By Heather Jones Source: dailybusinessbuzz.ca The first hempcrete building in Atlantic Canada will be constructed this summer at the Dorje Denma Ling program centre near Tatamagouche, Nova Scotia. “Hemp-lime masonry, or ‘hempcrete’, is a cutting-edge natural building material,” Dorje Denma Ling Sustainability Manager Dominic Watson Wall explains. “It is attractive, has great thermal and acoustic insulation properties and is carbon-negative, with no toxic elements, while being affordable and extraordinarily simple to build with.” Wall says hempcrete “can be used to build walls or as an in-fill for roofs, floors or as a plaster. It uses industrial hemp, a crop already widely grown in Canada and renowned as fiber, food, and biomass.” Hempcrete is a bio-composite made up of the hemp plant’s woody inner core (shive or shiv) and a lime-based binder. There is high silica content in the shive, according to American Lime Technology (ALT). Its website says hempcrete is “a lightweight cementitious insulating material weighing about a seventh or an eighth of the weight of concrete.” ALT’s website also notes that weather conditions at the jobsite can effect drying so the company has a factory that can dry hempcrete panels off-site. Hempcrete Australia Pty Ltd.’s website claims that the product prevents mould growth, is fire and termite resistant, and that its hard wall surface is vapour permeable— preventing condensation and reducing humidity. Wikipedia says the usual compressive strength of hempcrete is about 1 MPa, about 1/20 of residential grade concrete. The encyclopedia says hempcrete’s density is 15% of traditional concrete, as well as carbon negative… “Like other plant products, the hemp crop absorbs CO2 gas as it grows, retaining the carbon and releasing the oxygen. 165 kg of carbon can be theoretically absorbed and locked up by 1 m3 of hempcrete wall over many decades.” Dominic Watson Wall says, “Hemp-lime slurry is cast into walls using forms, then the walls are plastered. This method does not require the use of a significant amount of energy, it is easy, cheap, and results in a permanent wall as beautiful as adobe in appearance. No Portland cement is needed in hempcrete. And you cannot get high from the industrial hemp plant, if anyone asks.” Steve Allin will teach the Building With Hemp a Hemp:- a Lime Masonry Workshop July 22-25 in Tatamagouche. The author of Building with Hemp 2005/1013, Allin has constructed numerous hemp buildings over the last 16 years. He lives in the south west of Ireland, from where he works internationally as a hemp building consultant and teacher. At the Tatamagouche workshop “participants will learn both the theory and practice of using hemp-lime masonry in green buildings,” Wall says. “This workshop is appropriate for individuals interested in green building as well as professionals looking to broaden their expertise. In addition to direct instruction and technical information, there will be invaluable hands-on experience by actually using the material in building with hempcrete.” For workshop program information or to register, contact: http://dorjedenmaling.org/program-details/?id=137636