We recommend that the exterior be finished with an approved system like Baumit®. The interior may be finished with lime render, clay plaster, or lime-over-clay. Mineral colorants can be added to the render to provide a wide range of color options. Interior lime surfaces may have surface applied minerals mixed in a water solution and spray applied.
The very important thing to remember with any finish applied over hempcrete is that it must be vapor permeable- this leaves out most commercial paints. If you have any unanswered concerns about the suitability of a finish, don’t use it.