Hemp 101 for Construction A Sustainable Finishing Material HELLO,
Welcome to Hemp 101 for Construction: An introduction to one of the oldest and "newest" building materials on earth.
For professionals in construction who are new to hemp...
This is not a technical guide, it's an overview of a high performance, versatile, and resilient natural material that's going to flood the market in the coming years.
We'll take a short look back at hemp's history, dive into technical and functional uses, then look forward to how it can help us collectively move towards a more sustainable earth.
Through the lens of your professions, you can view this material from many perspectives, recognize its limitations and potential, as well as evaluate both short term benefits and long term returns.
I created this guide because the reemergence of hemp is recent, and so naturally, many people have never heard of the plant, or think hemp is Marijuana. Education on the facts and science is our path to breaking the stigma, and to adding one of the strongest fibers on earth to our toolbox. I invite you to explore it, and consider it on your next project.
Hebah Saddique, PMP Founder, Green Takeover
October 2020 1 GREEN TAKEOVER Born to bridge the worlds of climate action and industrial hemp, Green Takeover symbolizes the union of these two movements.
Our mission is to inspire action using hemp as a catalyst for a green economy.
Hemp fits directly into conversations of a circular economy, regenerative design thinking and materials for a closed loop. It fits into the blueprints of green cities. It fits, accelerates, and enhances solutions addressing 1/3 of the United Nations Sustainable Development Goals that relate to a green economy.
Green Takeover is a hemp-focused sustainability, project, and management consultancy. Helping clients strengthen their connection between strategy and operations, partnering with them to implement bold radical initiatives, and working with them to adopt best-in-class sustainability strategies.
We're personally invested in a booming hemp industry. Growing hemp plays a vital role in cleaning our soil, absorbing enormous amounts of carbon from our atmosphere, reducing our footprint, and enhancing our collective climate action efforts.
Hemp is good for people, profits, and our planet. We encourage you to explore it, grow it, and use it, because in the end, we're all in this together.
October 2020 2 ACKNOWLEDGEMENTS
Green Takeover would like to gratefully acknowledge and thank the companies, and people behind them, that created and published informative content that served as our sources for this booklet.
Thank you for pioneering the hemp building industry, for sharing your knowledge and learnings, and for contributing to our better understanding of the technical applications of hemp’s uses and benefits as an environmentally friendly building and finishing material.
We would particularly like to thank
American Hemp LLC House Planning Help Podcast American Lime Technology Just Bio Fiber AzoBuild Khaled Labidi Build With Rise Kyla 'Hempress' Hill Designing Building Lancaster Farming Goodvin Designs Left Hand Hemp Green Building Advisor Ministry of Hemp Green Building Canada National Hemp Association Hemp Foundation Pip Magazine Hemp Industry Association Pro Trader Craft Hemp Monster The Hemp Entrepreneur Hemp Technologies Global The Hemp Company Hempcrete Australia The Hemp Mag Hempcrete Direct UK Hempcrete HempME Woodworking Network
October 2020 3 Content
1 WHAT IS HEMP? 2 HEMP BUILDING MATERIALS 3 MAKING HEMPCRETE 4 BENEFITS OF HEMP 5 CONSTRUCTION INDUSTRY 6 GREEN CITIES 7 MONEY TALK 8 CLIMATE ACTION 9 RESEARCH 10 RESOURCES
4 WHAT IS HEMP? LEGALLY Hemp is Cannabis Sativa containing SCIENTIFICALLY less than .3% of the psychoactive compound Tetrahydrocannabinol Belongs to the plant Family (THC) Cannabaceae. The Family is grouped in 11 genera, one of them is the Cannabis COMMERCIALLY genus. There are 3 different types of A versatile mega resource that can Cannabis species that each have be made into tens of thousands of different properties. Sativa, Indica, and products. Used for centuries to make Ruderalis. Industrial hemp is a textiles, ropes, , biofuel, building Cannabis sativa. materials, foods, medications, HISTORICALLY papers, and bioplastics. A layer to be integrated into most industries, just From 1000 B.C. to the 1800s AD, hemp like the .com boom. was the world's largest agricultural crop. Production diminished during ENVIRONMENTALLY the industrial revolution as substitutes A renewable, high yield, agricultural became accessible and the product. Can be made into a petrochemical age began. In the 1920s plethora of biodegradable industrial giant corporations, fearing hemp’s materials. It’s a carbon sink that can resurgence as a big threat to their also help tackle plastic pollution, businesses, proposed prohibitive tax deforestation, soil erosion, fossil laws, passing the Marijuana Tax Act in fuels, and much more 1937, and labeled it a narcotic in 1970. ECONOMICALLY SOCIALLY An abundant renewable resource Commonly confused with its cousin, that’s competitive in pricing, Marijuana. Hemp started to fade from performance, and environmental mainstream language early 1900s. By impact. Due to its accessibility, short the 1930s propaganda campaigns harvesting cycle, and rising global emerged popularizing the term demand for sustainable materials, “Marijuana” for the Cannabis species, growing hemp can give every farmer and linking it to evil. a cash crop, and offer a scalable resource to build a green economy.
October 2020 5 ANATOMY & USES OF A HEMP PLANT
1 ROOTS
Used for centuries as a topical remedy for bone and muscle aches. Boiled hemp roots help reduce joint stiffness and inflammation.
The stalk of the plant is split into fibers and hemp hurd
2 STALK - FIBERS 3 STALK - HURD We can make fabrics, Hemp hurd is similar to industrial textiles, paper wood chips, from it we make products, insulation, etc. hempcrete building Think of anything you know materials, or we can grind that’s made of fabric or paper, the hurd and use it as a base it can be made of hemp. to make bioplastic.
4 LEAVES
Make quality animal bedding because its absorbent. Also used as mulch and compost.
5 FLOWER
Extract cannabidiol (CBD) to produce medications such as those for epilepsy, joint pain, and fibromyalgia to name a few, as well as to make health supplements. Most abundant in the flower but also in the stems, and leaves
6 SEEDS
A generous source of protein, essential fatty acids, and nutrients. Pressing the seeds we can make cooking oil, or we can produce biofuel or manufacture Industrial coatings and oil paints.
October 2020 6 ASSORTING THE MANILA HEMP FIBER IN A ROPE FACTORY MANILA, PHILIPPINE ISLANDS, EARLY 20TH CENTURY
Source: John Tewell, H.C. White Company
October 2020 7 A BRIEF HISTORY OF 2200 BC Hemp was grown throughout HEMP China for its seeds & fiber.
500 AD Mortar hemp bridge built in Gaul (France today)
793 AD Vikings relied on hemp to supply their ships with rope, fish nets, and 1452 AD sail cloths 80 tons of hemp helped bring Columbus's ships to America 1619 AD and until the 1800s you could pay taxes with hemp! 1820s 80% of all textiles and fabrics for linen, drapes, clothing, bed sheets, text books, etc. are made from hemp fibers 1830s The cotton gin (invented by Eli Whitney in 1790) makes cotton a cheaper fiber than hemp 1920s The age of giant corporations begins in the Roaring 20s, and with it a wave of mergers, consolidations, and 1937 specialization across industries Marijuana Tax Act passes, placing a severe tax on cannabis. It is still legal to grow, though not without financial 1942 hardship Henry Ford builds a car using a blend of natural fibers including hemp Controlled Substances Act passes, criminalizing cannabis. First time in US Farm Bill passes removing 1970 US history hemp is considered an cannabis with less than 0.3% THC illegal drug from Schedule I controlled substances 2018
October 2020 8 BUILDING WITH HEMP
The woody inner fibers of the hemp plant (hemp Shiv or hurd) are used as a light weight biocomposite building material with a range of performance and environmental benefits. It's a resilient and breathable, low on toxins, long lasting and recyclable material that combines a variety of properties making it appealing to build with.
Hemp Insulation A durable, low-carbon, sustainable insulator. It'll keep buildings warm in the winter and cool in the summer due its high thermal mass and low conductivity. Available in insulation blankets or boards, and can be used for insulating roofing, floors, and even drywall.
Natural Insulations Hempcrete Used to build non-weight bearing infill walls. Architects love hempcrete for its design flexibility and performance benefits. Builders for low maintenance requirements. Hempcrete is not a structural element so it's not a direct substitute for concrete. Left Hand Hemp
Hemp is an environmentally superior material because it is a carbon sink. It's take in 2 times as much Carbon as mature trees in a comparable area. Plus, it takes very little energy to grow and process into insulation. It’s recyclable at the end of its useful life and can be repurposed and made into paper products or a biofuel.
October 2020 9 HEMP INSULATION
Hemp is a prime insulation material that can help building owners save money on energy, and provide a healthier space.
It's a low carbon & durable alternative to fiberglass.
Its low thermal conductivity ( 0.039 W/m°K) allows it to not only retain heat but also regulate thermal performance for an optimum indoor environment. Due to the high silica content of hemp it makes for very energy-efficient buildings because it has the ability to store warmth and give it back after a while.
Hemp is vapor permeable so moisture moves right through it. As opposed to plastic foam, or fiberglass which has to be used with plastic-sealed batts - otherwise there is no vapor barrier. Fiberglass isn’t the healthiest option either - it uses formaldehyde as a binder, which can leak out in the air and if slivers of fiberglass are inhaled can cause lung disease.
It’s mold resistant due to its ability to absorb and release water, and It’s also resistant to the attack of the insects.It can be bought either in rolls or panels and does not require skilled work for its laying.
Green Building Advisors Material District
October 2020 10 HEMPCRETE
Hemp hurds + Water + Lime binder = Hempcrete
Hemp hurd. Woody inner core of the hemp's stalk. Usually comes ground up and pretty uniform in size. Through a retting process the ligaments in the stalk start to break down, so the fibers can be separated from the woody core - shiv- hemp hurd. Hurd is 50 to 70% cellulose. When buying hurd you want it between 1/2" to 1" in length (1.27cm - 2.54 cm) plus, you don't want it to have a lot of dust because it will mess up the ratios. Left Hand Hemp
Lime binder. Type and grade of lime, along with the mix ratio of the binder itself, are key variables that determine strength and durability of hempcrete. The binder component in hempcrete, unlike other construction composites (such as concrete, mortar, and plaster), is not intended to fill all the voids between the hemp particles, but rather to cover the particles and allow them to stick to each other.
Water. Hemp hurd is porous and can absorb a lot more water than is needed to make quality hempcrete, so controlling water quantities is critical. Too much water will make it much denser, and can significantly extend drying time as well as affect the binding reaction with the hurd.
October 2020 11 Making & Building with Hempcrete
Typical ratio M I X R A T I O S V A R Y B A S E D O N C L I M A T E I N A R E G I O N , A N D O N T H E 4 P A R T S H U R D I N T E N D E D U S E . U S I N G A L I G H T M I X F O R R O O F I N G , A N D A H I G H E R 1 P A R T B I N D E R D E N S I T Y A S W E G O D O W N , T O A 1 P A R T W A T E R H E A V Y M I X F O R T H E S U B F L O O R .
#1 Add hemp #2 Mix water and hurd to mortar binder together mixer
Enough so that you can pack #3 Introduce the it into a ball yet fragile hemp and mix until enough to easily break it is coated
#4 Form it into the wall of a building. Hempcrete #5 Over time the chemical walls must be used reactions between the together with a load- water, lime and Hemp bearing frame of petrify the hemp and turn another material the lime back into concrete- like material that is light and strong
October 2020 12 Highland 3,000 sq. ft Hemp House Bellingham, Washington, USA After the hempcrete is cast, before the plaster is added.
Source: Tommy Gibbons Tommygibbons46 / CC BY-SA (https://creativecommons.org/licenses/by-sa/4.0)
October 2020 13 Concrete vs Wood vs Hemp
Compared based on 12 inch (300 mm) thick walls. Values vary based on environment, architectural design, civil * engineering and construction practices, plus a range of other factors.
F E A T U R E S C O N C R E T E W O O D H E M P
Compressive 2500 - 5000 - 73 - 508 Strength 5000 PSI 9000 PSI PSI
8 soft R-value 7.3 25 4 hard
Less Acoustic Sound Proofing Not great effective deadening Light & 3 times more Rigid & prone performs well resistant than Stability to cracking in earthquakes concrete Not prone, Susceptable Mold but it grows Anti fungal and to mold in and on it anti microbial
Source of air Demolition Biodegradable Biodegradable pollution
October 2020 14 P E R F O R M A N C E Benefits of Hemp
Y I E L D
1,500 square-foot house G E O G R A P H I C requires approximately F L E X I B I L I T Y 300 of 33-pound bags of hemp hurd. Grows in a wide range of climates. Depending on the geography and climate of an area, the thickness of hempcrete needs to be adjusted.
V A P O R P E R M E A B L E
As a hygroscopic material, M O L D & M I L D E W hempcrete is a breathable R E S I S T A N T and allows water vapor to pass through it. Unlike Great moisture control. Hurd is fiberglass insulation or a natural anti fungal and anti drywall. microbial material. Hemp fibers can take in twice its weight in moisture without impacting its performance. P E S T & R O D E N T R E S I S T A N T D E S I G N F L E X I B I T L I T Y Insect and rodent and termite resistant due to the lime binder Flexible to design and build in the mixture. with because it's ideal to use with other materials like stone, brick, or wood.
October 2020 15 T E C H N I C A L Benefits of Hemp
S T A B I L I T Y S O U N D P R O O F I N G Three times more resistant to Acoustic deadening due cracking than concrete. to porous nature of fibers. Hempcrete also helps keep framing studs well supported under load and movement.
T H E R M A L R E S I S T A N C E F L A M E R E S I S T A N T Cellular structure of hemp locks in a lot of air. So when Passed UK 70 minute burn test. mixed and compressed into In an experiment, after 8 a wall, it gives a material that minutes of holding a blowtorch has insulation and thermal directly to it, the fire only inertia. penetrated 1/2" from the surface
G A I N S S T R E N G T H O V E R T I M E C U R I N G T I M E
Gains strength over time with 6 weeks roughly to let the exposure to air. It's estimated to Hempcrete dry. Reduced to 3 - 4 absorb and sequester 25% - 35% if windows and doors are left out. of its weight in CO2 which causes Dependent on climate & season. the lime binder and hempcrete Maintains 8 - 9% of its moisture to petrify like a stone. content due it vapor permeability.
October 2020 16 A Home Made from Hemp that Will Blow your Mind
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October 2020 17 GLOBAL BUILDING INDUSTRY The construction industry is a huge consumer of natural resources, and a major contributor to climate change. Specifically, the cement industry is a primary producer of CO2 gases.
UN Environment Program studies show that the building industry contributes to 39% of global carbon dioxide emissions and 36% of global energy use.
Emissions are tied to construction practices, heating and cooling buildings, and lastly required maintenance once they are inhabited.
39% of global CO2 emissions
36% of global energy use
Poor building insulation is another cause of heat loss and higher energy consumption, impacting our carbon foot print. Walls are the highest contributors at 35% loss followed by 25% loss through the roof. According to a study, approximately 90% of US homes are under insulated.
Civil engineers and construction workers also face on-the-work health and safety hazards due to toxicity of certain materials, chemicals, and due to excessive emission of fugitive dust.
October 2020 18 GREEN SUSTAINABLE CITIES
With climate change front and center on global agendas, there’s rising pressure on the construction industry to curb its emissions and adopt eco friendly practices and materials.
Changes in what and how we build don’t only curb the causes of climate change, but also can better prepare us for its symptoms; such as floods and other environmental disasters.
Considering and prioritizing the green print and waste output of our buildings in final form, as well as in the ways we build it. "THE SUCCESS OR FAILURE OF CITIES AT ADDRESSING CLIMATE CHANGE ARE PIVOTAL IN OUR EFFORTS TO LIMIT GLOBAL WARMING. " IFC - World Bank Group
Hemp is a powerful material to evaluate. It has the potential to reverse the effects of global warming on a grand scale. Hemp is a carbon sink that absorbs more carbon per hectare than just about any other plant. The lime mixed with the hurd to make hempcrete also offsets the energy used to manufacture it by reabsorbing carbon dioxide from the atmosphere as it sets over time.
Design - using sustainable or recycled materials, designing with resilience to changing weather patterns in mind. Considering waste production and energy consumption needs.
Construction Practices - upgrade heavy equipment to newer, more efficient models or use alternative fuel sources when possible.
Building Operations - considering maintenance requirements, long term gains and returns vs short run savings.
Green Takeover offers training on the intersect of hemp and green cities, as well as consulting services to assist clients in detailing requirements, in planning, and in mapping out environmental impacts of their projects.
October 2020 19 E N V I R O N M E N T A L Benefits of Hemp
E N E R G Y E F F I C I E N T
Lime binder in hempcrete does A G R I C U L T U R E not need to be heated as much as conventional concrete Requires little to no pesticides, mixture, reducing energy costs. has deep roots so it rejuvenates the soil and can be grown asa. rotation crop. Absorbs toxins from the soil, used in phytoremediation C A R B O N S I N K
Hempcrete is carbon negative, so we're locking E N V I R O N M E N T A L up CO2 instead of emitting F O O T P R I N T it to the atmosphere. Every 1 sq. m wall of hempcrete Chemical free, non-toxic, locks up to 30 kilos of CO2 biodegradable material that can easily be recycled.
R E N E W A B L E R E S O U R C E
Hemp has a 6 month harvesting cycle. Trees take an entire P H O T O R E M E D I A T I O N generation. Deforestation is a Grows deep roots that can driver of climate change. pull out toxins. Used to clean soil from toxic and hazardous chemicals.
October 2020 20 This House Made of Cannabis Is Eco-Friendly and Beautiful
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October 2020 21 HEMP & THE UNITED NATIONS SUSTAINABLE DEVELOPMENT GOALS Hemp can positively impact 11 of the 17 United Nations Sustainable Development Goals.
Hemp can directly enhance and accelerate 8 of them, and can indirectly strengthen 3. It’s a biodegradable high performance industrial material, a high source of protein, a natural source of medication, and clean energy. Since we’re taking a construction lens, we will focus on Goal 9: Industries, Innovation, and Infrastructure.
Goal 9.1: Develop quality, reliable, sustainable and resilient infrastructure, including regional and transborder infrastructure, to support economic development and human well-being, with a focus on affordable and equitable access for all. Goal 9.4: By 2030, upgrade infrastructure and retrofit industries to make them sustainable, with increased resource-use efficiency and greater adoption of clean and environmentally sound technologies and industrial processes, with all countries taking action in accordance with their respective capabilities.
Hemp is a quality, reliable, sustainable, and resilient material to utilize in building global infrastructures. As a high yield material that can grow in a range of climates, hemp can become an affordable accessible solution to promote sustainable industrialization that is rooted in agriculture and agro-industries development. It’s versatility, performance capabilities, and environmental benefits make it a prime material to use for mitigation and impact reduction of our green print. Investing, and extending credit, to SMEs in hemp production and processing, advances a range of industries as it sits at the center of an economic ecosystem; grown locally being disbursed as raw material to various industries, while serving as a carbon sink. Investments in SDG 9 have a ripple effect and contribute to progress on other SDGs and their targets such as job creation, climate action, and sustainable livelihoods.
UN Deputy Secretary-General Amina Mohammed called SDG 9 a “docking station” for all 17 Goals.
October 2020 22 MONEY TALK IN 2020
MATERIALS In October 2020, Hempcrete materials cost roughly the same as traditional building materials. Mainly because since mid-April of 2020, lumber prices have risen by 130% (National Association of Home Builders). Naturally, shipping fees are a main part of the cost as well. As production, processing, and market supplies increase, prices will drop. EQUIPMENT A mortar mixer plus other equipment used on a typical construction site. Scaffolding, mixers, forms, misc. Hempcrete spray machines vary in size and strength, and can expedite the process of filling the frame molds. LABOR Hempcrete is labor intensive, especially if you don't have a spray machine. You'll need 5 - 6 people on the job. It's also a "new" field, so few have the experience or skills to build with it. Professionals with a construction background are easily able to pick up the required knowledge.
Typical timeframe for a standard home of 2500 sq. ft (232.25 sq. m) is 10 days. Factors affecting length of time are mixer capacity per day, plus weather conditions. Training workshops are emerging globally, and range from learning the fundamentals building a wall, to constructing a fully functional tiny home.
Green Takeover offers clients assistance in budgeting and planning project requirements and resources.
October 2020 23 Academic Research
Little evidence existed of cannabis programs, or reference to the plant, in U.S. higher education for the past 100 years. As laws eased between 2014 - 2018 Academic research and programs sprung up across global institutions. Majority focus on the Agricultural aspect.
Click for details
Undergraduate students in the Department of Civil Engineering test building material made of hemp byproduct.
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EPA funds student research promoting sustainability. Under supervision of the Department of Mechanical Engineering, their research includes evaluating construction materials made from hemp fibers.
Hemp-lime construction panels on test at University's new Building Research Park
"The 36 month program includes a 24 month test phase which will construct, instrument, Click for details monitor and analyze the environmental performance of a number of small experimental buildings."
October 2020 24 Click to visit their websites US UK HEmp Technologies Global Unyte Hemp Left Hand Hemp UK Hemprete HempStone Hempitecture Canada Hempcrete Natural Building HEMPCRETE CONSTRUCTION Belgium COMPANIES IsoHemp Natural Building AROUND THE WORLD
Australia france Hemp Homes Cavac Biomatériaux
India Sweden GoHemp AgroVentures Dalaro Hampa & Miljo AB
October 2020 25 BOOKS
The Hempcrete Book: HEMPCRETE Designing and Building with Hemp-Lime (Sustainable RESOURCES Building) By William Stanwix & Alex Sparrow.
Essential Hempcrete Construction: The Complete Step-by-Step Guide (Sustainable Building Essentials Series) Click to listen By Chris Magwood Click to purchase
PODCAST EPISODES 1. LANCASTER FARMING - JUST BIOFIBER QUESTIONS? HEMPCRETE BLOCKS. THOUGHTS? 2.MINISTRY OF HEMP - HEMPCRETE & IDEAS? SUSTAINABLE CONSTRUCTION 3.THE HEMP ENTREPRENEUR - #5 LIMEWORKS 4.THE HEMP ENTREPRENEUR - #16 HEMP HOUSE ON WHEELS EMAIL 5.& #26 KNOCK ON HEMP 6.HELEN EDWARDS - WHAT THE HECK IS [email protected] HEMPCRETE? 7.IRISH TECH NEWS - LEARN HOW TO USE HEMPCRETE IN CIRCULAR ECONOMY CONSTRUCTION 8. HOUSE PLANNING HELP - IS HEMP A GOOD MATERIAL FOR ECOLOGICAL BUILDINGS?
October 2020 26