What’s good for the planet is good for you too!
More and more people are waking up to the understanding that the choice of materials we build from has a huge impact on the health and comfort of the occupants. Since the 1950s the construction industry in the UK has increasingly used highly processed, synthetic and chemical-based or -treated building materials. This has resulted in a large number homes which are prone to cold and damp, and contain harmful levels of toxic chemicals that are at risk of “off-gassing” into the interior of the building.
This has led to situation today where doctors are prescribing home insulation as the effects of cold and damp in homes is costing the NHS £2.5 billion a year, and recent studies have shown that even in our polluted cities the level of toxins inside our homes is often greater than that in the outside air.
For those wishing to create warm, healthy, chemical-free indoor environments, hempcrete has a range of benefits, namely:
It is “breathable” (vapour permeable) and hygroscopic: hempcrete walls and the lime or clay plaster finishes will passively “buffer” the levels of humidity inside the home, absorbing moisture from the air into the wall during times of high relative humidity and releasing it again when humidity levels drop. This eliminates condensation on the surface of the wall, preventing the conditions for damp spores to grow, and keeps internal humidity levels within the 40-60% range which inhibits the growth of viruses and bacteria. All of this is achieved without the need for mechanical ventilation systems.
Because of the lime binder which coats every particle of hemp in the hempcrete mixture, hempcrete achieves good ratings for fire-, rot-, and pest-resistance, without the need for additional treatment with potentially harmful chemicals. The fact that the structural frame is set within the hempcrete wall allows for untreated softwood to be used, further reducing the need for chemicals in the home.
Staying warm (and cool) without costing the earth
The extraordinary thermal performance of hempcrete – brought about by the combination of insulation and thermal mass (heat store) within the same material – means that the interior of hempcrete buildings remains at a near constant temperature with little demand on heating or cooling systems. Warm in winter and cool in summer, hempcrete homes are comfortable and healthy to live in, and help to reduce the financial impact of fuel bits on their occupants.