How does Broad Group’s B-Core steel slab compare to traditional concrete slabs?

B-Core slabs are significantly lighter (up to 10 times) and stronger (up to 100 times) than traditional concrete slabs, enabling faster assembly and better earthquake resistance.

Can modular buildings be customized architecturally?

Yes, modules can be arranged in various configurations, and interior layouts can be modified even after assembly.

What is the lifespan of a modular building?

With proper maintenance, modular buildings have a lifespan comparable to traditional buildings, often exceeding 50 years.

Are there any examples of modular buildings in Africa?

Modular construction is gaining traction in parts of Africa, with pilot projects in South Africa and Kenya focusing on affordable housing and schools.

The Technology Behind the World's Fastest-Built Story Building

The Broad Group, a Chinese manufacturing company, achieved a remarkable feat by constructing a 10-story apartment building in just 28 hours and 45 minutes in Changsha, China. This article explores the innovative technology and methods behind this rapid construction, focusing on the modular prefabrication system, materials used, and the implications for the construction industry, especially for professionals and students in Kenya's construction sector.

Building a 10-Story Structure in Under 29 Hours

The construction of a 10-story building in less than 29 hours challenges traditional timelines in the construction industry. Broad Group’s achievement is not just about speed but also about quality, sustainability, and innovation. This article unpacks how this was possible and what it means for the future of building in Kenya and beyond.

What Is Modular Prefabricated Construction?

Modular prefabricated construction involves manufacturing building components in a factory setting before transporting them to the site for assembly. Broad Group’s Living Building system uses self-contained modular units built to fit standard shipping container dimensions (12.19m x 2.44m x 3m).

Key Features:
- Factory-built modules with complete interiors (electricity, plumbing, finishes)
- On-site assembly by bolting modules together and connecting utilities
- Modules designed for easy transport worldwide using standard containers
- Flexibility in design: walls, doors, windows, and balconies can be repositioned post-construction

This system drastically reduces on-site construction time and labor costs while maintaining high quality.

How Does Broad Group Achieve Such Rapid Construction?

The speed of construction is due to a combination of:

Factory-controlled production: Modules are manufactured in a streamlined, assembly-line process similar to car manufacturing, ensuring consistency and quality.
Bolt-together modular units: On-site assembly requires only bolting modules and connecting water and electricity, eliminating traditional construction delays.
Use of cranes and a skilled workforce: Three cranes and a large team efficiently stack and secure the modules in sequence.
Pre-installed utilities and finishes: Modules arrive fully fitted with internal systems, reducing on-site work to a minimum.

Construction Step	Time Efficiency Factor	Description
Factory Module Production	Streamlined assembly line	Controlled environment minimizes errors
Transportation	Standard container size	Easy worldwide shipping and logistics
On-site Assembly	Bolt-together system	Fast installation with minimal tools
Utility Connection	Pre-installed systems	Quick hookup of water and electricity

What Materials Are Used in the Living Building?

Broad Group uses a proprietary B-Core steel slab technology for structural elements. These slabs consist of two stainless steel plates separated by hundreds of stainless steel tubes, offering:

10 times lighter weight than conventional floor slabs
100 times stronger structural integrity
Resistance to earthquakes and typhoons
Lower carbon footprint and energy consumption compared to carbon steel buildings.

This combination of lightness and strength allows for rapid assembly and the possibility of constructing buildings up to 200 stories tall using the same modular system.

How Does This Technology Address Sustainability and Energy Efficiency?

The Living Building system boasts:

Ultra-low energy consumption: Operating costs are five times less than conventional buildings.
Durability: Extremely low failure rates and high resistance to natural disasters.
Reusability: The building can be disassembled and relocated, reducing waste and allowing for flexible urban planning.

For Kenya, where sustainable construction is increasingly important, adopting such modular systems could reduce environmental impact and construction waste.

What Are the Design and Functional Advantages?

Column-less clear spaces up to 12m x 4.8m with a clear height of 2.77m allow flexible interior layouts.
Customizable modules: The position and number of walls, doors, windows, and balconies can be changed even after assembly.
Wide application: Suitable for luxury residences, public buildings, and potentially skyscrapers up to 200 floors.

Feature	Benefit	Application
Column-less spaces	Flexible interior design	Residential, commercial spaces
Modular customization	Adaptability post-construction	Renovations without demolition
Lightweight steel slabs	Easier transport and assembly	High-rise buildings and fast projects

Case Study: Broad Group’s Previous Projects

In 2012, Broad Group planned the 838m Sky City skyscraper using modular components, aiming to build it in 7 months. Although the project stalled, it demonstrated the ambition behind modular construction.
In 2015, the company built a 57-story tower in 19 days using the same Living Building system, showing scalability and speed.

Table: Comparison of Construction Methods

Aspect	Traditional Construction	Broad Group Modular Construction
Construction Time	Months to years	Hours to days
Quality Control	Variable, site-dependent	Factory-controlled, consistent
Environmental Impact	High waste and emissions	Low waste, reusable modules
Flexibility	Limited post-construction	High, modules can be modified or relocated
Cost	High labor and material costs	Lower due to efficiency and less labor

What Engineering Challenges Did Broad Group Overcome?

Building a 10-story structure in under 29 hours is no small feat. Several engineering challenges had to be addressed:

Structural Integrity: Ensuring the modular units could withstand stacking and lateral forces without traditional concrete reinforcements.
Precision Manufacturing: Modules had to be manufactured with millimeter accuracy to fit perfectly on-site.
Utility Integration: Pre-installed plumbing, electrical, and HVAC systems had to be seamlessly connected during assembly.
Safety Standards: Meeting or exceeding building codes for fire resistance, earthquake resilience, and occupant safety.

Broad Group’s B-Core steel slab technology was critical, providing a lightweight yet incredibly strong framework that could be rapidly assembled without compromising safety.

Engineering Challenge	Broad Group Solution	Impact
Structural Load Bearing	B-Core steel slabs with stainless steel tubes	High strength with low weight
Precision Fit	Factory-controlled module production	Reduced on-site errors and rework
Utility Connection	Pre-installed systems with plug-and-play design	Fast and reliable connections
Safety Compliance	Modular fireproof materials and design	Meets international safety standards

What Are the Economic Benefits of Modular Construction?

For Kenya’s construction industry, where cost and time overruns are common, modular construction offers several economic advantages:

Reduced Labor Costs: Factory production requires fewer on-site workers.
Shorter Project Timelines: Faster completion means quicker occupancy and revenue generation.
Lower Material Waste: Controlled factory environment minimizes waste.
Energy Savings: Buildings consume less energy, reducing long-term operating costs.

Economic Factor	Traditional Construction	Modular Construction (Broad Group)
Labor Cost	High due to long timelines	Significantly lower due to factory automation
Construction Time	Months to years	Hours to days
Material Waste	Up to 30% waste	Less than 5% waste
Operating Energy Cost	Standard consumption	Up to 80% energy savings

These benefits translate into more affordable housing and commercial buildings, which is critical for Kenya’s rapidly urbanizing cities.

How Does This Technology Influence Urban Development?

The ability to rapidly build high-quality buildings can transform urban planning and development:

Rapid Housing Solutions: Quickly address housing shortages in Nairobi, Mombasa, and other cities.
Disaster Relief: Provide emergency shelters that can be built and relocated quickly.
Sustainable Urban Growth: Modular buildings can be disassembled and reused, reducing urban waste.
Infrastructure Expansion: Schools, hospitals, and offices can be expanded swiftly to meet demand.

What Are the Limitations and Challenges for Adoption in Kenya?

While the technology is promising, several challenges must be considered:

Initial Investment: Setting up modular factories requires capital investment.
Skilled Workforce: Training is needed for factory workers and on-site assemblers.
Regulatory Framework: Building codes and regulations may need updating to accommodate modular construction.
Supply Chain: Reliable transportation and logistics systems are essential for module delivery.

Table: Potential Impact of Modular Construction on Kenya’s Housing Sector

Indicator	Current Status	Potential Impact with Modular Construction
Average Construction Time	12-18 months	Reduced to weeks or days
Housing Deficit	Over 2 million units	Rapid reduction through mass production
Construction Cost	High due to inefficiencies	Lower due to optimized production and labor
Environmental Impact	High waste and emissions	Reduced waste and carbon footprint