Can You Incorporate Natural Stone In A Thermal Mass Bench?

Designing with Thermal Mass

When incorporating natural stone into a thermal mass bench, consider the thermal conductivity and density of the stone. For example, a 4-inch thick slab of limestone has a thermal conductivity of 0.79 W/mK, which is higher than concrete (0.22 W/mK). Choose a stone that is dense and has a high thermal mass, such as granite or basalt.

Building the Bench

To build the bench, start by laying a foundation of compacted gravel or sand. Then, lay a layer of insulation, such as rigid foam board, to reduce heat loss. Next, place the thermal mass bench, which can be made from a combination of concrete and natural stone, on top of the insulation. For a typical bench, use a 1:1:3 mix of cement, sand, and gravel, with 20% natural stone aggregate. A 4-foot long bench with a 4-inch thick slab of thermal mass can store approximately 1 kWh of heat energy.

Tips and Considerations

When designing a thermal mass bench with natural stone, consider the color and texture of the stone to create a visually appealing design. Also, ensure that the stone is properly sealed to prevent water damage and improve durability. Finally, consider adding a layer of finish coat, such as a clear epoxy resin, to protect the stone and enhance its thermal mass properties.