Placing hempcrete - The Hempcrete Topic: Designing and Building with Hemp-lime - page 351

Method
The placing of hempcrete is not an exact science, owing to the non-standardized nature
of the plant-based aggregate and its low-tech method of application. Although it is by no
means a difficult task, the success of the finished cast material depends on the level of ex-
perience of those placing the hempcrete.
Always keep in mind the relationship between compaction of the placed material and even-
tual density and insulation value. There is a risk, with inexperienced or over-enthusiastic
workers, of over-tamping the hempcrete, resulting in a higher density. Not only does this
mean a lower insulation value of the finished material but it also means increased material
costs, as more hempcrete than necessary has been crammed into the void.
The challenge, especially with a large team, is to keep the density consistent across the
build. A finished wall that includes sections of differing densities is not as stable as a wall
with a consistent density throughout. For this reason it is recommended that one person, or
a very few experienced people, retain responsibility for training new workers and monitor-
ing the consistency of the placing as the build progresses.