Hempcrete

Hempcrete or Hemplime is a bio-composite material, a mixture of hemp hurdles (shives) and lime (possibly including natural hydraulic lime , [1] sand , pozzolans ) used as a material for construction and insulation . [2] It is marketed under names like Hempcrete, Canobiota, Canosmose, and Isochanvre. [3] Hempcrete is easier to work with than traditional lime mixes and acts as an insulator and moisture regulator. It lacks the brittleness of concrete and does not need expansion joints . [3] The result is a lightweight insulating material.

Like other plant products, hemp absorbs CO 2 from the atmosphere as it grows, retaining the carbon and releasing the oxygen . Theoretically 165 kg of carbon can be absorbed and locked up by 1 m 3 of hempcrete wall during manufacture. [4] In addition to the carbonation of the lime during this lime turns to limestone . [5]

The typical compressive strength is around 1 MPa, [6] around 1/20 that of residential grade concrete . It is a low density material and resistant to cracking under the earthquake-prone areas. Hempcrete walls must be used together with a frame of another material that supports the vertical load in building construction, as hempcrete’s density is 15% that of traditional concrete. [7]

Limecrete, Ltd. (UK) reports a fire resistance rating of 1 hour per British / EU standards. [8]

References

  1. Jump up^ Allin, Steve. Building with Hemp, Seed Press, 2005,ISBN 978-0-9551109-0-0. (p.146, 1st Edition).
  2. Jump up^ “NNFCC Renewable Building Materials Factsheet: An Introduction” . National Non-Food Crops Center . February 21, 2008 . Retrieved 2011-02-16 .
  3. ^ Jump up to:a b Priesnitz, Rolf B. (March-April 2006). “Hemp For Houses” . Natural Life Magazine .
  4. Jump up^ “Tradical Hemcrete 2008 Information Pack” . American Lime Technology . Retrieved 2010-05-15 .
  5. Jump up^ “Minoeco – Natural Plasters & Bioclimatic Design, Hempcrete” .
  6. Jump up^ “Tradical Hemcrete 2008 Information Pack” . American Lime Technology . Retrieved 2009-08-25 .
  7. Jump up^ Flahiff, Daniel (August 24, 2009). “Hemcrete®: Carbon Negative Hemp Walls” . Inhabitat .
  8. Jump up^ Abbott, Tom (2014-04-26). “Hempcrete Factsheet” . The Limecrete Company, Ltd.