Fireproof Insulation Exterior Board

Jason Building Materials is a manufacturer and supplier of fireproof exterior insulation boards, offering high-quality service and technical support.

These boards feature a high-purity, inorganic, non-combustible core, with surface finishes treated for high-temperature fire resistance; their dense, robust structure and high hardness make them suitable for long-term outdoor use.

What is Fireproof Insulation Exterior Board?

Fireproof insulation exterior board is an exterior wall panel with building fire safety as the primary design objective.

Its difference from ordinary insulation decorative boards lies in the selection of non-combustible or higher-grade flame-retardant core materials, and the overall structural design considers no molten dripping, no toxic smoke generation and no flame spread support under fire conditions.

In the event of a fire, these boards can buy more time for fire rescue and slow the speed of fire spreading upward or horizontally through the exterior wall.

Fire Rating & Core Material Comparison

Fire ratings and applicable scenarios for different core materials:

Class A (Non-combustible) Core Materials: Rock wool, Magnesium oxide board, Foam glass. Suitable for densely populated public buildings such as schools, hospitals and shopping malls. Key characteristics: non-combustible, no molten dripping, low smoke toxicity.

Class B1 (Difficult to ignite) Core Materials: Flame-retardant EPS board (B1 modified), Flame-retardant XPS board. Suitable for ordinary residential and industrial factory buildings. Self-extinguishing with limited combustion spread speed.

Class B2 (Combustible) Core Materials: Ordinary EPS or XPS boards. Only suitable for low-rise auxiliary buildings or temporary structures, not applicable for formal projects with strict fire acceptance.

Selection Suggestion: When local building fire codes require Class A exterior wall insulation materials, inorganic core materials such as rock wool must be selected. When Class B1 is permitted, flame-retardant organic insulation core materials can balance insulation effect and cost.

Different Core Materials: Fire & Thermal Insulation Performance

Core Advantages

1. Non-combustible Core Material: Inorganic core materials such as rock wool or foam glass maintain fiber structure without melting or shrinking even at temperatures above 1000°C. In contrast, organic insulation materials (EPS, PU) begin to melt and shrink at 200 – 300°C.

2. No Toxic Smoke: Inorganic core materials do not produce toxic gases such as carbon monoxide or hydrogen cyanide at high temperatures. This characteristic is crucial in densely populated areas (hospitals, schools, high-rise residences), most fire casualties are caused by smoke suffocation rather than flames.

3. Good Fire Sealing: Fireproof sealant is used at panel joints to prevent flame and smoke penetration through gaps to adjacent areas.

4. Balanced Insulation Function: While meeting Class A fire protection, rock wool core material has a thermal conductivity of approximately 0.040W/(m·K). Although slightly lower than PU (0.022W/(m·K)), it still meets the 75% energy saving standard.

Technical Parameters

Core Material: Rock wool (Class A1) / Foam glass (Class A1)

Core Material Density: Rock wool ≥ 100kg/m³ / Foam glass ≥ 120kg/m³

Fire Resistance Rating: ≥ 1 hour (50mm thickness) / ≥ 1.5 hours (80mm thickness)

Combustion Performance Class: Class A (GB 8624-2012)

Smoke Toxicity Class: t0 level (Safety level)

Thermal Conductivity: Rock wool 0.040W/(m·K) / Foam glass 0.050W/(m·K)

Comparison with Class B1 Insulation Boards in Fire Safety

Class B1 insulation boards can meet the difficult-to-ignite standard in single combustion tests, but still burn and release heat under continuous open flame conditions.

Class A fireproof insulation exterior boards do not burn or participate in the combustion process under open flame conditions. From the perspective of overall building fire design, exterior wall systems using Class A materials can help buildings pass stricter fire reviews.

In particular, Class 1 high-rise residential buildings over 54m, as well as hospitals, nursing homes and other buildings, current codes have mandatory requirements for Class A exterior wall insulation materials.

FAQ

Q1: How much more expensive is Class A core material compared with Class B1 core material?

A1: The price of fireproof insulation boards with rock wool core material is typically 20% – 40% higher than Class B1 PU boards of the same thickness, depending on board thickness and panel configuration.

Q2: Is rock wool core material prone to moisture absorption?

A2: Rock wool itself is a hygroscopic material, but the rock wool core in fireproof insulation boards is treated with waterproofing (silicon-based water repellent) during production, and the four edges are sealed to meet moisture-proof requirements under normal exterior wall use conditions. It is not suitable for basement exterior walls with prolonged water exposure.

Q3: Can Class A fireproof boards have stone-like finishes?

A3: Yes. The decorative panels of Class A fireproof insulation boards are no different from Class B1 boards, supporting various finish processes including fluorocarbon paint and stone-like paint.