A field of cannabis plants will be grown in East Lothian to support a new generation of building materials that are being made in Scotland from hemp.
Edinburgh-based firm Industrial Nature is to bring a new low-carbon, sustainable building material to the market next year.
Made from industrial hemp fibres and a complex compound of minerals, IndiBloc is naturally insulating and stores heat with claims the building material can significantly reduce heating bills.
Scott Simpson, co-founder of the firm, said the field will be planted next year with production of IndiBloc due to get underway in Leith in April.
Mr Simpson said: “IndiBloc is not just a eco-material - it has some amazing performance properties.
“At the moment we are getting our hemp from the north of England but we have a farmer on board in East Lothian who will grow a pilot field for us.
“After the high-value fibres are removed for textiles, we take the left over materials.”
Hemp has a long tradition of industrial use. During the reign of Henry VIII, it was compulsory to grow a quarter acre of hemp for every 60 acres under cultivation.
Cultivation was outlawed in the UK in 1928 with industrial hemp made legal in 1994.
A Home Office licence will be required for the East Lothian planting.
Mr Simpson added: “The plants are the same as the cannabis sativa plant but without the bud.
“You would have to smoke a telephone pole-sized joint to get high on it. It is completely legal to grow.”
Mr Simpson was first inspired to improve building materials after working in community development in Scotland.
He added: “There were a lot of people living in Dickensian accommodation. They couldn’t afford to heat these houses, they were damp and mouldy.”
His interest in low-carbon, healthy, building materials was then forged on a masters in sustainable architecture.
Mr Simpson said: “The blocks insulate better that existing systems. We are essentially replacing foam insulation and concrete with an insulating block which stores heat.
“Ultimately, they save you money heating your home.”
He claimed building a house from the blocks, which are usually placed around a timber frame, had potential to save £11,000 in heating costs over 50 years.
Mr Simpson added: “I’ve used hemp bio-composites in my home – we paid £270 for our gas bill for our 3 bed home last year. And we keep the windows upstairs open 24 hours a day – even through winter.
“I go to bed at night at 20 degrees, and I wake up and it is 20 degrees. Almost no heating – most heating is passive, from cooking, the sun, or from neighbours.”
The blocks are also vapour permeable, which stops a build up of moisture and mould.
“The buildings are breathable - they are healthy buildings,” he added.
The creation of IndiBloc comes following the success of Hempcrete, a mix of hemp and lime, which has been used in buildings such as the archive store at the Science Museum archive stores.
Here, heating, cooling, and humidity control was achieved without the need for mechanical systems.
Buildings account for 50 per cent of the world’s carbon emissions when the manufacture of materials, construction, operation and heat loss are taken into account.
Mr Simpson, who has received “outstanding” support from the Edinburgh Centre for Carbon Innovation and Zero Waste Scotland, said IndiBloc was carbon negative given the material locked in more carbon than was used to make it.
He added: “If you were to take all the new homes made in the UK last year - around 143,000 - and built them with IndiBloc, that would save the equivalent of 9.3m tonnes of carbon dioxide.
“That is around one-fifth of Scotland’s annual emissions.”
He and his three colleagues have collected a series of awards for their low-carbon and environmental work.
They include The Best Circular Economy Initiative from Scottish Resource Awards.
The company was also named first Place winners in Scotland’s Climate Launchpad 2017, a European-wide competition for low carbon entrepreneurs.
Later this month they will learn if they have won in three categories at the VIBES Scottish Environmental Business Awards.
Mr Simpson said Scotland had been “fantastic” in supporting low-carbon targets but added that policies were needed to support the use of sustainable building materials
He added: “It’s good to have carbon reduction policies which drive energy efficiency as this means certain insulation standards must be met.
“But there’s nothing that says what sort of materials should be used so petrochemical foam insulations are used: materials which are toxic, have high embodied carbon and end up in landfill.
“The Continent is really miles ahead us on this. We want to build on an industrial scale but we need the support to do that.”