PVC and Fire Safety
Fire safety isn’t just a regulation — it’s a responsibility.
Across industries, forward-thinking companies are stepping up, recognizing that protecting people and property from fire is not just smart — it’s essential. While fires in industrial buildings can lead to devastating financial losses, the true cost is measured in human lives and safety.
At the heart of every resilient building is a roof designed not only to endure the elements, but to stand strong in the face of fire. On this page, we explore the key principles of fire safety for large, flat roofs — and why PVC waterproofing membranes are a trusted choice for those who refuse to compromise on safety.
Discover how thoughtful design, smart material choices, and proven solutions can make all the difference — and help you build not just a roof, but peace of mind.
4 Facts Why PVC Roofing Is a Fire-Safe Choice
1. Safe Installation
Installed using hot-air welding (450–600°C), no open flames required.
Greatly reduces fire risk during installation.
2. Low Fire Load
PVC has a much lower fire load than traditional bitumen membrane.
Slows fire spread and reduces heat release.
3. Fire Performance
Does not spread flames or produce flaming droplets.
Meets BROOF(t2) classification and available with FM approval.
4. Ideal for Solar Roofs
Safe base for solar panels when used with PIR or mineral wool insulation.
Proper panel placement enhances fire safety.
Improving Fire Safety of Large Flat Roofs
Fire safety is a critical aspect of roof design. Reducing fire load is one of the most effective ways to improve safety. Choosing materials that burn slowly—or not at all—can significantly delay fire spread. Fire safety planning must be holistic, covering the entire structure to ensure buildings are safer and more resilient in the event of a fire.
Regulations on Building Fire Safety
According to Section 28 of the Finnish Building Fire Safety Regulation:
“Fire must not spread in the roofing or its substrate in a way that poses a danger.”
This means structures must prevent fire from spreading in a way that endangers people or property. If insulation materials with a fire class lower than A2-s1, d0 are used, the roof must be divided into 2,400 m² fire compartments using fire breaks.
Additionally, if the building has a fireplace or is in a wildfire-prone area, the roofing must meet the BROOF(t2) classification. However, BROOF(t2) is a small-scale test and may not fully reflect large-scale fire behavior.
Understanding Fire: How Fires Start and Spread
Fire requires three elements: oxygen, heat, and fuel. When these are present in sufficient quantities, a self-sustaining chain reaction occurs. Ignition happens when materials exceed their ignition temperature.
Common causes of roof fires include electrical faults (such as issues with solar power systems), external fire sources (like nearby structures or waste bins), internal ignition sources (including production processes, fireplaces, or chimneys), and natural events (such as lightning strikes or fireworks).
Roofs typically have ample oxygen, and ventilation can feed fires even through cavities.
Fire Load in Roof Structures
Fire load refers to the amount of combustible material present in a structure and plays a critical role in determining how a fire behaves. In roofing systems, fire load can originate from within the structure itself or from external sources, such as debris or stored materials left on the roof.
The type of materials used in the roof assembly significantly affects fire performance. Materials that form a dense, charred surface tend to resist fire better than those that release flammable gases or liquids when exposed to heat.
In renovation projects, building guidelines typically allow for the addition of up to two new roofing layers before a complete replacement is mandatory. However, in practice, this limit is often exceeded due to the challenges associated with removing old bitumen layers. Each additional layer increases the overall fire load, which can accelerate fire spread and intensify damage.
PVC roofing systems offer a clear advantage in this regard. With a substantially lower fire load compared to traditional bitumen-based systems, they help slow the spread of fire, reduce peak temperatures, and make firefighting efforts more manageable. This not only enhances safety but also minimizes structural damage and supports faster recovery after an incident.
Fire-Safe Installation of Waterproofing Membranes
Roofing and waterproofing involve hot work, classified as high-risk by Finnish rescue authorities. A hot work permit is required, issued by a certified person.
Open flames during installation significantly increase fire risk. According to SPEK (Finnish National Rescue Association), 25–40 roof fires occur annually due to hot work. However, no fires have been reported from PVC roof installations in Finland in the past 35 years.
PVC installation uses hot-air welding—no open flames. The equipment operates at 4–6 kW, and the air cools quickly, making the process inherently safer.
Cavities and Roof Fire Safety
Cavities in roof structures (e.g., eaves, ventilation gaps) can act as fire channels. Dust or sawdust in cavities can ignite easily, and fires in enclosed spaces are harder to detect and extinguish.
Proper fire stops are essential to prevent fire spread within cavities. Ventilation can also feed oxygen to the fire, accelerating its growth.
Solar Power Systems and Fire Safety
The EU Solar Rooftop Initiative mandates solar installations on all new public buildings and non-residential buildings over 250 m² starting in 2027. This will significantly increase rooftop solar systems.
A qualified installer ensures safe and correct installation. Fire safety must be considered when integrating solar systems on PVC roofs. We provide complete solutions for new and existing PVC roofs.
The FRISSBE project offers a comprehensive fire safety guide for solar panel roofs: “Fire Safety Guideline for Building Applied Photovoltaic Systems on Flat Roofs”.
Ready to Take Fire Safety to the Next Level?
At the core of every safe and resilient building is a roof designed with intention — one that protects not just the structure, but the people within it. We're passionate about helping you build smarter, safer, and more sustainable.
Whether you're planning a new project or upgrading an existing one, our experts are here to guide you every step of the way with proven solutions and deep industry insight.
Let’s rethink what a roof can do. Let’s rethink fire safety.
