In October of 2019, Hempitecture collaborated with an architectural team, with architect of record as Mell Lawrence Architects, to detail and build hempcrete wall mockups. Small scale mockups can be useful to see different construction techniques and strategies on a small scale, before a full size project is built.
Mell Lawrence Architects beautifully detailed 2 different styles of hemp lime wall assemblies:
1) Frame on Center
2) Frame to Outside
Both wall sections have their advantages and are used for particular instances. The first style, “frame on center” is often used in conjunction with cast in place and is the most “pure” approach to hempcrete, if there is such a thing. The structural frame, generally wood framing, is buried into the center of the wall and the hempcrete wall is plastered on both sides. With this technique, there is no thermal bridging and the mass of the wall itself becomes the defining feature of this technique. Windows are centered and installed on the structural frame, with detailing cognizant of window water draining.
Frame to the Outside refers to a structural frame, shifted to one side of the overall width of the hempcrete wall. This technique might be used if you were planning on attaching siding with a rainscreen detail, or having some sort of shear panel. For instance, with your frame shifted to outside, you could nail structural sheathing or a vapor permeable shear, such as a magnesium oxide board, directly to the studs. From a forming perspective, your form board can be placed directly against your studs, which can be a quicker way of casting hempcrete.
These are just two ways a hempcrete wall can be detailed. There is a lot of variation on how your wall should be detailed and the specifics of that will relate to your overall strategy, including finish options, location, and more. Building with hempcrete is possible and efficient with good project planning.
After: Frame on Center
After: Frame to Outside
Are you ready to start your process?
If you have a project in mind and would like to book time with Hempitecture, schedule a call with us.