Baling-on-the-Edge is our original straw-bale building system in which straw bales are stacked on-edge in a running bond and fastened to external pins on only one face of the straw bales. The advantages of this system compared to straw-bale building systems in which straw bales are laid flat are the following:
- less straw bales — straw bales stacked on-edge are taller than straw bales laid flat
- more floor area — straw bales stacked on-edge are thinner than straw bales laid flat
- same insulation value — straw bales stacked on-edge with the straw stems aligned vertically have the same R-value as straw bales laid flat with the straw stems aligned horizontally
- stiffer wall — external pinning is structurally superior to internal pinning
- no condensation potential — internal pinning (steel rebar) can provide a location for water vapor condensation within the straw-bale wall, eventually leading to rot
- less pins — straw bales stacked on-edge require only one set of pins (single face of the straw-bale wall) whereas straw bales laid flat require two sets of pins (interior and exterior faces of the straw-bale wall)
- no trimming — straw bales stacked on-edge have relatively smooth and uniform faces for plastering whereas straw bales laid flat require some trimming prior to plastering
- same ease of plastering — plaster adheres equally well to straw-bales stacked on-edge as to straw bales laid flat
Once the straw bales have been stacked, both the interior and exterior faces of the straw-bale walls are coated with a thick layer of earth plaster. This earth plaster is the key to success of the system — the desiccant properties of clay result in the earth plaster wicking moisture out of the straw bales, evaporating it to the atmosphere. A thin coat of breathable finish plaster is then applied over the rough coat of earth plaster. Lime plasters are typically selected for exterior surfaces because of their weather resistance; the choice for interior finish plaster is usually based on aesthetics — lime, earth, and gypsum plasters are all appropriate. It should be noted that concrete stuccos are detrimental to straw-bale walls, and therefore are never recommended.
We have optimized the Baling-on-the-Edge straw-bale wall system for several structural framing options, including timber frames (frame fully exposed) and post-and-beam framing (framing members hidden). We have also developed extensive construction details for foundation and roof interfaces, door and window framing, electrical and plumbing integration, cabinetry and trim attachment, etc. Please contact us for specifics regarding your natural building project.
Our Edge-Plus straw-bale building system is a variation of our Baling-on-the-Edge system, optimized for structural stud framing. This revolutionary new innovation boosts the insulation value of the entire wall assembly sufficiently to meet Passive House standards, allowing elimination of the conventional heating/cooling system. Why settle for just the benefits of straw-bale construction alone, when you can get these benefits "PLUS" those of Passive House energy performance — through Edge-Plus!