Thin brick itself is a non-combustible material, conforming to ASTM standards such as ASTM C1088
The thin brick system typically includes materials such as clay thin bricks, mortar, and a substrate (e.g., cement board or modular panels). Thin brick itself is a non-combustible material, conforming to ASTM standards such as ASTM C1088. However, the system’s overall fire resistance depends on the assembly, including the substrate and adhesives used. If installed with non-combustible components (e.g., cement backer board and mortar), it can be suitable for a wood-burning fireplace surround.
For specific fire resistance ratings, the assembly must be tested per standards such as NFPA 285 or similar, confirming compliance with fire safety requirements for the intended use.
R-value and K-value for Raised Hearth Application
For a raised hearth application, the R-value (thermal resistance) of the materials is essential. Foam-Control EPS, often used as insulation in modular systems, has the following properties:
- R-value per inch (at 75°F): Varies from 3.2 to 4.5, depending on the EPS density.
- K-value (thermal conductivity): Corresponds inversely to R-value and ranges between 0.22 and 0.31 W/(m·K), depending on the material grade.
If the system involves EPS or similar insulation, ensure the minimum R-value required by the fireplace manufacturer is achieved. For thin brick directly adhered to mortar or dense substrates, the R-value is lower but can be enhanced by incorporating high R-value layers beneath the finish material.
Recommendation:
Confirm all assembly components with their respective fire ratings and thermal properties to meet your fireplace manufacturer's specifications and local building codes. If unclear, consult the manufacturer or a licensed professional for an engineered solution.