Hempcrete

Hempcrete is a bio-composite made of the inner woody core of the hemp plant Cannabis Sativa L. mixed with a lime-based binder. The hemp core or “Shiv” has a high silica content which allows it to bind well with lime. This property is unique to hemp among all natural fibers. The result is a lightweight insulating material ideal for most climates as it combines insulation and thermal mass.

Like other plant products, hemp absorbs CO2 from the atmosphere as it grows. Furthermore the carbonization lime during curing adds up to this effect as lime turns to limestone, a process that may last 100 years. Hempcrete is a renewable, non-toxic and breathable material that produces a comfortable and healthy indoor living environment with high indoor quality. It is a low density material (around 1/7th the weight of concrete) and resistant to crack under movement thus making it highly suitable for use in earthquake prone areas.

The concrete industry is responsible for a large amount of CO2 emissions worldwide. Global CO2 emissions from cement production represent 4.5% of global CO2 releases from fossil-fuel burning. Other disadvantages include phenomena such as surface runoff, the urban heat island effect, generation of concrete dust and emission of toxic and radioactive substances. These hazards only make the need for more ecological and human friendly construction greater.

Hempcrete is one of the best performing, non-toxic, ecological and renewable materials available. It has a negative CO2 footprint thus alleviating the Greenhouse effect. It improves air quality, energy consumption for heating and cooling providing a comfortable and healthy living environment. Cool in summer and warm in winter.

Χαρακτηριστικά

Density	260-400 kg/m3
λ Value(mK)	0.06-0.09 (m/K)
U Value 300mm wall thickness	0,23
Fire resistance	~1 hr / 10 cm wall
CO2 Enchain	110-165 kg/1 ton
Hygroscopicity	3.4 x 10-5 PSI

Naturally termite, pest and mould resistant
Durable (weather-resistant)
Solid mass construction giving good air tightness (no heat or cool lost through air gaps)
Hygroscopic thereby buffering fluctuating temperature and humidity
Negative carbon footprint (~100kg of CO2 lockup per cubic meter used)
Fully recyclable and reusable without huge energy requirements to break it down

Hempcrete is the new ally, along with other natural materials like straw, clay, wood and stone, in constructing buildings that last for generation, reinventing the meaning of ‘construction’ (Οικο-δομή in Greek, which translates to "Ecological Building".

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