Getting the basics right - The Hempcrete Topic: Designing and Building with Hemp-lime - page 103

A note on volunteer labour
One of the many appeals of hempcrete is that costs can be kept to a minimum if volunteer
labour is used. Many self-builders sensibly take the approach of working on the job them-
selves and getting friends involved during the build. However, if volunteers are to be used
effectively, it is important to think carefully in advance about what tasks they will be asked
to do. The issue can be complicated due to volunteers often coming and going through the
course of the build rather than staying for the whole time, but it is important that some
thought is given to basic training of everyone.
Given the importance of consistently high standards of workmanship for the success of the
hempcrete material, as outlined in this chapter, it should be clear why there needs to be a
balance between free labour and experienced personnel on-site. As well as providing basic
training and an explanation of the key principles on a hempcrete build, it is important to
maintain an appropriate level of supervision over inexperienced workers, whether paid or
volunteer. At Hemp-LimeConstruct we have found that one experienced worker to three
volunteers is an effective ratio; above this, it is hard to ensure that consistent standards are
maintained.
Problems with hempcrete?
Over the past few years, as more hempcrete buildings have been built in the UK, there have
been a number of reported problems with the material, which have caused some people in
the sustainable building world to take the view that hempcrete 'doesn't work' or 'never
dries out'.
These assumptions are obviously incorrect, and all the more unfortunate since in most
cases these 'hempcrete problems' are entirely avoidable and are not the fault of the mater-
ial itself but rather of the contractor who used it. Furthermore, the vast majority of these
problems - which usually centre on slow drying of the cast material - are a short-term in-
convenience rather than a catastrophic disaster. It would be a shame for hempcrete to get a
bad name in the construction industry owing to problems that would not have occurred if
there had been proper understanding of the material, and we hope that topics such as this
one will help to prevent this.
It is true, however, that when people with little experience of lime and/or natural building
materials first try to build with hempcrete, problems can occur. Rather than ignore ex-