Hemp is an ancient crop, grown for its fibre and put to thousands of uses. Unreasonably lumped in with cannabis, hemp was supplanted and restricted for nearly a hundred years – but it is now being heralded as an outstanding building material for our time.
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New Zealand’s first house made of hemp will be finished this summer. Lance and Miranda Palmer are building a 195 m2 home in Taranaki using hempcrete for their walls.
Why hemp? “I wanted a home that would breathe naturally,” explains Lance. “When we learnt about hemp, it ticked all the boxes. It’s unusual in that it’s both a great insulator and yet provides a lot of thermal mass.”
Benefits for building
Hemp as a building material delivers an impressive list of benefits, say proponents like Greg Flavall, a builder and entrepreneur encouraging the use of hemp in New Zealand. He claims hempcrete is a carbon neutral or even carbon negative material. The fast growing hemp sequesters carbon and, once processed, the fibres are mixed with a lime and cement binder to create ‘hempcrete’. The lime continues to harden over time, absorbing more carbon as it calcifies. Some 110 kg of carbon is locked up per cubic metre of hempcrete, according to UK consulting firm Hemp-Lime Construct.
Hemp building materials are lightweight, insulating, and highly breathable, producing homes with excellent air quality, according to Greg. It’s fireproof and rodent and insect resistant. It’s extremely durable, with an expected lifespan of several hundred years. Hemp is also versatile; just vary the ratio of binder to make floors, walls, or insulation. And it can be deconstructed and recycled in another building project!
What it isn’t, is load bearing: hempcrete is being used in New Zealand as infill between timber structural framing.
Eco-architect Graeme North also has an interest in hempcrete but takes a more cautious view. He questions the claim about carbon neutrality, saying that manufacturing lime produces more carbon than it subsequently absorbs. “Claims of both insulation and thermal mass need to be considered carefully,” he warns, as it depends on the thickness and density of the wall.
Hemp growing in Taranaki
Different varieties of industrial hemp are grown depending on the desired yield (seed, fibre or fabric). They are alike in having extremely low levels of tetrahydrocannabinol (THC), the active ingredient in the Cannabis sativa grown for marijuana use: 0.3% compared with 3–22%.
A regulatory scheme was established in 2006 that makes it legal for license holders to grow, process and distribute hemp in specific circumstances. A grower must send crop samples to a lab before harvesting, to ensure THC levels are below prescribed limits. Crops not meeting this requirement may be destroyed. As at 23 September 2013, 27 licences to grow industrial hemp have been issued by the Ministry of Health, with a further two being processed.
Last summer, two Taranaki farmers working with Greg Flavall got their hemp licenses and 4.45 ha was sown, including at Avonstour, an organic, rare breeds family farm east of Stratford.
From field to house
Hemp is a fast-growing and robust annual broadleaf, with a root system that can extend two metres. It is naturally insect and pest tolerant and may not require fertilising.
Hemp’s history spans some 12,000 years, having been grown in Asia and the Middle East for fibre to make fabric, cloth and rope. It was grown extensively in the US from the seventeenth century. But its cultivation was outlawed in the US and UK in the 1920s and 30s when fears about cannabis use were running high, and fell away in Europe last century as hemp was supplanted by newer, synthetic fibres.
After harvesting, the plant is retted: soaked in water to loosen the fibres from the woody core. The fibres are separated out in a mechanical process called decortication before the stem is dried and chopped to produce shiv. To make hempcrete, the shiv is mixed with a small amount of hydrated lime-rich binder. Greg advocates a 5:1 mix of lime and cement, which means the binder is about two percent of finished volume. Natural pigments can also be added to create striking natural colours or patterns.
Greg runs workshops designed for owner builders, architects and building professionals, who get their hands on the raw material, building their own small hempcrete block. This is a miniature example that shows how hemp walls can be constructed, by lightly tamping hempcrete in place in between single or double-sided formwork. “Professionals come along and say, ‘Wow, this isn’t difficult at all!’,” grins Greg.
Houses that Greg is involved with are using single-sided forms. “We’re framing into the interior edge of a [400-450 mm] thick wall and lining the interior of the house with magnesium oxide building board, a gib replacement. Mag oxide board is inert, fire-resistant and it breathes with the hemp,” he explains.
There are other possibilities. “Boxing both sides around a timber frame is common in many parts of Europe,” says Graeme. “The wall is then clad for protection from the weather, especially wind driven rain, or simply plastered with lime plasters. Inside can be left as is, or any breathable natural finish [applied].”
Hemp can also be used as loose fill insulation and a flooring material. In Europe, large commercial buildings have been built with pre-fabricated hemp wall panels hoisted onto a post-and-beam structure.
Buildings made from hemp can have any kind of look you want, says Greg. For instance, the first US house built of hemp materials, in Ashville, North Carolina in 2010 – with which Greg and his Canadian based company were involved – is a high-end example of striking contemporary architecture (see www.gizmag.com/first-us-hemp-house/17115/ for photos and construction details). But hemp is also just as suited to natural renders that make a feature of the colour and texture of the natural fibre.
Notwithstanding information you’ll find on the internet, Greg is adamant that hemp is not suitable as a foundation material. “We know from history that hempcrete doesn’t work below ground. If subjected to constant moisture, it will break down and the lime will not carbonate. It’s the carbonation that preserves the hemp.”
Hemp construction underway
The Palmer house is being built on concrete foundations topped with insulated concrete forms. Building consent applications for this and other hemp houses have used alternative solution provisions provided in the New Zealand Building Code. The Palmer house was approved by the New Plymouth District Council in 20 days. “We introduced the building method first and asked the Council what information they wanted from us,” says Lance. “They were really good to deal with.”
“The building inspectors were pleased to see lime coming back,” says Greg. “We provided documentation from the US and Europe – and a sample block! The fact that the hemp was the aggregate was of no importance.”
The first New Zealand houses of hemp are being built with shiv imported from Europe but Greg wants to establish a Taranaki based co-op (a ‘hemp village’) that will grow and process hemp and produce local hemp products.
Meanwhile, plans are being drawn up for homes made with hemp and building consent applications have been lodged with Auckland and Waikato councils. The 14 projects between Dunedin to Northland range from expensive, architecturally designed homes to owner-builder homes that will be slowly completed as funds and time permit.
More information
- Hemp Lime Construction: A guide to building with hemp lime composites, Rachel Bevan and Tom Woolley, BREPress (Graeme North calls this ‘a definitive text’)
- Greg Flavall: www.hemptechnologies.co.nz
- Graeme North: www.ecodesign.co.nz
Interested in growing hemp in New Zealand? Growers, processors and suppliers require a license, administered by the Ministry of Health. Start here:
www.health.govt.nz/our-work/regulation-health-and-disability-system/medicines-control/hemp-industrial-hemp
Rachel Rose is establishing an urban permaculture property in Whanganui.
The ‘dirty dozen’ – latest update
/in Health and Food, Magazine ArticlesWhich foods in New Zealand are more likely to have pesticide residues?
What’s wrong with pesticide residues in food?
How can pesticide residues in food be reduced?
Alison White answered these questions in Organic NZMay/June 2010. Here she revisits them and gives us an update.
Which foods have the most pesticide residues? Grapes, celery, a range of fruit, pak or bok choi, spring onions, cucumber and bread are all ranked in the top dozen of foods available in New Zealand which are more likely to contain pesticide residues. Close contenders behind this ‘dirty dozen’ are apples, spinach, olive oil, muesli and tomatoes.
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Hemp: The comeback crop for building
/in FeaturesHemp is an ancient crop, grown for its fibre and put to thousands of uses. Unreasonably lumped in with cannabis, hemp was supplanted and restricted for nearly a hundred years – but it is now being heralded as an outstanding building material for our time.
We hope you enjoy this free article from OrganicNZ. Join us for access to exclusive members-only content.
New Zealand’s first house made of hemp will be finished this summer. Lance and Miranda Palmer are building a 195 m2 home in Taranaki using hempcrete for their walls.
Why hemp? “I wanted a home that would breathe naturally,” explains Lance. “When we learnt about hemp, it ticked all the boxes. It’s unusual in that it’s both a great insulator and yet provides a lot of thermal mass.”
Benefits for building
Hemp as a building material delivers an impressive list of benefits, say proponents like Greg Flavall, a builder and entrepreneur encouraging the use of hemp in New Zealand. He claims hempcrete is a carbon neutral or even carbon negative material. The fast growing hemp sequesters carbon and, once processed, the fibres are mixed with a lime and cement binder to create ‘hempcrete’. The lime continues to harden over time, absorbing more carbon as it calcifies. Some 110 kg of carbon is locked up per cubic metre of hempcrete, according to UK consulting firm Hemp-Lime Construct.
Hemp building materials are lightweight, insulating, and highly breathable, producing homes with excellent air quality, according to Greg. It’s fireproof and rodent and insect resistant. It’s extremely durable, with an expected lifespan of several hundred years. Hemp is also versatile; just vary the ratio of binder to make floors, walls, or insulation. And it can be deconstructed and recycled in another building project!
What it isn’t, is load bearing: hempcrete is being used in New Zealand as infill between timber structural framing.
Eco-architect Graeme North also has an interest in hempcrete but takes a more cautious view. He questions the claim about carbon neutrality, saying that manufacturing lime produces more carbon than it subsequently absorbs. “Claims of both insulation and thermal mass need to be considered carefully,” he warns, as it depends on the thickness and density of the wall.
Hemp growing in Taranaki
Different varieties of industrial hemp are grown depending on the desired yield (seed, fibre or fabric). They are alike in having extremely low levels of tetrahydrocannabinol (THC), the active ingredient in the Cannabis sativa grown for marijuana use: 0.3% compared with 3–22%.
A regulatory scheme was established in 2006 that makes it legal for license holders to grow, process and distribute hemp in specific circumstances. A grower must send crop samples to a lab before harvesting, to ensure THC levels are below prescribed limits. Crops not meeting this requirement may be destroyed. As at 23 September 2013, 27 licences to grow industrial hemp have been issued by the Ministry of Health, with a further two being processed.
Last summer, two Taranaki farmers working with Greg Flavall got their hemp licenses and 4.45 ha was sown, including at Avonstour, an organic, rare breeds family farm east of Stratford.
From field to house
Hemp is a fast-growing and robust annual broadleaf, with a root system that can extend two metres. It is naturally insect and pest tolerant and may not require fertilising.
Hemp’s history spans some 12,000 years, having been grown in Asia and the Middle East for fibre to make fabric, cloth and rope. It was grown extensively in the US from the seventeenth century. But its cultivation was outlawed in the US and UK in the 1920s and 30s when fears about cannabis use were running high, and fell away in Europe last century as hemp was supplanted by newer, synthetic fibres.
After harvesting, the plant is retted: soaked in water to loosen the fibres from the woody core. The fibres are separated out in a mechanical process called decortication before the stem is dried and chopped to produce shiv. To make hempcrete, the shiv is mixed with a small amount of hydrated lime-rich binder. Greg advocates a 5:1 mix of lime and cement, which means the binder is about two percent of finished volume. Natural pigments can also be added to create striking natural colours or patterns.
Greg runs workshops designed for owner builders, architects and building professionals, who get their hands on the raw material, building their own small hempcrete block. This is a miniature example that shows how hemp walls can be constructed, by lightly tamping hempcrete in place in between single or double-sided formwork. “Professionals come along and say, ‘Wow, this isn’t difficult at all!’,” grins Greg.
Houses that Greg is involved with are using single-sided forms. “We’re framing into the interior edge of a [400-450 mm] thick wall and lining the interior of the house with magnesium oxide building board, a gib replacement. Mag oxide board is inert, fire-resistant and it breathes with the hemp,” he explains.
There are other possibilities. “Boxing both sides around a timber frame is common in many parts of Europe,” says Graeme. “The wall is then clad for protection from the weather, especially wind driven rain, or simply plastered with lime plasters. Inside can be left as is, or any breathable natural finish [applied].”
Hemp can also be used as loose fill insulation and a flooring material. In Europe, large commercial buildings have been built with pre-fabricated hemp wall panels hoisted onto a post-and-beam structure.
Buildings made from hemp can have any kind of look you want, says Greg. For instance, the first US house built of hemp materials, in Ashville, North Carolina in 2010 – with which Greg and his Canadian based company were involved – is a high-end example of striking contemporary architecture (see www.gizmag.com/first-us-hemp-house/17115/ for photos and construction details). But hemp is also just as suited to natural renders that make a feature of the colour and texture of the natural fibre.
Notwithstanding information you’ll find on the internet, Greg is adamant that hemp is not suitable as a foundation material. “We know from history that hempcrete doesn’t work below ground. If subjected to constant moisture, it will break down and the lime will not carbonate. It’s the carbonation that preserves the hemp.”
Hemp construction underway
The Palmer house is being built on concrete foundations topped with insulated concrete forms. Building consent applications for this and other hemp houses have used alternative solution provisions provided in the New Zealand Building Code. The Palmer house was approved by the New Plymouth District Council in 20 days. “We introduced the building method first and asked the Council what information they wanted from us,” says Lance. “They were really good to deal with.”
“The building inspectors were pleased to see lime coming back,” says Greg. “We provided documentation from the US and Europe – and a sample block! The fact that the hemp was the aggregate was of no importance.”
The first New Zealand houses of hemp are being built with shiv imported from Europe but Greg wants to establish a Taranaki based co-op (a ‘hemp village’) that will grow and process hemp and produce local hemp products.
Meanwhile, plans are being drawn up for homes made with hemp and building consent applications have been lodged with Auckland and Waikato councils. The 14 projects between Dunedin to Northland range from expensive, architecturally designed homes to owner-builder homes that will be slowly completed as funds and time permit.
More information
Interested in growing hemp in New Zealand? Growers, processors and suppliers require a license, administered by the Ministry of Health. Start here:
www.health.govt.nz/our-work/regulation-health-and-disability-system/medicines-control/hemp-industrial-hemp
Rachel Rose is establishing an urban permaculture property in Whanganui.
From a farmer’s heart
/in Farming and Horticulture, Magazine ArticlesJanette Perrett shares her story of converting a Waikato dairy farm to organics
As a family we have been dairy farming all our lives. Neil and I built our herd up over time in the Waikato as we worked up through the ranks of contract milker to sharemilker and then to leasing properties. Fifteen years ago our youngest daughter left school to work on the farm and has been working with me as my ‘right-hand woman’ ever since.
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GE animal feed? No thanks!
/in Farming and Horticulture, Magazine ArticlesA piglet with a deformed spine.
Dead and deformed piglets are a problem where GE soy feed is used,
and Danish pig farmer Ib Borup Pedersen is convinced this is due to
glyphosate residues. Glyphosate is linked with reproductive problems,
birth defects, spontaneous abortions and a reduced live birth rate.
Growing reliance on supplementary feeds
Because chemical farming is reducing the ability to grow quality feed and the ability to withstand the increasing number of droughts, there is growing reliance on imported feeds to supplement the diets of our farm animals, mainly dairy cattle.
Typically these feeds consist of or include PKE (palm kernel expeller), canola, cottonseed, soy, maize and DDG (dried distillers’ grains, from maize).
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Beyond 1080
/in Farming and Horticulture, Magazine ArticlesDespite what the government would have you believe about the necessity of dumping a highly dangerous toxin from the sky, effective and safe alternatives to the poisonous war on possums are quietly springing up across the country.
Rebecca Reider investigates.
We knew there must be some better way than having 1080 poison dropped out of helicopters all over our community. In their endless quest to kill possums, the Animal Health Board dropped 1080-laced baits over 18,000 ha here in Golden Bay this past winter: in our forests, around rural properties, in the streams that supply our drinking water. If angry letters to the editor in the local paper are any indication, it riled up our community more than any other recent issue.
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How to create a GE-free zone
/in Features, Magazine ArticlesZelka Grammer encourages you to press for a GE-free zone in your city, region or district
We hope you enjoy this free article from OrganicNZ. Join us for access to exclusive members-only content.
Gardeners, beekeepers, seed savers, foresters, orchardists, organic growers and consumers: you know what’s at stake. GE experiments and releases present serious risks to our biosecurity, unique biodiversity, primary producers, economy and public health. Evidence of harm from GMO (genetically modified organism) land use overseas is irrefutable and continues to mount.
Here in New Zealand, we’ve held the line against GMO land use for many years. We have no commercial GE crops and firmly maintain our ‘zero tolerance’ policy for GE content in imported seeds.
Local government approach needed
Existing legislation for GMOs (the Hazardous Substances and New Organisms Act) is grossly inadequate, with a lack of strict liability and no requirement for the national regulator to take a precautionary approach. Ratepayers don’t want to end up forking out for GE experiments gone wrong!
By working constructively with our local councils, however, we can stop GMO land use. Independent reports and legal opinions commissioned by the Northland/Auckland Inter Council Working Party on GMO Risk Evaluation and Management Options (the ICWP) clearly show that local authorities do have jurisdiction to control GMO land use out of doors.
Here’s some information to help you create a GE free zone in your district or region or, at the very least, a strong precautionary GE policy to create an additional tier of protection for communities, and serve as a deterrent to those who wish to experiment with GMOs out of doors in our fair land. Outright prohibition (a total ban) of GMOs is also achievable.
What’s been done already?
A number of cities and areas of New Zealand have already been declared symbolic GE-free zones, including Nelson city, Napier, Waitakere, areas of Auckland like Waiheke Island, Western Bays, Mt Eden and Mt Albert, and various community boards in Northland and elsewhere. Buller District Council put in place a two-year ban on all outdoor GMOs.
All councils from South Auckland to Cape Reinga have precautionary or prohibitive GE policies in their long-term council community plans (LTCCPs), and precautionary GE policies in some annual plans.
Whangarei District Council ‘has adopted a precautionary approach to the management of biotechnology in general and to GMO land uses in particular. It will continue to investigate ways of maintaining the District’s environment free of GMOs (genetically modified organisms) until outstanding issues such as liability, economic costs and benefits, environmental risks, and cultural effects are resolved. Together with other Northland and Auckland councils on the Inter-council Working Party on GMO Risk Evaluation and Management Options, Council has committed to investigating possible local and/or regional management of GMO land uses under the Resource Management Act.’
Auckland City Council (now part of Auckland Council super city) has already set a precedent, achieving outright prohibition for all GMOs in its Hauraki Gulf and Islands District Plan since 1998.
Enforceable GE-free zones: rules with teeth
Even more desirable than symbolic GE free zones are concrete regulatory options (with methods, policies and rules) through the Resource Management Act 1991. To create an enforceable (rather than symbolic) regional exclusion zone for GMOs, we need rules with teeth in regional policy statements and/or district plans. A regional policy statement (RPS) is an overarching regional document for the next 10 years; content in the RPS must be given effect to by the district councils of the region.
Bay of Plenty Regional Council has precautionary GE wording in its proposed RPS. Northland Regional Council is considering right now whether or not to include a strong precautionary GE provision in its new RPS. The council received a huge number of submissions requesting this, including submissions from all the district councils and all Tai Tokerau Iwi authorities.
Such precautionary GE policies (provisions) can require those who apply to do GE experiments (and clear the easy hurdle of the Environmental Protection Authority – EPA – in Wellington) to abandon their plans or, if GE experiments aren’t prohibited outright, to post a substantial bond and be financially liable for unintended adverse impacts of EPA-approved GE experiments.
Local plans should place a strong emphasis on prevention of incursions of new organisms, GMO and otherwise (not just management/suppression of existing problem organisms). They should specifically identify GMOs as a threat, due in part to the nature of these self-replicating organisms containing controversial viral promoters etc., but also ongoing flaws/gaps in the HSNO legislation such as a lack of strict liability and the fact that ERMA is not required under the Act to take a precautionary approach to GMOs).
Councils working together to evaluate GMO risk
In Northland and Auckland, all councils have become full members of the innovative Inter Council Working Party on GMO Risk Evaluation and Management Options. The ICWP on GMOs was formed in 2003 as a direct result of strong lobbying and education of the councils by northern ratepayers.
Auckland Council and the Northland District Councils recently commissioned an independent section 32 analysis on GMOs (a requirement of the RMA), proposed plan change provisions, and a new legal opinion from Dr Royden Somerville, QC. This was done with a view towards a collaborative plan change to regulate GMOs in some way on a local level (this could include outright prohibition).
These new documents were made publicly available in February 2013, recommending that member councils of the ICWP on GMOs consider regulating the outdoor use of GMOs under the RMA through provisions in their planning documents.
Steps to a GE-free zone
Websites and contacts
The dangers of aspartame
/in Health and Food, Magazine ArticlesAspartame is a highly addictive artificial sweetener and flavour enhancer, used in over 10,000 products worldwide. Produced by genetic engineering, aspartame is incorrectly classified as an additive, when it is in fact an excitotoxic and neurotoxic drug, supposedly developed to treat peptic ulcers.
Misleading claims
Since its creation, aspartame has been known to cause cancer, and only received approval by the American Food and Drug Agency (FDA) through fraudulent means.1,2,3,4,5 Since then, advocates of aspartame have relied upon numerous flawed industry-funded studies (which avoided the detection of ill effects). This has resulted in the misleading claim that aspartame is one of the most studied food additives – and therefore, is the safest food additive ever made. Yet, as more research is done and more people become aware, the harmful effects of aspartame are harder to ignore.
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Magnesium: The life and death mineral
/in Health and Food, Magazine ArticlesOrganic NZ Magazine: November/December 2012 Section: Features Author: Dee Pignéguy
Dee Pignéguy shows how important magnesium is for our health.
The death in February 2010 of Ms Natasha Harris of Invercargill, just 30 years of age, made headlines when her partner told the news media that she died as a result of her addiction to drinking coke. The Guardian headline ‘Coca-Cola habit linked to New Zealander’s death’, was just one example of the worldwide coverage.
Pathologist Dr Dan Morin told the court main the cause of Ms Harris’ death was cardiac arrhythmia, but she also had a lack of potassium in the blood, which caused severe hypokalemia (NZ Herald, 20 April 2012).
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How natural is that flavour? The dangers of MSG
/in Health and Food, Magazine ArticlesAs consumer awareness grows about excitotoxins, the food industry is making it harder for consumers to avoid them. Kyra Xavia investigates.
An excitotoxin is a substance that excites nerve cells until they die. One of the most commonly used but best-hidden excitotoxins is processed free glutamic acid (MSG). Contrary to what the food industry says, MSG is shorthand for ALL processed free glutamic acid, including monosodium glutamate (which is processed free glutamic acid combined with sodium).
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Don’t read this article
/in Magazine Articles, RegularsIn this opinion piece Jon Carapiet raises concerns about the Trans-Pacific Partnership Agreement (TPPA), particularly around New Zealand’s GE-free status
It’s a bit hard writing an article about the TPPA, not just because I am no expert, but because of the secrecy that surrounds it. Like any secret, it is not open to scrutiny or evaluation. Even though we occasionally see mention of these innocuous-sounding initials, it seems the government is keen not to have public input on the TPPA negotiations. They’d rather you did not read this article or bother yourself with what this free trade agreement could mean for people living in New Zealand. The international calls for the draft agreements to be released have gone ignored and indeed these agreements are to be kept secret for years after a final agreement comes into force.
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Proudly published by the Soil & Health Association NZ
Proudly published by the Soil and Health Association NZ