Indicative detailing - The Hempcrete Topic: Designing and Building with Hemp-lime - page 559

Figure 32. Hempcrete insulation in a flat roof.
Hempcrete in ceilings
When using hempcrete roof insulation, it is important that the whole roof build-up is
breathable, including the interior finish. If the roof space is to be used as a room, with a
ceiling on the inside of the rafters, this can be achieved by using either a breathable plaster
carrier board or a cast hempcrete ceiling coupled with a breathable finish. A hempcrete
ceiling is constructed as a cast-in-situ structure from above and requires a layer of wall-mix
hempcrete, firmly compacted and reinforced with timber battens to create a ceiling board.
The lower-density hempcrete roof insulation is then placed on top of this (see Figure 33 ) .
See Chapter 17, pages 226 , for full details.