Page 15 - InnoRenew CoE International Conference 2020, Integrating Sustainability and Health in Buildings
P. 15
ting the Thermal Properties of Loose-Fill Straw Insulation
Hana Remešová1, Nathan Kotlarewski2, Matthew Schwarzkopf1
1 University of Primorska / InnoRenew Centre of Excellence, ha.rem@seznam.cz / matthew.schwarzkopf@iam.upr.si
2 University of Tasmania, ARC Centre for Forest Value, Nathan.Kotlarewski@utas.edu.au
Current research suggests that natural materials such as straw can be a suitable insulation
alternative to reduce energy demands in the construction and building industry, particularly
during service due to its excellent thermal properties, low embodied energy, carbon storage, and
acceptable mechanical properties (Chaussinand, Scartezzini, Nik, & Nik, 2015; Maraldi, Molari,
Molari, & Regazzi, 2018; Mattila, Grönroos, Judl, & Korhonen, 2012; Sabapathy & Gedupudi,
2019). Traditional construction with straw utilises the material for insulation in the form of
straw bales. The objective of this research was to test the thermal properties of straw as loose-fill
insulation in traditional wall construction to validate if its thermal performance is competitive
against readily available synthetic insulation batts.
A commercially available synthetic batt (15 kg/m3) and three straw samples of densities 31 kg/
m3, 54 kg/m3, and 69 kg/m3 were tested between two chambers fitted with thermocouples to
measure the increase in heat from a heated chamber to the adjacent chamber over a set time. The
results aligned with the literature, noting the insulation properties of the straw were dependent
on density; even the sample with the lowest density (31 kg/m3) acted as an insulator to the
adjacent chamber. The highest density sample (69 kg/m3) resulted in the lowest temperature
increase of 0,95°C (20,7°C to 21,65°C) compared to the synthetic batt, which prevented any
increase in temperature of the adjacent chamber. This study suggests that the use of straw
presents a plausible future application in the construction industry as a natural material for
insulation in buildings. When sourced locally, it has low environmental impact and lower
costs associated with transportation. However, future research and development is required to
determine a standardised building material for its use in build-ings.
Keywords: straw, insulation, loose-fill, energy efficiency
Acknowledgements: This research was funded by the Australian Research Council, Centre for
Forest Value, University of Tasmania, TAS, Australia, grant number IC150100004. The authors
gratefully acknowledge the European Commission for funding the InnoRenew project (Grant
Agreement #739574) under the Horizon2020 Widespread-Teaming program and the Republic of
Slovenia (investment funding from the Republic of Slovenia and the European Union's European
Regional Development Fund).
REFERENCES
Chaussinand, A., Scartezzini, J.-L., Nik, V. M., & Nik, V. M. (2015). Straw bale: A Waste from Agriculture, a New
Construction Material for Sustainable Buildings. Energy Procedia, 78, 297-302. Obtained 8th October 2019, from
https://sciencedirect.com/science/article/pii/s1876610215023784
Maraldi, M., Molari, L., Molari, G., & Regazzi, N. (2018). Time-dependent mechanical properties of straw bales for
use in construction. Biosystems Engineering, 172, 75-83. Obtained 8th October 2019, from https://sciencedirect.com/
science/article/pii/s1537511018302599
Mattila, T., Grönroos, J., Judl, J., & Korhonen, M.-R. (2012). Is biochar or straw-bale construction a better carbon
storage from a life cycle perspective? Process Safety and Environmental Protection, 90(6), 452-458. Obtained 8th
October 2019, from https://sciencedirect.com/science/article/pii/s0957582012001188
Sabapathy, K. A., & Gedupudi, S. (2019). Straw bale based constructions: Measurement of effective thermal transport
properties. Construction and Building Materials, 198, 182-194. Obtained 8th October 2019, from https://sciencedirect.
com/science/article/pii/s0950061818329489
INTEGRATING SUSTAINABILITY AND HEALTH IN BUILDINGS THROUGH RENEWABLE MATERIALS
15
Hana Remešová1, Nathan Kotlarewski2, Matthew Schwarzkopf1
1 University of Primorska / InnoRenew Centre of Excellence, ha.rem@seznam.cz / matthew.schwarzkopf@iam.upr.si
2 University of Tasmania, ARC Centre for Forest Value, Nathan.Kotlarewski@utas.edu.au
Current research suggests that natural materials such as straw can be a suitable insulation
alternative to reduce energy demands in the construction and building industry, particularly
during service due to its excellent thermal properties, low embodied energy, carbon storage, and
acceptable mechanical properties (Chaussinand, Scartezzini, Nik, & Nik, 2015; Maraldi, Molari,
Molari, & Regazzi, 2018; Mattila, Grönroos, Judl, & Korhonen, 2012; Sabapathy & Gedupudi,
2019). Traditional construction with straw utilises the material for insulation in the form of
straw bales. The objective of this research was to test the thermal properties of straw as loose-fill
insulation in traditional wall construction to validate if its thermal performance is competitive
against readily available synthetic insulation batts.
A commercially available synthetic batt (15 kg/m3) and three straw samples of densities 31 kg/
m3, 54 kg/m3, and 69 kg/m3 were tested between two chambers fitted with thermocouples to
measure the increase in heat from a heated chamber to the adjacent chamber over a set time. The
results aligned with the literature, noting the insulation properties of the straw were dependent
on density; even the sample with the lowest density (31 kg/m3) acted as an insulator to the
adjacent chamber. The highest density sample (69 kg/m3) resulted in the lowest temperature
increase of 0,95°C (20,7°C to 21,65°C) compared to the synthetic batt, which prevented any
increase in temperature of the adjacent chamber. This study suggests that the use of straw
presents a plausible future application in the construction industry as a natural material for
insulation in buildings. When sourced locally, it has low environmental impact and lower
costs associated with transportation. However, future research and development is required to
determine a standardised building material for its use in build-ings.
Keywords: straw, insulation, loose-fill, energy efficiency
Acknowledgements: This research was funded by the Australian Research Council, Centre for
Forest Value, University of Tasmania, TAS, Australia, grant number IC150100004. The authors
gratefully acknowledge the European Commission for funding the InnoRenew project (Grant
Agreement #739574) under the Horizon2020 Widespread-Teaming program and the Republic of
Slovenia (investment funding from the Republic of Slovenia and the European Union's European
Regional Development Fund).
REFERENCES
Chaussinand, A., Scartezzini, J.-L., Nik, V. M., & Nik, V. M. (2015). Straw bale: A Waste from Agriculture, a New
Construction Material for Sustainable Buildings. Energy Procedia, 78, 297-302. Obtained 8th October 2019, from
https://sciencedirect.com/science/article/pii/s1876610215023784
Maraldi, M., Molari, L., Molari, G., & Regazzi, N. (2018). Time-dependent mechanical properties of straw bales for
use in construction. Biosystems Engineering, 172, 75-83. Obtained 8th October 2019, from https://sciencedirect.com/
science/article/pii/s1537511018302599
Mattila, T., Grönroos, J., Judl, J., & Korhonen, M.-R. (2012). Is biochar or straw-bale construction a better carbon
storage from a life cycle perspective? Process Safety and Environmental Protection, 90(6), 452-458. Obtained 8th
October 2019, from https://sciencedirect.com/science/article/pii/s0957582012001188
Sabapathy, K. A., & Gedupudi, S. (2019). Straw bale based constructions: Measurement of effective thermal transport
properties. Construction and Building Materials, 198, 182-194. Obtained 8th October 2019, from https://sciencedirect.
com/science/article/pii/s0950061818329489
INTEGRATING SUSTAINABILITY AND HEALTH IN BUILDINGS THROUGH RENEWABLE MATERIALS
15
