The 100mm rule legislation is often a question we get asked about when working on a commercial or residential staircase project.
As mentioned in our article on Part K regulations, the 100mm rule stipulates that a 100mm sphere should not be able to fit through the gaps in a staircase at any point. This applies to any acceptable forms of guarding to prevent people from falling, such as risers, upright bars, and glass panelling. The rule applies to commercial or residential buildings that are likely to be used by children under the age of five years.
Regulation K2 of the Part K document details the various situations where a guarding system should be provided to areas where people have access in both internal and externally located applications. This includes any stairs, ramps, floors and balconies and any roof tops to which people may have access where it is necessary to protect them from the risk of falling.
Although developers and architects tend to favour horizontal steel stretched wires, the Part K document is very specific in commenting that horizontal rails for guarding should be avoided and any construction should be such that a 100mm sphere cannot pass through any opening in the guarding.
Architects and developers may consider that if the wiring is stretched sufficiently taught it will prevent a child’s head from passing between the wires (100mm sphere rule), and by offsetting the top balustrade rail inwardly a child will not be able to reach the top. However, these design still may not meet Part K regulations.
The below diagram demonstrates the various infill options you could choose to incorporate as part of your staircase project that complies with the 100mm rule.
Whether or not a staircase project is being designed for a commercial or residential property it is important to ensure any structural additions to the property will meet all the current regulation for safety, including the 100mm rule, as this will avoid having to make costly changes later in the project in order to meet building regulations.
If you have any concerns as to whether your projects designs will meet regulations, our advice is to consult an expert like Essential Projects who will be able to provide guidance very early on in your design process and avoid costly re-planning exercises.
For more information, feel free to contact us on 0115 975 5787 or email us at firstname.lastname@example.org