm | 225 mm |
203 mm | 226 mm |
204 mm | 227 mm |
205 mm | 228 mm |
206 mm | 229 mm |
207 mm | 230 mm |
208 mm | 232 mm |
209 mm | 233 mm |
210 mm | 234 mm |
211 mm | 235 mm |
212 mm | 236 mm |
213 mm | 237 mm |
214 mm | 238 mm |
215 mm | 239 mm |
216 mm | 240 mm |
217 mm | 242 mm |
218 mm | 243 mm |
219 mm | 244 mm |
220 mm | 245 mm |
For standard stairs England, Northern Ireland, Scotland and Wales. The minimum headroom must be 2m above the pitch line of the staircase, the pitch line being the imaginary line drawn the nosing’s of the stairs with the common misconception being that the 2m size is taken from the top of the treads. For loft conversions there can be special dispensation whereby the headroom necessary is only 1.9m, this allows for the installation of staircases in spaces that wouldn’t usually allow.
One of the most important regulations on a staircase, or on any form of balustrade, is that there cannot be a gap larger than 99mm anywhere on a staircase. The most relevant place that this regulation effects is the balustrade on the staircase, affecting the distance between spindles or balustrade panels. This prevents the possibility of small children potentially falling between any gaps.
The other relevant location for this regulation is on an open plan staircase. On these staircases there are gaps between the treads and these gaps, like the balustrade, cannot be bigger than 99mm. In order to prevent this becoming an issue there are multiple solutions including safety risers in timber or glass, a safety rod which is usually in metal or lastly you can manufacture the treads so that they are thick enough so that the staircase adheres without alteration.