These stairs make a 90-degree turn, typically at a landing. This type of staircase can fit into a corner, making it a good choice for space utilization.
L-shaped stairs, also known as quarter-turn stairs, are used in both residential and commercial buildings for a variety of purposes. They are especially popular because they can add architectural interest, provide a level of privacy between floors, and be more compact than a straight staircase.
What are the primary uses?
- Space Management: L-shaped stairs can be more efficient in terms of space usage compared to traditional straight staircases, making them a popular choice in areas where space is a limiting factor. They can be conveniently located in a corner of a room or even around a corner in a hallway.
- Visual Appeal: With their bend, usually at a right angle, these stairs can add an appealing architectural element to a building. They can be designed in many styles and materials to suit the aesthetic of the space.
- Break in Elevation: The landing in an L-shaped staircase can provide a comfortable rest spot, particularly useful in tall buildings.
- Safety: The landing can also break a fall, which makes these stairs a safer option compared to long, straight staircases.
- Privacy: L-shaped stairs provide a visual barrier between floors, offering increased privacy.
- Interior Design Flexibility: The landing area of these stairs provides a space for interior decoration, and can be used to display art, photographs, or plants.
In industrial or commercial settings, L-shaped stairs might be used for similar reasons, such as efficient use of space and enhanced safety. They may also be used in multilevel warehouses, factories, or office buildings to provide access between floors. As always, in such settings, they need to meet the safety standards and guidelines set by regulatory bodies.
L-shaped stairs, also known as quarter-turn stairs, designed to be compliant with both OSHA (Occupational Safety and Health Administration) and IBC (International Building Code) standards incorporate specific safety measures and structural requirements. These are designed to enhance user safety and accessibility.
- Stair Width: The IBC requires that stair width be at least 44 inches for buildings that accommodate more than 50 people and 36 inches for buildings accommodating fewer than 50 people. OSHA requires stair width to be at least 22 inches.
- Treads and Risers: The IBC mandates that riser height must not exceed 7 inches and tread depth must be a minimum of 11 inches. For industrial stairs, OSHA requires that risers be from 6.5 to 10 inches and tread depth be a minimum of 9.5 inches.
- Landings: Both OSHA and IBC require that stairs have landings at appropriate intervals. IBC mandates landings at the top and bottom of the stairs, and every 12 feet of vertical rise. The width and length of landings should be at least as wide as the stairs.
- Handrails: Stairs with four or more risers should have handrails. According to IBC, handrail height should be between 34 and 38 inches, while OSHA requires them to be between 30 and 37 inches, unless the stairs are being used by children.
- Guardrails: Both OSHA and IBC require guardrails on open sides of stairways to prevent falls. IBC requires guardrails to be at least 42 inches high, while OSHA requires them to be between 42 inches and 45 inches.
- Non-slip Surfaces: OSHA requires stair treads to be slip-resistant.
These are the general requirements, and the exact standards can vary depending on the specific use of the stairs, the nature of the work being performed, and local building codes. Therefore, always consult OSHA and IBC standards or a safety professional to ensure full compliance.
The Americans with Disabilities Act (ADA) and the International Building Code (IBC) provide standards to ensure L-shaped stairs (also known as quarter turn stairs) are safe, functional, and accessible. Here are some guidelines for ADA and IBC-compliant L-shaped stairs:
- Width: The IBC requires stairways to be at least 44 inches wide, though this can be reduced to 36 inches in certain residential situations. ADA does not explicitly mention width, but it should be sufficient to allow for the easy passage of individuals, including those using assistive devices.
- Rise and Run: The maximum riser height should be 7.75 inches, and the minimum tread depth should be 10 inches, as per IBC. ADA does not explicitly define riser height and tread depth, but the emphasis is on ensuring stairs are accessible and safe for all individuals.
- Handrails: Both ADA and IBC require handrails on both sides of the stairs. Handrails should be between 34 and 38 inches high, according to both ADA and IBC. They should extend beyond the top and bottom of the stair flight and be returned smoothly to the floor, wall, or post.
- Stair Landings: Landings are required at the top and bottom of the stairs, and where the stairs change direction, in accordance with both ADA and IBC standards. The landing should be at least as wide as the stairway and at least 60 inches long in the direction of travel, according to ADA. The IBC requires the landing to have a length not less than the width of the stairway.
- Stair Nosing: According to IBC, the nosing should not be more than 1.25 inches and not less than 0.75 inches. ADA recommends that nosings be beveled or rounded and visually contrasted from the rest of the tread to prevent tripping hazards.
- Guards and Balusters: The IBC requires guards to be a minimum of 42 inches high, and openings in balusters should not allow the passage of a 4-inch diameter sphere.
- Accessible Routes: ADA requires an accessible route to be provided where stairs are present. This may involve the inclusion of ramps, lifts, or elevators alongside the stairs.
Remember, these are broad guidelines, and the specific rules can vary depending on local building codes and the exact requirements of the ADA and IBC. Always consult with a professional or local building authority when designing or evaluating L-shaped stairs for compliance.