An introduction to lime - The Hempcrete Topic: Designing and Building with Hemp-lime - page 65

Limes: summary
While debate has always raged (and continues to do so) in both the heritage and sustainable
building industries about which type of lime is the 'most authentic' or 'best', such argu-
ments are largely meaningless. A quick glance at the historical use of lime teaches us that
building limes were always used, as they are today, in a range of forms to suit a range of
requirements. The different characteristics of the different types of lime are each appro-
priate to different applications. The variety of limes available is perhaps best viewed as a
kind of 'toolkit' of binders for use in mortars, renders and plasters, combined with a wide
range of different materials. Anyone who claims to have a preferred form of lime is either
missing the point or only ever does one kind of work.
In considering building limes, the key issue to understand, other than the techniques in-
volved in applying lime plasters and mortars (which are varied and sometimes complex,
and beyond the scope of this topic to discuss in detail), is that of vapour permeability and
the way in which this helps to keep the building in good health. See page 58 for more on
this subject.