News / “Largest Order of Hempcrete Blocks” used to build William’s Den

Designed by Native Architects of York, the William’s Den play barn, an adventure play complex, is opening this week, at Castle Farm, North Cave. Alex Sparrow of UK Hempcrete said “We are delighted to be working with Native Architects to provide a truly sustainable, low impact construction material for use in a building which will, in every sense, have a positive impact on future generations of children”.

The blocks, manufactured by Equilibrium, are an environmentally friendly building material, being insulating, breathable, and “better-than-zero-carbon” – the hemp contained in the blocks absorbs more atmospheric carbon dioxide as it grows than is emitted in making the blocks, including the manufacture of the lime ‘binder’.  This atmospheric CO2 is then locked up (‘sequestered’) for the lifetime of the building.

The hempcrete blocks, which are 300 mm thick, are being used in the ground floor walls of the building – a play barn – with a total area of 174 mof blocks being installed. Hempcrete blocks are formed from hemp ‘shiv’, the chopped woody stem of the industrial hemp plant, combined with a binder of natural hydraulic lime.

Hempcrete blocks, which come in range of sizes, are non-loadbearing but provide a natural, chemical-free, vapour-permeable, insulation material which also has thermal mass, giving it a uniquely effective thermal performance.

With a U-value of 0.23 W/m2K for the 300 mm block, or 0.17 for the 400 mm block, these blocks meet current building regulations with ease. However due to the thermal mass element ‘buffering’ internal temperature changes, hempcrete out-performs what is expected from its U value alone. In addition, with its ability to absorb and release water vapour, and allow it to pass through the fabric of the wall, hempcrete creates healthy, damp- and mould-free (and chemical-free) indoor environments.

You can find out more about William’s Den on their website and Facebook page: