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Evaluating the Thermal Conductivity of Hemp-Based Insulation.
Thomas Fiedler1, James Pedersen2
1School of Engineering, The University of Newcastle, Callaghan 2308, Australia.
Materials (Basel, Switzerland)
|May 7, 2025
Summary
Hemp-based insulation materials show good thermal conductivity (0.055-0.065 W/mK). While having higher conductivity than conventional materials, their thermal resistance (R-value) can be matched by increasing thickness.
Area of Science:
- Building Science
- Materials Science
- Sustainable Construction
Background:
- Growing demand for eco-friendly insulation materials.
- Need to understand thermal properties of natural fiber composites.
- Hemp hurd and fiber are abundant, renewable resources.
Purpose of the Study:
- To evaluate the thermal conductivity of hemp-based insulation.
- To investigate the impact of fibre-to-hurd ratio and bulk density.
- To compare hemp insulation performance with conventional materials.
Main Methods:
- Transient Plane Source (TPS) measurements for thermal conductivity.
- Testing of hemp-based insulation samples from various suppliers.
- Analysis of varying fibre-to-hurd ratios and bulk densities.
Main Results:
- Measured thermal conductivities ranged from 0.055 to 0.065 W/mK.
- Higher sample compression increased bulk density and thermal conductivity.
- Hemp insulation exhibited roughly double the thermal conductivity of glass wool and polystyrene.
Conclusions:
- Hemp-based insulation offers viable thermal performance.
- Thickness adjustment can achieve equivalent thermal resistance (R-value).
- Further research into optimizing hemp insulation properties is warranted.
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