The Cape Cod Hemp House - Graham's Perspective

The Cape Cod Hemp House is definitely one of the most interesting sites I have ever worked on. The space the building sits upon, an unparalleled piece of beach-front land in Cape Cod, is truly the most scenic place to build that you could ask for (and makes for a great view while you have your lunch). A constant ocean breeze also makes for an easier place to build in the hot summer.

However, the true interest of this project has to do with the structure that is being created there. I’ve worked on a few construction sites, but I have yet to work on a project that utilized the new and groundbreaking building systems that HempStone focuses on. The building’s general set-up includes a structural design that uses wood, laminated wood, steel, and cinder block. Inside the walls and roof, hempcrete has been spray-applied into the framing and is held in by mats of reed that are held together by metal wire. Plaster is being applied to the exterior of the building over the hempcrete, and will be applied on the building's interior in the future as well. Once this is done, wood strapping will be attached on the outside of the building as a surface for cedar shingles.

Interior framing and wall set-up on the second floor of the house

During my first week and a half of working with HempStone, I jumped right in with the construction team to work on plastering the exterior of the building. This was a completely new task for me, but one that felt like a natural progression. This past year I had learned how to install drywall and mud drywall interiors––a process that utilizes a lot of the same tools and techniques as plastering does. Plastering was a messy process that involved a lot of technique, common sense, mixing, cleaning, heights, heavy lifting, and time-management, but it was a really cool part of the build to be working on. Plaster involves a lot of time management. Concepts such as how long a plaster mix can sit before it can no longer be applied, how long the plaster should be mixed for, how long the plaster in the spray-hose used to apply the material to the building can sit before it dries and clogs, how long it takes to apply the plaster itself, how long it takes to dry, and much more definitely make for an intense and sometimes stressful situation. However, when we got the timing correct and were efficient, it was an extremely satisfying accomplishment to be a part of.

Plastering also requires a massive amount of preparation and cleanup, which goes into the building, site, and machinery. For each hour that the plaster machine was spraying, there was around 35 hours of preparation and cleanup. This would include “letting in”, which was creating sealed seams where the plaster met the corners and edges of the house. This was done by hand-plastering a material called Contega–which consists of mesh, felt, and glue–to these seams. This creates an air barrier and readies the larger wall area to be plastered. Hand mixing plaster with a drill, cleaning the mixer and hoses, setting up and taking down scaffolding, and cutting mesh pieces that go on top of the freshly plastered wall, were just a few of the other tasks required to make sure everything was ready and in place.

Spray-applying plaster on the second floor exterior walls

This project has been extremely valuable to be a part of, especially in that it is groundbreaking to see hempcrete used in this type of building situation. However, like every construction project, there are questions that arise, issues to analyze, and things to note for future projects. Although this house uses a lot of incredible methods, it also is a new structure in a place where another once stood––a situation that is always more environmentally impactful than modifying something existing. Building near the coast also brings questions and challenges related to how the landscape will be changing in the future. The house we are building luckily has systems in place to work with sea-level rise. However, the concept of building a new structure in a place that will most likely be dealing with intense landform changes is important to think about, not just in relation to this house, but also to the entire built environments we interact with here in the United States.

Despite these things, I am extremely excited about this structure. It’s been a once-in-a-lifetime experience to witness and help with this innovative and groundbreaking build at this point in its timeline, and I cannot wait to continue working on it later on this summer.