Hempcrete and Bricklaying Begin
Hempcrete can only be found in a handful of buildings but it’s only a matter of time before this insulation technique spreads. Hempcrete is a mixture of lime, water and hemp shives (core of the stem) packed into the wall cavities boarded with plywood forms that leap frog upward, similarly to the slip straw walls we have already completed, as you finish a layer. Also like the slip straw, this will take at least a few weeks to dry before it can be plastered. We were hoping that the mixer that was bought for the course would be ideal for mixing the hempcrete but it wasn’t to be. The mix we were looking for was heavy on the hemp so that the curing time is as quick as possible without compromising the structural integrity or insulating qualities of the finished product. This meant that we could only mix in about half the hemp we wanted in the mixer or else a big gooey mess resulted. After adding in the second half of the hemp into the first couple of batches by hand, a member of the crew known for his staggering genius suggested using the tiller we had on site to break up the hard clay used in the slip and plaster to incorporate the remaining hemp into the mix. Thankfully it worked very well, much to the delight of all that had toiled away mixing the first two batches by hand.
Something we neglected to add to the journal in the weeks leading up the break was all the hard work happening on green roof. There was plenty to do laying the waterproofing membrane, border lip, and layers of growing medium. In fact, one morning saw the entire course commandeered into a makeshift bucket brigade to send all that gravel and sand up to the roof via some scaffolding and many pairs of hands. We have a great professional working with us, who also happens to be an alumni of the course, to get this done right. It will be very exciting to see the native plant species that will be planted up there hopefully thriving next season.
One other big job that began this first week back from our reading week was laying the brick wall that separates the foyer from the main hall section of the building. Using reclaimed brick from the area, a few lucky students along with Kevin Dunfield of Dunfield Masonry, began putting together what will be a focal point of the interior. The wall contains two arched openings and so far looks like it will be spectacular. In addition to this brick section, the interior walls team also added the wooden framing that will enclose the office and mechanical room, and the metal studs that will divide the two bathrooms and food preparation/arts and crafts area.
As the time begins to melt away quickly, it was also nice to see some painting going on as well as much preparation for the shingles to start to be installed next week. Things are really coming together nicely on site and as always we encourage everyone to stop by and check our progress on Tuesdays between 5:30 and 6:30.