This week the Endeavour class spent a day at the facilities of NatureBuilt Wall Systems, where we assisted with the construction of some of the S-SIP walls that will be used in Canada’s Greenest Home.

The S-SIPs are largely identical to the load-bearing straw bale walls that have been used since the first straw bale buildings were constructed in the late 1800s. But rather than building them by stacking bales vertically and plastering in several coats, they are built in a shop space and plastered while lying horizontally. This greatly reduces the amount of labour time involved and ensures walls of consistent strength and size.

We have chosen to use the S-SIPs because they meet so many of the criteria we have for Canada’s Greenest Home:

• Locally harvested materials
• Renewable materials
• Reproducible technology
• High energy efficiency
• Low embodied energy
• No off gassing or toxins
• Affordable

Many straw bale buildings use an extensive wooden framework to create a structure to support a roof so the straw bale and plastering work can be done under protection from weather. The Bio-SIPs use the simplicity and low lumber count of load-bearing walls without the need for excessive wooden framing, capturing the benefits of the load-bearing capacity of straw bale walls.

NatureBuilt takes environmental responsibility seriously, right down to the use of used fryer oil as a release agent in their forms. It was great to be in a workplace where our ethics at Endeavour are so closely matched.

The class got to experience the entire construction process for the panels, including assembling and leveling the wooden frames, selecting and sizing bales, mixing and placing plaster and assembling the bales in the frames. In one short working day, we were able to help build nine of the 24 panels for our project.

The walls will be delivered to our construction site when the first floor framing is ready to receive them.