Hemp in construction - The Hempcrete Topic: Designing and Building with Hemp-lime - page 23

The shiv that Hemp Technology Ltd processed for use in construction was sold on to the
market exclusively by the parent company, Lime Technology Ltd, as Tradical ® HF and
was marketed as part of the Tradical ® Hemcrete ® system together with Tradical ® HB, the
hempcrete binder made by industrial lime producer Lhoist, which Lime Technology has
the exclusive rights to supply within the UK. To date it has not been possible to purchase
Tradical ® HF without the equivalent binder, or vice versa, in the UK, and so this has arti-
ficially restricted the supply of hemp shiv on to the UK market. However, this may soon
change in the light of the current situation at Hemp Technology.
Those wishing to source UK-grown hemp from other suppliers have been restricted to a
small number of independent farmers who had not signed exclusive supply contracts with
Hemp Technology, and who process their own hemp.
There is nothing to stop builders making links with farmers and sourcing their own shiv
for building, but if the farmer is not used to supplying to the construction industry it is
important that the essential qualities of hemp shiv for construction are understood by both
parties. There needs to be clear agreement in advance about the qualities of the product
required (as described earlier) and the cost, including that of transportation to site. Some
natural building suppliers supply hemp shiv from independent UK farmers, although this
is far from commonplace at the time of writing.
In early 2013 the French company Chanvrière de l'Aube commenced talks with several
natural building suppliers in the UK about supplying its hemp shiv through these outlets.
Samples shown to the authors were encouraging in terms of the shiv having a very good
standard of dryness, a very low dust and fines content, and a consistent colour. However,
broad discussions around price suggested that it might be more expensive than shiv cur-
rently on the UK market.
It remains to be seen whether importing French hemp shiv into the UK is a commercially
viable enterprise. Such imports do not help the development of the (less well-established)
hemp-processing sector in the UK, and the use of foreign shiv would make hempcrete less
sustainable, since locally grown UK hemp (with, therefore, lower embodied energy - the
energy used in sourcing, manufacture and transport of a material) is available for UK build-
ers to use. On the other hand, the presence on the market of French shiv, subject as it is to
the more stringent standards imposed by the French authorities, may prove competitive to
UK shiv producers in terms of quality, if not price, and may provide the required impetus
for the UK industry to develop its own quality standards for construction hemp shiv.