The 11th Hemp Building Symposium: An Overview

BlogPress By Dermot Moore

Earlier this month, I joined a throng of enthusiasts, innovators and curious observers as they descended on Kanteen 25 in the northern outskirts of Amsterdam, Netherlands. One thing was on everyone’s mind at the 11th International Hemp Building Symposium: Industrial Hemp and, most importantly, how it alters the future of construction.

The Symposium

The lead organiser, Steve Allin, Director of the International Hemp Building Association (IHBA) and author of Hemp Building: 50 International Case Studies, ‘a comprehensive overview’, has been working ceaselessly with people across various disciplines and interests for many years.

This year’s event differs drastically from the first, back in 2009. The urgency to tackle climate disaster has kicked up several notches, and the stigma surrounding hemp is disappearing. Industrial hemp and other bio-material alternatives are gathering momentum and gaining international attention.


It was inspiring to see the work of Stephen Clarke of Heavengrown, who Zoom called in from Mexico. His presentation included the exploration of sugar cane and coconut in building projects—confirming and highlighting the importance of using local biobased materials. His work proved that hemp is simply an exceptionally resilient bio-material to work with.

I was eager to see Alex Sparrow, UK Hempcrete, as Hemspan shares the same goal of developing the local UK supply chain. Alex talked about his work with industrial hemp (APPG), which I looked into, and the impression I got was that the UK’s industrial hemp supply chain would truly bloom once there is a clear separation from drug-related laws. International building conglomerates, such as Kingspan, are pursuing hemp, becoming majority stakeholders in HempFlax Building Solutions GmbH, ‘previously part of HempFlax Group‘. This uptake is big news and should be a sign for governments maintaining old-fashioned laws.


The lively discussion sparked some debate, from climate change to carbon capture. The crowd seemed scrutinous of carbon technologies. Many questions were asked on this topic. But that is a good sign and highlights a trait of actual climate and human concern in industrial hemp circles: not wanting anything to go unchecked that might distract from ideal strategies. On climate change, Steve brought the question of its effect on crops to producers, and some expressed concern about increased droughts.

Demonstrations opened the door for questions on the scaling of hemp harvesting and factors that heavily influence the structure of hemp-lime mixtures. 

The HurdMaster MD1000Air, a micro-decorticator intended for small-scale hemp harvesting, was a huge draw for attention on the first day.

Working Together

US and European relations stood out, and attendees expressed eagerness to develop these ties. Jacob Waddell, founder of the US-based Hemp Building Institute, stressed the ‘need to show value’, relating specifically to the US market. Jacob was particularly passionate about hemp’s value to affordable housing projects, as many homes are built using substandard materials. A question this raised for me: How communicative is Europe’s hemp scene in expressing failures? We can learn from and avoid future setbacks when transcribing to a US context.

One thing made clear was the quality proponents of industrial hemp are striving for. This push for excellence starkly contrasts conventional construction, a champion of mass production for a cheap price. Experimentation with different hemp and binder mixes recorded by Joseph Little from TU Dublin and the role of hemp biochar for carbon capture and waste management, discussed by Nando Knodel of HempConnect, Germany, highlighted this drive for quality and sparked many questions. 

A need for clarity

Life Cycle Assessment (LCA): What is it?; What are the issues? How can they be managed? Hanfingenieur noted the necessity of making LCAs and other regulations easier to interpret and ensuring limitations, such as local climate and consideration that no specific person working with hemp and lime will create the same mixture, are made clear. An LCA also looks at carbon emissions, which is ideal if the goal is to produce as little carbon as possible in building construction.

80% of a building’s CO2 potential is spent before handing over the keys.


Take Away

The overarching impression I got from the 11th International Hemp Building Symposium is the need to address climate change through one of the largest polluting industries, construction. Others, such as Ashley Stallworth, Bio Fibre Industries, gave me their post-symposium impressions:

Unification through regional efforts bolstered by global leadership will help our industry fulfil its intent, which is to bring healthier materials into homes and buildings inclusively around the world, meaning for those who care to display safer, healthier community forums but most importantly for those who need them most in their homes; we have the opportunity to build better again.

Hemp is mainstream now. It is a question of developing clear and concise frameworks for building with this material. Enthusiasm for structural change in construction conventions is widespread.

Dermot Moore is our analyst at Hemspan®. If you have any thoughts or a topic that you think we may find of interest, please contact Dermot.

This article was also published in HEMPBUILD Magazine 20th October 2023


Voorst Town Hall - Hempcrete façade