We are in a digital era defined by relentless data generation. Whether processing financial transactions, streaming videos, managing smart buildings, or training artificial intelligence models, data centres sit at the epicentre of our modern lives. Global spending on data centres is projected to surpass $1 trillion in the coming years, driven by exponential growth in cloud computing, AI, and digital transformation¹.
However, as data centres flourish both in scale and mission-critical importance, a vital question must be asked: Are we building them safely and sustainably enough to withstand the risks of today and tomorrow?
The fire risk facing the digital economy
Recent data centre fires have highlighted the potential fragility of even the most advanced facilities. In March 2021, a major fire at the OVHCloud facility in Strasbourg destroyed one building and rendered another inoperable. Millions of websites, including government, banking and news platforms, were disrupted. Similarly, in March 2023, a fire triggered by a water leak and subsequent UPS failure led to a multi-cluster shutdown at Google Cloud’s facility in Paris, severely affecting over 90 cloud services.
These aren’t isolated incidents. According to the Uptime Institute, over 60% of data centre outages cost more than $100,000, with many exceeding $1 million². The average cost of data centre downtime now stands at roughly $9,000 per minute³. Beyond the financial toll, outages directly impact public trust and operational continuity for businesses and institutions alike.
Mitigating this risk begins with smarter design. A critical line of defence lies in passive fire protection built directly into the structure, especially the building envelope. Enter non-combustible stone wool sandwich panel insulation.
Prioritising fire resistance
Stone wool, made from molten volcanic rock, is inherently non-combustible, withstanding temperatures above 1,000°C. When used as the insulating core in sandwich panels, it creates a robust fire-resistant barrier within the building façade, and partition walls.
Classified A2-s1, d0 under EN 13501 standards, stone wool sandwich panels do not propagate flames or emit toxic smoke. This crucial feature buys valuable time for evacuation, emergency response and system failover, minimising both damage and danger. These panels maintain structural integrity under fire, slowing the spread and compartmentalising risk.
This passive protection is essential in a world where emerging technologies introduce new fire threats: from lithium-ion batteries to high-intensity computing loads to, most notably, rooftop solar installations.
Sustainable intent; managed risk
As part of sustainability commitments, data centre operators are increasingly deploying rooftop solar photovoltaic (PV) arrays. While this transition to renewable energy is commendable, it introduces unintended risk.
Solar panel fires are on the rise. A 2020 study by BRE National Solar Centre in the UK found that fire incidents involving PV systems, often due to faulty connectors, poor installations, or panel malfunctions. are more common than previously thought⁴. Fires originating from faulty rooftop solar installations can rapidly spread across combustible roofing elements, threatening the entire facility and all the data it protects.
Making a data centre ‘green’ should not introduce hazardous vulnerabilities. We must ensure sustainability drives are themselves sustainable in every dimension, including fire resilience.
Energy performance and thermal efficiency
Beyond fire safety, stone wool-enhanced sandwich panels provide substantial energy efficiency benefits, which are especially critical given that data centres currently consume 2% of global electricity; a figure expected to rise to 9% by 2030⁵.
High-density stone wool insulation reduces thermal transfer, enhancing the stability of internal environments while lowering the demand for active HVAC solutions. As thermal displacement is limited, cooling loads are reduced, which is vital in high-density racks consuming upwards of 60kW each due to AI workloads⁶. These panels also support green roofing systems, aiding cooling and stormwater management while mitigating the urban heat island effect.
In the pursuit of net-zero or carbon-neutral operations backed by solar, wind, and battery storage, sandwich panels with stone wool insulation align with green design goals while maintaining operational integrity.
Modularity and the construction advantage
Modern data centres must not only be sustainable but scalable. Here, sandwich panel systems support industrialised, off-site construction approaches that favour speed, precision, and adaptability.
Dry construction systems using prefabricated sandwich panels allow architects and engineers to rapidly deploy high-performance building envelopes. Modularity simplifies future expansion as hardware evolves or leasing needs shift, supporting the ‘growth on demand’ model more sustainably.
Moreover, stone wool’s longevity and recyclability add to the lifecycle value. At end-of-life, steel panel facings and stone wool cores can be recovered and reused, contributing to circular design principles.
Reactivity to resilience
Clearly, the best fire is the one that never spreads. In addition to shaping a building’s environmental performance, materials selection defines a data centre’s passive resilience. When considering the extreme financial penalties of outages, asset loss, destroyed equipment, and reputation damage, the return on investments in non-combustible materials becomes evident.
Data centre operators also face evolving insurance landscapes. Premiums covering data centre facilities — some of which cost over $1 billion to construct — are rising steadily. Insurers are becoming wary of poorly mitigated fire and downtime risks7. Integrating flame-resistant solutions like stone wool can reduce exposure, making facilities more insurable and financially sound.
Safeguarding the vision
In a time when digital continuity directly impacts public safety, economic stability, and social interaction, we must rigorously audit the backbone of our digital infrastructure. whether from conventional hazards or next-generation upgrades like rooftop solar, fires can undo sustainability progress and disrupt millions of lives.
As architects, engineers, and developers, we have a duty to shift from reactive risk response to proactive resilience. That means designing structures for both durability and flexibility, which are prepared to embed clean energy systems without fire vulnerability.
With stone wool core for sandwich panels, ROCKWOOL Core Solutions supplies an indispensable tool for enabling this change. They provide thermal performance, acoustic comfort, structural flexibility, and most vitally, unrivalled passive fire protection — without compromising sustainability. For data centres tasked with delivering 24/7 uptime in a carbon-constrained future, this is not a compromise. It’s a new standard.
Read more about the technology in Building with stone wool insulated sandwich panels.
Sources:
1. CBRE Data Centre Trends Report, 2023
2. Uptime Institute Annual Global Data Center Survey, 2023
3. Ponemon Institute: Cost of Data Center Outages
4. BRE National Solar Centre: Fire and Solar PV Systems Report, 2020
5. International Energy Agency (IEA), Data Centre Energy Report, 2023
6. Schneider Electric: AI and High-Density Rack Trends, 2024
7. Marsh: Construction Insurance Insights — Data Centres Report, 2024
About the Author: Daniela Pasquero holds a degree in Civil Engineering from Politecnico of Turin and a PhD in Mechanics of Materials from Ecole Nationale des Ponts et Chaussées.
