Why are more architects turning to GRC over traditional precast concrete to enhance exterior facade design?

Shaun Henley, Managing Director and Founder of Henley Group, explains why more architects are turning to GRC over traditional precast concrete to enhance exterior facade design.

Why more building designs are opting for GRC

Glass Reinforced Concrete (GRC) is increasingly growing in popularity among architects and designers as the material of choice for exterior cladding, compared to traditional precast concrete. GRC is a more viable and attractive option, due to its greater flexibility in terms of shaping a building’s design, colour and aesthetic appeal.

GRC is a composite material made up of cement, very fine aggregates, water and alkali-resistant glass fibres. The glass fibres are dispersed throughout the mix, giving the material better strength and durability compared to traditional concrete. 

The consideration of weight in structural building design

A significant factor determining structural building design is influenced by the weight of exterior facades. Architects are more often favouring the lightweight composition of GRC, recognising the opportunity it presents for more efficient structural design and overall project cost savings compared to precast concrete panels which, due to their weight, require substantial load-bearing capacity.

The lighter weight material also benefits the foundation design as smaller footings and less excavation are often required, minimising the lateral load, and alleviating structural stress on a building.

Freedom to be creative with design

Perhaps even more attractive to architects and designers is the versatility of GRC. It can be easily moulded into various shapes, sizes and colours, allowing flexibility for architects to create many styles and designs in exterior facades. This gives architects unparalleled freedom to create complex designs that would be challenging or impractical with traditional pre-concrete. Whether architects are looking to create curved or undulating shapes, GRC enables more flexibility to achieve an artistic vision, without overburdening the structure of buildings. GRC has the ability to replicate the look of natural stone, which can be another key advantage, when it comes to design. 

Standing the test of time

Structural durability has been a key topic within the industry and more widely in recent times. Buildings must be resistant to environmental factors, fire, and wear and tear to withstand the test of time.

The glass fibres in GRC make it highly resistant to corrosion, weathering, and other forms of degradation. Its ability to withstand harsh environmental conditions such as freeze-thaw cycles, UV radiation and chemical exposure has been a key factor in the materials growth in popularity, ensuring that an external façade maintains its appearance and structural integrity over time.

Both architects and construction experts favour materials that require minimal maintenance, as it reduces lifecycle costs. GRC has inherent durability and is resistant to corrosion, meaning it has a long lifespan and a lower need for replacements or repairs over time. 

On the other hand, traditional precast concrete can be susceptible to wear, weathering and structural deterioration, which means more periodic inspections, repairs, and potential replacements. These maintenance and repair costs can accumulate significantly over time, impacting the building’s overall financial performance.

Sustainably-led design

With sustainability at the forefront of architects’ agenda, it is important to consider environmentally friendly materials that contribute to the overall sustainability and green credentials of a building. The use of GRC panels offers many environmental benefits and has a longer lifespan compared to many other façade materials, contributing significantly to promoting responsible practices. 

Traditional precast concrete, while durable, often involves higher energy consumption during the manufacturing process, generating more waste and making it less environmentally friendly. Architects who are committed to sustainable practices can reduce their carbon footprint by opting to use GRC panels.

Building safety is paramount

Fire safety has always been imperative and in the years following the Grenfell Tower disaster, new regulations are being continuously introduced and re-evaluated. Therefore, it’s vital that architects opt for the safest and highest-quality materials when designing new buildings. GRC panels are an excellent fire-resistant option when designed and constructed as part of a robust and practical fire strategy. The material is non-combustible, preventing the spread of fires, providing added protection for occupants, and reducing the risk of fire damage.

The fire resistance, combined with the durability and longevity of GRC cladding panels, makes them a smart choice for building projects in areas with strict fire safety codes, such as high-rise buildings or commercial structures.

Long-term financial benefits

While the initial cost of GRC may be slightly higher than that of traditional precast concrete, its long-term benefits far outweigh the upfront investment. Reduced maintenance, energy savings, and an extended lifespan make GRC a financially astute choice for architects. Traditional precast concrete comes with the benefit of lower supply costs in the short-term but can incur higher long-term costs due to maintenance and repair needs. Designers who are looking to optimise their budgets and reduce ongoing financial implications should consider the overall cost-effectiveness of using GRC as an external cladding material.

Henley Group has excellent examples of using GRC to create stunning façades on stand-out commercial buildings, including the HSBC European HQ in Birmingham which involved installing 7500m2 of specialist cladding safely and efficiently. Henley Group is also established in the Middle East, consulting on some of the largest GRC projects in the world.

As structural building design continues to evolve and sustainable practices become paramount, we can expect to see GRC continually acknowledged as a superior alternative to traditional precast concrete as an external façade material. Architects can confidently opt for this material to bring their designs to life, while ensuring the building stands the test of time, both in terms of its aesthetic appeal and performance.