Constructing staircases is a fundamental aspect of building superstructure works, crucial for enabling safe and efficient vertical movement within structures. In Kenya, staircases must accommodate diverse building uses, from residential apartments in Nairobi to public offices in county government buildings, necessitating careful attention to design, materials, and compliance with building codes. This chapter explores the technical and regulatory requirements for staircase construction, ensuring that building technology professionals deliver safe, durable, and functional staircases.

2.1 Stair's Construction

Staircase construction involves understanding specific terminology, adhering to building codes, applying design principles, selecting appropriate types of stairs, and choosing suitable materials. Each of these components plays a critical role in ensuring that staircases are safe, accessible, and compliant with Kenyan standards and international best practices.

2.1.1 Terms

Understanding staircase terminology is essential for clear communication, accurate design, and effective construction. These terms define the components and measurements that professionals must master to create functional staircases.

Tread

The tread is the horizontal part of a stair on which a person steps. Its depth directly affects comfort and safety; a tread that is too narrow can cause slipping or missteps, while an overly wide tread may waste space. In commercial buildings such as hotels in Mombasa, treads typically measure between 250mm and 300mm to accommodate high foot traffic safely.

Riser

The riser is the vertical component between two treads. The height of the riser influences the ease of climbing; a riser that is too tall can cause fatigue, while one that is too short may feel awkward. Kenyan building codes recommend risers to be between 150mm and 180mm for optimal ergonomics, as observed in office blocks in Nairobi’s CBD.

Nosing

The nosing refers to the edge of the tread that protrudes beyond the riser below. It enhances safety by increasing the effective tread depth and providing better foot placement. Proper nosing design is critical in public hospitals such as Kenyatta National Hospital, where patient and visitor safety is paramount.

Flight

A flight is a continuous series of steps without a landing. Flights must be designed to avoid excessive height or length, which can cause user fatigue or pose safety risks. In multi-storey schools, flights are often limited to 12-14 steps before a landing is introduced.

Landing

A landing is a flat platform between flights that provides rest and changes the direction of the stairs. Landings improve safety and accessibility, especially in public buildings like county government offices, where staircases must accommodate diverse user needs including persons with disabilities.

2.1.2 Building Code Requirements

Compliance with building codes ensures that staircases meet minimum safety, accessibility, and structural standards. Kenya’s Building Code and the National Construction Authority guidelines provide detailed requirements to protect users and maintain structural integrity.

Dimensions and Proportions

Building codes specify minimum and maximum dimensions for risers, treads, and landings to standardize comfort and safety. For instance, the Building Code of Kenya mandates risers between 150mm and 180mm and treads not less than 250mm. These dimensions prevent accidents and facilitate smooth movement in institutions like universities.

Handrails and Guardrails

Handrails must be provided on at least one side of staircases with widths less than 1.2 meters and on both sides if wider. Guardrails prevent falls from open sides of stairs and landings. In public libraries and banks, robust handrails and guardrails protect users and comply with occupational safety regulations.

Headroom Clearance

Building codes require a minimum headroom clearance, usually not less than 2 meters, to prevent users from hitting their heads while ascending or descending. This is particularly relevant in tight stairwells of older buildings undergoing renovation in Nairobi’s central business district.

Accessibility Provisions

Codes mandate stair design to incorporate features for persons with disabilities, such as tactile warning strips and contrasting nosing colors. For example, in county hospitals, these features enhance accessibility and comply with the Persons with Disabilities Act in Kenya.

Fire Safety Measures

Staircases in commercial and public buildings must serve as safe evacuation routes, requiring fire-resistant materials and clear signage. Buildings like shopping malls in Kisumu incorporate fire-rated stair enclosures to meet fire safety regulations.

2.1.3 Design Requirements

Effective staircase design balances functionality, safety, aesthetics, and space efficiency. Designers must consider user demographics, building function, and structural constraints.

Ergonomics and Comfort

Designing stairs with appropriate riser and tread dimensions reduces user fatigue and risk of accidents. In schools, for example, staircases with uniform step heights and non-slip surfaces ensure children’s safety during peak movement times.

Structural Stability

The design must ensure that staircases can support expected loads, including dynamic loads from users. Reinforced concrete stairs in county government offices are typically designed to withstand heavy usage over long periods without structural degradation.

Space Optimization

Effective use of available space is critical, especially in urban environments with limited floor area. Spiral staircases in boutique hotels in Nairobi exemplify space-saving designs that also provide aesthetic appeal.

Aesthetic Integration

Staircases often serve as architectural features; their design should complement the building’s style. For instance, timber stairs with ornate balustrades in heritage hotels blend functionality with cultural aesthetics.

Safety Features

Incorporating anti-slip finishes, proper lighting, and handrails enhances safety. Retail outlets in Nairobi integrate LED lighting along stair edges to improve visibility during night hours.

2.1.4 Types of Stairs

The choice of staircase type depends on factors such as space, function, aesthetics, and budget. Different types serve different building needs and user volumes.

Straight Stairs

Straight stairs consist of a single flight without changes in direction. They are simple to construct and economical, commonly used in residential buildings and small offices in Nakuru.

Quarter-Turn Stairs

Quarter-turn stairs change direction 90 degrees, typically with a landing. They fit well into corner spaces and are common in multi-storey schools where space constraints exist.

Half-Turn Stairs

Half-turn or U-shaped stairs include a 180-degree turn with a landing, allowing efficient use of space and easier ascent. County government offices in Eldoret often have such stairs for ease of access.

Spiral Stairs

Spiral stairs wind around a central pole, offering compactness and visual interest. They are suitable for small spaces but less convenient for high traffic, seen in boutique hotels in coastal towns.

Bifurcated Stairs

Bifurcated stairs split into two flights from a wide landing, often used in grand public buildings such as universities to manage large crowds and create imposing entrances.

2.1.5 Materials

The selection of materials for staircases affects durability, maintenance, cost, and aesthetics. Materials must align with the building’s function and environmental conditions.

Concrete

Concrete is durable, fire-resistant, and adaptable for various designs. It is widely used in public institutions such as county hospitals due to its longevity and low maintenance needs.

Timber

Timber offers aesthetic warmth and is easier to work with but requires protection against moisture and termites. In residential buildings around Kisumu, timber stairs remain popular for their natural appearance.

Steel

Steel allows slender, strong structures and supports modern designs. Commercial office blocks in Nairobi use steel stairs for their sleek look and capacity to span longer distances without intermediate supports.

Stone and Marble

Stone and marble provide elegance and durability but are costly and heavy. High-end hotels in Mombasa often feature marble stairs to convey luxury and permanence.

Composite Materials

Composite materials combine properties such as strength and weather resistance, used increasingly in external staircases at retail outlets where exposure to elements is significant.

Chapter Summary

This chapter covered the essential aspects of constructing staircases, beginning with the key terms used in stair construction to establish a clear understanding of the components involved. It then addressed the building code requirements that ensure staircases meet safety and accessibility standards crucial for user protection. The design requirements section detailed the necessary dimensions and ergonomics to achieve functionality and comfort. Various types of stairs were examined, highlighting their structural differences and appropriate applications in different building contexts. The chapter concluded with a discussion on the materials commonly used in staircase construction, emphasizing their properties and suitability for different stair types. Together, these topics provide a comprehensive foundation for planning and executing staircase construction in line with regulatory and practical demands.

Am I competent?

At the start of this chapter we promised you would be able to:

• Wear the correct personal protective equipment and follow safety procedures for staircase construction jobs.
• Identify and prepare the tools and equipment needed for wall construction with accuracy.
• Read working drawings to accurately identify the type of upper floor required for the project.
• Select and prepare the tools and equipment needed for upper floor construction correctly.
• Prepare upper floor construction materials precisely according to job requirements.
• Safely erect formwork for staircases, following the National Building Code 2024 standards.
• Install the upper floor correctly, ensuring compliance with the National Building Code 2024 requirements.
• Strike off formwork safely and in accordance with the National Building Code 2024 standards.
• Carry out proper curing of the upper floor as specified by the National Building Code 2024.

Tick each one you can genuinely do.

So, are you there yet?

You're competent when you can confidently do 50% or more of what this chapter promised.

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