The hempcrete wall: an overview - The Hempcrete Topic: Designing and Building with Hemp-lime - page 225

long as it is at least as vapour permeable as the hempcrete behind it (preferably more so),
and although lime is the norm, clay plasters can be an attractive alternative.
Lime plastering or rendering is a distinct skill, with certain important differences in tech-
nique compared with the application of cement render and gypsum plaster, and it is import-
ant that the people doing this work have the necessary skills and experience. There is no
reason why a plasterer should not be competent in both lime and gypsum, but very few are,
as the use of gypsum is so ubiquitous across the UK. Assuming that a gypsum plasterer can
work with lime (or vice versa) can result in mistakes that are costly to correct. The fact that
the application of lime plaster requires some specialist knowledge, and a more thoughtful
approach than the application of gypsum or cement, means that a competent lime plasterer
may be harder to find and more expensive than a plasterer for standard gypsum work.
For more about the finishes for hempcrete walls, see Chapter 18 .
Services
The supply of water, gas and electricity to a hempcrete building requires exactly the same
skills and encounters the same issues as supplying these services to any other property. The
only slight advantage hempcrete brings is the potential of the monolithic wall to reduce the
work of plumbers and electricians. In a hempcrete wall there are no obstructions to ser-
vices from additional layers (e.g. membranes) in the wall build-up, so the construction of a
services void is not necessary, and services can be run within the wall as soon as the frame
is constructed, before the hempcrete is cast.