General Physical characteristic and Installation of In Verto AgBag
The AgBag provides a durable inexpensive growing structure to facilitate participatory research and to experiment with vegetation based systems design. The platform features a nondestructive, safe but temporary counterbalanced attachment to railings and windows. It can be easily installed on existing structures by an individual with no particular tools or skills, and easily integrated into diverse building situations that allow counter balancing.
The high tensile spun olefin (HDPE) material is antimicrobial; fire retardant and provides a puncture-resistant waterproof membrane well known in the construction industry and complaint with existing regulation and code. It is biodegradable and recyclable, yet the UV stabilized material can be used for long-term (decades-long) outdoor installation. Unlike window boxes, blow-molded thermoplastics for green walls or other planting structures, the counter balanced soft structure has no catastrophic failure mode, for example detaching and falling on someone. The distributed compressive loading is typically not a significant additional structural load.
Tyvek has been exploited in sail making for the burst tensile performance and uses similar sewn construction as used in the AgBag. The nonwoven material has many similar properties to felts from natural fibers, providing a moisture barrier with high breathability. Tyvek is more waterproof that synthetic/natural felts. Natural fibers will eventually wet (after approximately 2hrs of submersion) and then cease to provide water barrier. In the AgBag design the moisture retention property is exploited to minimize water loss from exposed soil surfaces.
However, because air can pass thru this membrane, the soil remains well oxygenated and promoting health rootzone biodiversity and growth. This also prevents slime molds on the inside or outside. The micro porous breathability is a mechanical property of the felted nonwoven fiber alignment of the single (HDPE) material process. The fabrication process involves a heat binding process and no additional binders are used in the making of the Tyvek material. Hence, there is no off gassing for indoor applications.