Acoustic and thermal properties of hemp-cement building materials

Effect of Blend Composition on Barrier Properties of Insulating Mats Produced from Local Wool and Waste Bast Fibres

“…Comparing the obtained test results of the noise reduction coefficient, NRC, (Figure 3) to the literature data [18,19,23,24], it can be concluded that the NRC values of mats made from sheep wool and bast fibres fall in the range of values corresponding to various materials used in construction and interior spaces. Materials such as rock wool (9 cm) (NRC = 0.90-0.95), mineral wool (5 cm) (NRC = 0.50-0.75) and a professional acoustic panel (NRC = 0.75-1.0), have significantly higher NRC coefficient values than those indicated in this study.…”

“…The noise reduction coefficient (NRC) is also used to characterise the acoustic barrier of the product. [18][19][20][21][22][23][24]. According to reports in the literature [3,[25][26][27], the noise reduction coefficient for bast fibres and wool varies in range of 0.27 to 0.69 and depends on the type of raw material and sample thickness.…”

Experimental investigation on the influence of immersion/drying cycles on the hygrothermal and mechanical properties of hemp concrete

“…That is why its current main use is limited to a infill material [15]. Studies have shown that hemp concrete is a good insulation material with good hygrothermal and acoustic properties [6,16], and it has a low thermal conductivity due to its porosity and low density. From a hygric point of view, hemp concrete is also an aerated material with high water vapour permeability [6,11,15].…”

Mechanical, thermal, hygroscopic and acoustic properties of bio-aggregates – lime and alkali - activated insulating composite materials: A review of current status and prospects for miscanthus as an innovative resource in the South West of England

“…It was reported that the absorption frequency range decreases and peaks diminish in intensity for high density composites [138]. Fernea et al [139] have studied the acoustic properties of hemp-cement composites and found the highest absorption peaks at 1000 Hz and 1500 Hz with values of 0.80 and 0.90 for shiv and fibres, respectively (b/a 2.0 and w/b 1.0). The lowest absorption coefficients reported were 0.50 and 0.65 in the 2000 -2800 Hz frequency range for shiv and fibres, respectively.…”