The Australian Hemp Masonry Company

No Frame
No Frame

Hemp Lime BuildingThe most common form of Hemp wall construction involves tamping or placing the hemp and binder blend into shutters (formwork) which are supported off a conventional timber frame. Benefits include:Excellent thermal insulation characteristicsExcellent acoustic isolation Carbon positive building material, absorbs CO2 from the atmosphere both during the plant growth phase and again as the material gains strength and matures. (100sq m with 300mm thick walls) will lock up 7.9T of CO2 in the walls. Estimated rate of carbon sequestration is 165Kg CO2 capture/m2. When regionally farmed hemp is used, a highly sustainable and affordable housing material is created from a readily renewable resource. Hemp houses can be very effective carbon sinks as a 300 year old Japanese Heritage Trust Dwelling at Miasa Mura demonstrates. The material is highly durable where walls are protected from constant moisture. Breathable walls provide excellent indoor air quality and moulds are avoided.Demolished hemp masonry walls can be readily reused in new constructionSimplicity and ease of construction.Hemp lime building materials are fire retardant and rodent resistant.Energy and thermal performance (Results from independent research at the Building Research Establishment (BRE) UK).The beneficial balance between thermal mass and thermal inertia means that the internal temperature is very effectively insulated from the external environment. Haverhill Housing Project showed hemp houses were more thermally efficient than conventional masonry. Tests of the thermal conductivity of walls by Plymouth University led to an agreed reading of 0.08w/mK. These were taken on a 200mm thick wall that had been constructed a number of years earlier. The "R" value (thermal resistance) is 2.75 with plaster and surface resistances taken into account. "U" value derived from this would be in the region of 0.36 -0.37W/m2K. This empirical work confirmed a lambda value of 0.08 - 0.09 for hemp and lime and as this conservative figure has been confirmed by so many authorities that it seems to accept this when making building regulation applicatons. (Bevan and Woolley, 2008)Acoustic separation provided by hemp masonry construction compares favourably to conventional masonry. Embodied energy for hempcrete construction is 1.15kw/cm - significantly less than most other forms of wall construction. No kiln baking required. Australian ResearchAHMC Binder and Render meet the Standards of the Building Code of Australia. All documentation is provided to clients.The goal of the research at UNSW was to develop an Australian binder that could be used in mainstream hemp lime construction in the absence of hydraulic lime, which forms the basis of the binder used in the European hemp construction industry. Australia does not produce hydraulic lime and the transport of materials from Europe has a high carbon footprint. Working with local resources was the starting point. Goals of the research:Maximising the amount of hemp in the building material as it is the renewable resource. (More than 60% of the building material is hemp).Developing a mix suitable for commercial building while minimising the addition of cementitious materials and avoiding highly toxic additives. Using local resources : Although hydrated lime production has a substantial carbon footprint, it is significantly less energy intensive than cement or hydraulic lime. European lime based binders can have up to 50% cement content. Some use just hemp and cement. The higher the cement content, the less recyclable the product. We use local sand in the building material to reduce energy costs associated with drying, bagging and transporting sand and to minimise mined materials. It gives early stability Affordability - Research at UNSW focused on trialling both hemp hurd (the inside pithy fibre) and whole stem hemp chopped at varying lengths, once the high costs of hemp decortication (or separation) were identified. The research also focused on developing a commercially competitive building process.Australian hemp, Australian hemp builder, building with Australian hemp lime, hemp shelters, hempcrete, hemcrete, build with hemp, hemp building, hemp housing, hemp houses, retrofitting with hemp, hemp lime construction, hemp lime building materials, kender haz, hemp homes, hemp building materials, hemp lime render, hemp renders, rendering with hemp lime, breathable building materials, sustainable building, ecobuilding, eco-houseshealthy housing, hemp lime pole costruction, hemp floors, hemp ceiling insulation

building a sustainable future

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