Stair+regulations

Stairs for residential use must comply with the following: Note: 125mm is the estimated minimum size of a young child’s head, which if able to pass through the gap would allow the child’s body to follow. Other **critical dimensions** are shown on the following diagram: ‘Winders’, are normal treads with a tapered length. They have a constant rise to match the other parallel steps and should have a tread going to match other parallel treads, **when measured at the centre of the flight width for flights less than 1.0m wide.** There are is a maximum of only three (3). The accepted formula, **as per BCA**, for calculating riser and tread dimensions for stairs, is **twice** the **rise** + **one** going, or (2R +G). The result of this calculation must fall between 550mm and 700mm. The calcualtions can be effected by te design and layout of the stairs. It sis much easier to make the calculations if the overall going of the flight is **unrestricted** by doorways, walls and other impediments. But in many cases the run of the flight is **restricted,** meaning the stairs will have to change direction, meaning landings or winders may have to be incorporated into the design.Tthis can make some ofthe calculations a little tricky. Your trainer will explain.
 * __BCA COMPLIANCE REQUIREMENTS__**
 * Maximum Risers:** The minimum number of risers required to make a flight is two (2) and the Maximum number of risers allowed without a break/landing/floor is eighteen (18).
 * Risers and Goings:** All risers and goings must be equal throughout the flight or connected flights.
 * Open Risers:** Where open risers are used, the gap between the top of one tread and the bottom of the next tread must not exceed 125mm.
 * Spiral Stairs:** These stairs must not be wider than 1.0m and must have the allowable tread width for the stair at seven tenths (7/10) of the flight width out from the face of the central support pole.
 * Flight Width:** According to the BCA, there is no maximum or minimum width of a flight for residential construction, however it is suggested that the flight be at least equal to the average width of an adult persons shoulders, which is 600mm.
 * Tread Finish:** Treads must have a non-slip finish or have a non-skid strip fixed close to the edge of the nosing.
 * STAIRS WITH WINDERS**
 * Note:** Flights **greater than 1.0m** wide should have the tread going measurement **at 400mm out from the inside handrail side.**
 * Formula for setting out stairs to comply withthe BCA**


 * Check out this Powerpont Presentation for more information in regards to stair regulations**