The ISOBIO project has successfully developed a composite bio-based wall system that has shown exceptional hygrothermal performance and reliability, providing a new-build wall panel that can be industrialised and manufactured at scale, ready for integration into a complete pre-fabricated construction system for nearly-zero energy buildings.
To this end, ISOBIO partner Progetic has produced two guides that include seven opaque construction details for two different climates: cool-temperate (Lyneham, UK) and warm-temperate (Seville, Spain). The details show typical connections for ground floor>wall junctions, intermediate floor>wall, roof>wall and panel>panel junctions. Information relating to water-proofing, airtightness and vapour control is included.
All details have been modelled with 2-dimensional thermal bridge software, and designed to minimise heat loss and ensure minimum internal surface temperatures to avoid surface mould growth and condensation. Fabric U-values have been sized to meet the limiting heating and cooling demands required by the Passivhaus standard, using the PHPP (Passive House Planning Package) modelling tool for each climate (15 kWh/m2·a for space heating and 16 kWh/m2·a for space cooling in the warm-temperature climate).
The result is a set of construction details that comply with the Passivhaus standard, offering practical information to architects, contractors, developers and engineers who are looking to use the ISOBIO system in a low-embodied energy, nearly-zero energy construction.
December 5 is UN World Soil Day. The building industry has thus been called to account for its role in the massive use of mineral raw materials and environmental pollution.One solution comes from the bio-construction sector which draws on unlimited sources of natural materials such as hemp, which is a recyclable carbon sequestrator. But how comfortable is it to live in a hemp house?
Building with wood, straw, and hemp. Biobased materials are seeing ever more use in the construction sector, which needs to become more sustainable as it is one of the major sources of soil, air and water pollution.
“Forty percent of global raw material is consumed by the building industry. Fifty percent of CO2 emissions into the atmosphere come from the construction sector,” reports Italian bio-construction expert Paolo Ronchetti. Moreover, “Traditional building and insulation materials – of mineral or synthetic origin – are rarely recyclable. At the end of their life they are disposed of in landfills. Therefore, besides having an important environmental impact for their production, they have an equivalent environmental impact for their disposal.”
Biodegradable and from unlimited sources. Instead of exploiting the earth’s crust, and using a process that consumes energy and pollute, the bioconstruction sector can get its materials from the field. Hemp is one of the best examples; it can be grown in crop rotation and improves the quality of the soil. The plant is also a “carbon sequestrator”: it grows very quickly and acts as a carbon store, absorbing atmospheric CO2 for as long as it continues to exist.
Ronchetti adds: “You should consider that one cubic metre of a brick made from hempcrete – a hemp and lime biocomposite – instead of emitting C02, and polluting, it captures 20 kg of CO2 from the atmosphere. A cubic metre of low-density hempcrete biocomposite, which is sprayed to insulate roofs or subfloors, can remove 60 kg of CO2 from the atmosphere. So you can imagine – with the volumes and the numbers in the construction industry – how much this virtuous model of building with hemp and lime can fight climate change.”
To note, in the past, industrial hemp was banned in many countries because it was associated with illegal marijuana, from which it differs as the psychoactive compound ‘THC’ is present in proportions of below 0.2%. A thriving industry was consequently stopped. Now hemp farming is flourishing again.
This material also has other advantages. It allows builders to make high-performance envelopes and offers more comfortable, healthy and energy-efficient houses. Furthermore, the traditional building industry has increasingly used synthetic and chemical products that can be toxic and hazardous to human health. Tough low allergen design using natural materials is becoming a new trend.
Northern Italy, Chiari, near Brescia. “In the Po Valley summers are terribly hot and humid. Winters are cold and damp. Humidity rules here!’’ says Sara Bordiga. His husband, Mauro Cogi, longed for an eco-friendly home, and started studying all the available possibilities on the market. Finally, he opted for hemp and in 2015, Mauro and Sara moved into their new biobased house with their child.
“My husband’s choice really surprised me. I had never heard about hemp houses!” says Sara.
Mauro, an engineer, personally followed all the building phases. “The hemp technology works very well. I wrapped the whole structure in this monobloc hemp envelope, thus avoiding thermal bridges.” It’s monobloc because they didn’t use bricks, the hempcrete was sprayed directly onto the structural walls.
As this natural material is porous, it allows the building to “breathe”, avoiding any stagnant humidity. It also keeps a consistent temperature, thus cutting heating and cooling costs.
“Unlike what happens in homes with traditional polystyrene cladding, which doesn’t let moisture out, hemp allows good air exchange. This leads to very dry walls and high environmental comfort,” explains Mauro. “In this house, whose heating and cooling systems are only electric, the maximum power required is 1.8 kW, which is little more than a hair dryer. And with this 1.8 kW I can cool or heat 180 square metres.”
“Zero mould. Zero moisture,” confirms Sara. “And we’re doing well! There is a good level of comfort, we live well in terms of air and well-being.”
Hemp mixed with lime is the usual solution to insulate this kind of building. But European researchers, working on the project called Isobio, went further and developed a lighter but more rigid panel, with improved thermal conductivity. Thanks to innovative biobased binders, whose formula is still a secret, there’s no need for lime. This solution has breakthrough potential in the building sector.
Mike Lawrence, professor at BRE Centre for Innovative Construction Materials, University of Bath, UK, explains: “This material is the major innovation. It is a mixture of the hemp shiv – the woody part of the hemp stock – and it’s been mixed with the thermal setting binder which is also biobased, to make something which is rigid but strong… Much much stronger than you will get with hemp lime, which is much more brittle material. And it’s a lower density than hemp lime, and it’s much more flexible in the possibilities.’’
“The other innovation is a low density, a low thermal conductivity render, and that’s made up with also hemp shiv but it’s very fine. And this is mixed with lime. But because it’s so fine and because of the formulation of the lime, you end up with a render which is very high performance, very low thermal conductivity, much much better than a normal lime render. It’s laid in two layers, it’s got a reinforcement, it’s a sort of plastic grid which is put in between the two layers just to stop it cracking. And on the top – when you put these layers on – you put a standard lime plaster, a lime render which provides the resistance, the full resistance to the weather. Because hemp has the ability to absorb and desorb humidity, on the outside when it’s raining you don’t want that, so you put this out of surface, which will stop the water coming in,” he adds.
“Between the panels we put a fibre insulation. This insulation is made up primarily of recycled cotton, and it’s also got fibres from flax and from hemp,’’ Lawrence concludes.
The researchers are testing these and other innovations in different climates, in Spain and in the UK. They installed their composite panels in two demonstration buildings in Seville and in Wroughton, and now they are monitoring applied solutions. According to their results, they can achieve 20% better insulation performance than conventional materials, 50% less embodied energy and CO2 emissions, 15% reduction in total costs.
Oliver Style, energy consultant and researcher for Isobio says: ‘’I think that the real innovation is bringing together biobased materials, a lot of which have been used in traditional constructions for centuries, and applying modern solutions to make them fire-resistant, water resistant, to make them bind well and combining all of these different materials in a prefabricated wall system, which can be industrialised. I think up to now a lot of biobased construction has been very small scale, it’s been in the field of people who are very committed to biobased buildings, but it’s quite small scale, quite bespoke. So what we’re trying to do is create scalable solutions that can be built at industrial scale and which can make all of the requirements of the marketplace regarding thermal performance, fire performance, resistant to different weather conditions.’’
The composite panels should enter the market by the end of the decade. These biobased materials are expected to become ever more competitive in the next years, as the European Union requires all new buildings to be “nearly zero-energy”, which means very high energy performance, by the end of 2020.
By Loredana Pianta
27 November 2018
Journalists can download the video teaser and the BROLL [11’, original sound] in HD quality and scripts, free of rights and charge, here: mediacenter.youris.com
The use of natural materials is growing rapidly in Argentina and other South American countries. Technical progress and policy implementation seem to go hand in hand
The green building phenomenon in Latin America has taken off. Bio-based aggregates have started penetrating the construction sector’s market, and the development of eco-friendly renewable products has increased the use of bio-based polymers in the construction industry, as a recent study shows.
South America is one of the emerging markets where a major demand in natural materials for buildings is expected in the next years. People today are indeed increasingly persuaded that they can safely get the same quality level as traditional products.
The policy implementation in the region following suit. Brazil, Mexico, Colombia, Chile and Peru have carried out different measures ranging from relevant tax cuts to soft loans for sustainable construction.
Although in Argentina this is still a new phenomenon, the situation and legislation are quickly changing. “In my country public interest and the market are also growing because young people are getting involved and interested in this topic,” says Juan Manuel Vazquez, an Argentinian agricultural engineer, who started using bio-based material for construction 15 years ago.
“I was working in an agronomic olive oil industry and I found that olive oil can lose quality in storage, in particular in countries with extreme climates. That was also when I first heard about straw bale warehouses, used for storing bulk food because of their insulation properties,” he told youris.com.
He later became co-founder of Henia Carbono Negativo, a company that develops pre-assembled panels of straw bales, using 100% biological material for dry construction, with high thermo acoustic, mechanical and fireproof performances. It was in La Cumbre, Córdoba, that they built their first family house of 250 m2.
“We are now working to conquer the mass market, it will take time but not that much,” affirms the expert with conviction. “I recognise that my method may be a niche one, but I think that economic paradigms are changing. People are willing to pay a little more for green materials because it’s a matter of health and well-being.’
An eco-friendly house in Argentina would cost only 10% more than a traditional one, on the basis of Manuel Vazquez’s estimations. He also says that thermal insulation is seven times greater than that produced by a double hollow brick wall.
It is also resistant to fire and earthquakes. The straw used is kept compact, and without moisture, and it does not attract insects of any kind. High insulation potential, no pollution, and the fight against climate change are just some of the reasons which motivate him.
Henia’s experience is in line with ISOBIO, a EU project that proposes a strategy to mainstream bio-based construction materials. This is another source of inspiration for Manuel Vazquez. According to the European researchers, bio-based construction materials are in fact capable of achieving a 50% reduction in embodied energy and CO2 emissions, with 20% better insulation properties compared to conventional materials such as bricks, cement and beams in walls and roofs.
There are several signs of policy changes to promote energy efficiency in Argentina’s buildings. For example, the city of Rosario has implemented a certification, carried out in 500 homes, which enabled household performance and energy-saving potential to be identified.
Specialist in bio construction Maria Loreto Retamales lives in a bio-based house in Valparaiso, in Chile, but her first eco-friendly house was in Argentina. “Ten years ago, I decided with my family to live in harmony with nature,” she explains. “I read about the architect Nader Khalili, his Cal Earth Foundation (California Institute of Earth Architecture), and his research and work with soil and sack.”
She studied his technique called “SuperAdobe”, a form of earth bag architecture, and now she trains other people on it as well. “In less than a year, I even gave workshops to architects and engineers in Argentina, Chile and Bolivia,” she tells us.
House built with the SuperAdobe technique. Photo credits: Maria Loreto Retamales
Maria Loreto has no doubt: “Living in a natural building has big advantages such as a more stable temperature and humidity. People don’t get ill so much. Moreover, earth isolates from the sun’s radiation and electromagnetic waves.”
Argentina has one of the most recognised bio constructors in the world, Jorge Belanko, specialised in earth buildings. Of course, this technique still remains quite unusual, but in the last 10 years Maria Loreto has seen hundreds of innovative projects developing.
Finally, one of the architectural symbols of the growing movement of natural builders in the country, is Tol-Haru, la Nave Tierra del Fin del Mundo, the first self-sufficient house in Latin America. It was built in Ushuaia, the closest city to Antarctica in 2014, using recycled materials. Wind and solar energy provide heating and cooling. The shelter also reuses rainwater and it even recycles waste.
A new sustainable initiative in Bristol, in the UK, uses bio-based materials to face the need for additional and affordable housing supply
Bristol is at the forefront of high-tech innovation in the UK, named European green capital in 2015. But it is also the second least affordable major British city housing-wise only after London.
Its estimated population is 454,200 people, according to the Office for National Statistics (ONS). Around 10,000 people are registered on the waiting list for a council home. There is a serious housing problem affecting both the young and the old.
To face the emergency, the Knowle West district is testing a new solution that is eco-friendly at the same time. We visited this neighbourhood in the south of Bristol, to discover how a community is trying to make possible a sustainable, affordable housing model using bio-materials.
The initiative, called We Can Make, gathered architects, designers, academics, policy makers, and residents. The result is a prototype house built on the grounds of a community centre, with the cooperation and participation of locals in the construction, plumbing, handmade carved furniture, art, and interior design.
The TAM (Transportable Accommodation Module) was designed and built using bio-materials such as straw, compress straw, and timber. These carbon capturing materials minimise their environmental footprint.
The building is cool in summer and warm in winter, saving hundreds of pounds per month in air conditioning and heating. Actually, as soon as we entered the house, the temperature and the moisture in the environment were right despite the cold weather and rain outside.
According to Dr. Charles Gamble, our guide and head of Innovation at Stramit International, which is part of CooBio company, the TAM uses 90 percent less energy to heat and light when compared to the UK average.
Dr. Charles Gamble, head of Innovation at Stramit International, shows samples of the compressed strawboard panels used in the TAM (By Susan Fourtané)
“The panels are made of compress straw and strawboard framed in timber and covered in clay,” he told youris.com. “Compress straw board has been around for almost 70 years since the technology was invented in Sweden in 1950. The process, also developed in the UK, provided building materials for more than a quarter million houses from the 50s to the 70s after which it became impossible to compete with plasterboard,” he added. These natural retrofitting solutions are also currently being tested at demonstration sites in the UK (Bath) and Spain (Seville) under the EU project Isobio.
Residents who have tested the TAM space overnight have reported that they slept better than usual, which is attributed to a good quality of air in the ambience. External people can rent it through Airbnb, and the income goes to the community centre.
“It’s the breathable nature of the building,” confirmed Finlay White from ModCell, which provided the straw panel systems, when we asked the difference from the traditional Victorian houses in England. “Around the windows in the buildings you don’t get condensation. This is one of the health benefits of using bio-materials,” he explained.
“The mapping of the Knowle West area identified thousands of small plots of land where TAMs could be put to relieve the housing situation for many of the families here who are stuck, because they have no employment or they’re too old. Sometimes you have three or four generations living in a small house,” Gamble said.
“A salary is £23,000 a year. The average price house is 8.4 times that,” added White, while the TAM cost for 36m2 is £90,000, with both leasing and hire purchase options.
“What ‘We Can Make’ offers is a model that can be replicated in other regions involving local communities to develop in spaces that they privately own or the council owns, constructing the TAM systems locally to solve housing crisis,” said Gamble.
The team intends to place the houses approximately 200 metres from the community centre, hiring local people to help build the panels creating about 21 jobs in the location.
According to White, there have been identified 1500 potential sites in this area with seven similar more estates in Bristol, and “there are estates like these all over the UK that have the same housing issues.”
Hundreds of construction professionals were introduced to ISOBIO’s innovative bio-based solutions at the Ecobuild trade fair in London last week, the UKs largest event for sustainable building products.
The ISOBIO stand was busy throughout the three day exhibition, with visitors keen to learn how partners are developing new scalable natural products with improved resistance to fire and decay.
Large samples of the ISOBIO systems for new build, external and internal retrofitting were on show, enabling visitors to see and feel for themselves the properties of natural materials, which are known to have benefits for the environment and for health when used in construction.
The question on everybody’s lips was: ‘where can we buy it?’ Well the novel ISOBIO panels and plasters are currently being tested at demonstration sites in the UK and Spain. They will be available on the market by the end of the decade: so watch this space!
We were handing out postcards describing the different ISOBIO product prototypes which you can download here
Scientists from ISOBIO attended the second International Conference on Bio-Based Building Materials (ICBBM) in Clermont Ferrand in June of 2017. Dr Mike Lawrence from the University of Bath delivered a plenary talk on Innovations in the use of bio-based aggregates in construction, charting the development of research leading to the cutting-edge research being conducted in ISOBIO.
Technical research conducted as part of the ISOBIO Project inspired the presentation of 5 papers at the conference. This included 2 papers prom the University of Bath, 2 papers from the University of Rennes 2, and one paper from CAVAC.
266 delegates from 40 countries attended the conference to listen to 150 presentations. As well as sharing scientific knowledge through presentations, there were opportunities for networking with scientists in different fields, but all with the shared goal of minimising the environmental impact of construction through the use of bio-based materials.
ISOBIO workshop has just concluded at Acciona Construcción premises and the echo of its outcome conveys a story of successful collaboration and knowledge transfer among innovation project in the domain of eco-construction.
The event has showcased bio-based products and solutions for new buildings and retrofitting projects, currently under development in three EU funded projects, ECO-SEE, OSIRYS and ISOBIO. Experts from the projects shared their achievements and experience in bio-based panels and plasters for novel insulation, in panel and coating products, forest-based biocomposites for façades and interior partitions and on how bio-based products can be incorporated into low energy building design.
ISOBIO construction activities are now being carried out at Acciona premises.
The project demonstrator is now coming to life and all project results are being delivered and assembled to demonstrate the wide range of configurations and solutions developed in ISOBIO, including an insulation system for new buildings as well as sytems for internal and external retrofitting of extising buildings.
Claytec is a German SME which produces a series of clay based products and systems. These include clay plasters, colors, boards, and blocks as well as interior insulation solutions. Within ISOBIO Claytec have investigated how adding bio-based aggregates could improve the properties and performance of their plasters. They have developed three new clay plasters that incorporate hemp powder as a bio-based aggregate. The plasters use earthen clay as a binder, and pumice and sand as the mineral aggregates. In addition, a silica based fire retardant additive was added in one of the plasters.
Functions
The Claytec plasters are packaged in the form of ready-to-use mixtures and are compatible with standard plaster machines. They are suitable for interior use. The three ISOBIO plasters were developed specifically for use as a fire protection layer on bio-based substrates such as rigid hemp insulation panels, compressed straw boards and wood fibre boards.
Impact
Clay in itself can be deemed advantageous as a construction material. It improves the indoor air quality, has a favourable environmental footprint, and is easy to use. The tailor made modifications developed in ISOBIO should improve their fire protection capacity and workability on bio-based substrates, while providing a constant moisture buffering effect (>65gr/m² (class III DIN 18947). These improvements are not expected to increase costs compared to standard clay plasters.
Cavac Biomatériaux is a subsidiary of the French Agricultural Cooperative Cavac, and specialises in the production of biobased insulation products for the building market. Within the ISOBIO project they have developed a new product: a rigid insulation panel made of hemp.
The panel is composed of a commercial hemp shiv grade bonded using a specially formulated thermosetting bio-based binder, developed in collaboration with UR1. The panel manufacturing process has been validated on existing industrial tools and panel prototypes have been installed at ISOBIO demonstrators.
Functions
The rigid panel can be used for internal or external insulation, or as a substrate for renders or plasters. A tongue and groove system has been developed for easy installation and to prevent thermal bridging.
The insulating panel offers a low thermal conductivity and embodied energy while maximising the moisture buffering value and mechanical properties. Research on additives showed that improved water repellence and fire performances can be obtained.
Impact
This product brings a new valorisation to hemp shiv aggregates (a byproduct of the hemp transformation). The biobased binder offers an eco-friendly and harmless alternative to formaldehyde and isocyanate adhesives.
The compatibility with dry manufacturing processes also significantly reduces the embodied energy when compared to existing wet processes.
BCB is a French company which provides lime solutions such as mortars, washes or renders for exterior and interior masonry, and rendering for all types of architecture.
BCB is conducting research into eco-friendly materials by broadening the scope of application for lime. Within the ISOBIO project they have developed a novel bi-component product made of lime combined with hemp aggregates.
Functions
The novel plaster that has been developed can be used both for internal and external application. The plaster can be applied to old as well as new substrates, including concrete, cellular concrete, lime-based undercoating, stone, and wood panels. The product has also adheres well to bio-based substrates, such as the hemp panel developed by CAVAC. Implementation is made by spraying.
In case of external application, it should be covered with a fine layer of lime-sand render to protect the wall from weather conditions. When used internally, the plaster provides a decorative finishing layer. Because of its vapour permeability, it also ensures a comfortable habitat in term of humidity and temperature regulation.
Impact
The inclusion of bio‐based materials ensures that whole life energy use is reduced through taking advantage of the photosynthesis of atmospheric carbon, which is sequestered in the fabric of the building. The plaster does not contain sand, which also considerably reduces its carbon impact. Moreover, application of the plaster is easier due to its density being much lower than usual finishing plasters.
Compressed Straw Board (CSB) is a wall construction and lining material made in a continuous process by heating straw under pressure in a Stramit International machine.
A solid board is produced which is 100% pure straw, without extra binder, the lignin in the straw being sufficient to act as a binder during the process. Normally it is covered with a paper cover during the process.
CSB is produced in solid self supporting boards in thicknesses of 40 or 60mm and 800 or 1200mm widths, at selectable length between 1.5 and 3.9m.
Functions
CSB is used to face the internal wall and ceiling surfaces of buildings by fixing to the structure, and can form self supporting internal walls (partitions). It can be plastered in clay or gypsum, to a fine finish.
CSB has a thermal conductivity value of 0.1 and as such is part of the thermal function of a building, usually supplemented by less dense insulation. It is vapour permeable and contributes to the moisture balance within a building, buffering changes in air humidity. Being of medium density CSB acts as a sound absorber and contributes to acoustic insulation between rooms in a building. A single 60mm board with a plaster finish provides 60 minutes fire resistance.
Impact
CSB demonstrates low embodied energy. It is 95% straw – a waste product of agriculture gathered into bales and transported to the processing plant. Processing CSB therefore uses little electricity.
Carbon Dioxide is sequestered at the rate of 1.5kgCO2e/kg or 30kgCO2e/m², considering only the straw component. Being a natural biological material the VOC content is negligible, contributing to a healthy indoor environment.
The 2017 edition of the Applied Nanotechnology and Nanoscience International Conference (ANNIC) was held in Rome, Italy from Wednesday 18th to Friday 20th October 2017.
This third edition of the conference gathered more than 280 delegates (mainly from academia) from 51 countries. Plenary sessions were held in the morning, whilst poster sessions and talks took place every afternoon. The ISOBIO project was showcased during the last day. The audience showed a lot of interest in the progress and technology presented, which highlighted the fact that using bio-materials for construction could be a solution in countries where conventional construction materials are more expensive. Finishing on a joyful note, the best talk prize, presented by Environmental Science: Nano – The Royal Society of Chemistry, was awarded to Marion Bourebrab (PhD student based at TWI Ltd.) for her presentation ‘Development of highly repellent silica nanoparticles for protection of bio-based insulation composite materials’.
Research has made affordable, environmentally-friendly houses a reality. The first super-insulated, low-carbon straw houses are hitting the open market.
Many technologies have promised these qualities, but few have been commercially viable. What’s been lacking is the performance data needed to demonstrate that these technologies are durable, genuinely environmentally beneficial, and suitable to be insured.
Over the past 13 years, our Department of Architecture & Civil Engineering has led on research into straw as a low-impact building material. This work, which has included developing a unique straw bale panel as well as scientific monitoring and testing, has now culminated in crucial industry certifications.
… Continue reading the original article on University of Bath website, here.
ISOBIO aims to develop new bio-based insulation panels and renders, and to scale them for mainstream adoption by the building and construction industry. ISOBIO researchers have been working on ways to improve their resistance to fire and decay. Dr Mike Lawrence from the BRE Centre for Innovative Construction Materials at the University of Bath explains how the application of high technology film coatings can help.
The benefits of using plant-based materials in construction are well known. They absorb carbon dioxide from the atmosphere through photosynthesis, generating oxygen and water in the process, so when incorporated into a building offer the possibility of carbon negative construction. One possible drawback is that these materials, being carbon based, are intrinsically flammable, and susceptible to decay.
The traditional way of dealing with these issues is either to protect the material by good detailing or to incorporate fire protective chemicals such as Borax. Researchers at the University of Bath and TWI have been looking at a radical new approach, by coating the individual particles with a microscopic layer of silica, one billionth of a metre in thickness, so thin that it is completely invisible except under a scanning electron microscope.
In spite of the small amount of material being used, the researchers have shown that this layer can not only give added fire resistance, but by using some clever chemical manipulation, the layer can make the particles hydrophobic. This resistance to water means that agents of decay such as bacteria and fungi, cannot reproduce, making the material much more robust. This means that the materials will last longer and will be much more resilient to disasters such as flooding.
These scientific advances will be incorporated into the novel ISOBIO panels and plasters that will be available on the market by the end of the decade.
Scanning Electron Microscope image showing pores in hemp shiv (x 6500 magnification)
Scanning Electron Microscope image showing pores in hemp shiv coated with nano-silica (x 6500 magnification)
ISOBIO aims to develop new bio-based insulation panels and renders, and to scale them for mainstream adoption by the building and construction industry, but just how much do we actually know about the bio-materials we are proposing to use? ISOBIO researchers have been working on deepening our understanding of these amazing materials
It is well known that plant based materials offer great benefits in the field of construction. They absorb carbon dioxide from the atmosphere through photosynthesis, generating oxygen and water in the process, so when incorporated into a building offer the possibility of carbon negative construction. Experience has shown that bio-based materials have the capability to manage the internal air quality passively, producing much more healthy living environments.
Just how this works, and why plant based materials perform so well has been the subject of research for several decades. ISOBIO researchers at the University of Bath in the UK and the University of Rennes 1 in France have been delving deep into the microstructure of plants and have discovered some remarkable characteristics.
These plants have complex interlinked pore structures, designed by nature to transport moisture and nutrients. When incorporated into buildings these same pores not only provide excellent levels of thermal insulation but also buffer moisture, resulting in steady humidity levels in rooms reducing the need for air conditioning.
Plants such as hemp, oil-seed rape, flax, wheat and corn-cob all offer varying degrees of insulation and moisture buffering, and the researchers within the ISOBIO project are developing a detailed understanding of the mechanisms involved and ways to optimise their performance. This understanding is being incorporated into the novel ISOBIO panels and plasters that will be available on the market by the end of the decade.
From the use of Gore-Tex-like waterproof fabrics to the development of “breathable” bio-based materials, the construction industry is chasing breakthrough solutions to insulate buildings and keep living areas free from damp and mould
Today, one of the new challenges for the construction industry is the use of textiles, coming from the clothing and footwear industries. Gore-Tex-like membranes, which are usually found in weather-proof jackets and trekking shoes, are now being studied to build breathable, water-resistant walls. Tyvek is an example of one such synthetic textile being used as a “raincoat” for our homes.
Camping tents, which have been used for ages to protect against wind, ultra-violet rays and rain, have also inspired the modern construction industry, or “buildtech sector”. This new field of research focuses on the different fibres (animal-based such as wool or silk, plant-based such as linen and cotton and synthetic such as polyester and rayon) in order to develop technical or high-performance materials, thus improving the quality of construction, especially for buildings, dams, bridges, tunnels and roads. This is due to the fibres’ mechanical properties, such as lightness, strength, and also resistance to many factors like creep, deterioration by chemicals and pollutants in the air or rain.
“Textiles play an important role in the modernisation of infrastructure and in sustainable buildings”, explains Andrea Bassi, professor at the Department of Civil and Environmental Engineering (DICA), Politecnico of Milan, “Nylon and fiberglass are mixed with traditional fibres to control thermal and acoustic insulation in walls, façades and roofs. Technological innovation in materials, which includes nanotechnologies combined with traditional textiles used in clothes, enables buildings and other constructions to be designed using textiles containing steel polyvinyl chloride (PVC) or ethylene tetrafluoroethylene (ETFE). This gives the materials new antibacterial, antifungal and antimycotic properties in addition to being antistatic, sound-absorbing and water-resistant”.
Rooflys is another example. In this case, coated black woven textiles are placed under the roof to protect roof insulation from mould. These building textiles have also been tested for fire resistance, nail sealability, water and vapour impermeability, wind and UV resistance.
Production line at the co-operative enterprise CAVAC Biomatériaux, France. Natural fibres processed into a continuous mat (biofib) – Martin Ansell, BRE CICM, University of Bath, UK
In Spain three researchers from the Technical University of Madrid (UPM) have developed a new panel made with textile waste. They claim that it can significantly enhance both the thermal and acoustic conditions of buildings, while reducing greenhouse gas emissions and the energy impact associated with the development of construction materials.
Besides textiles, innovative natural fibre composite materials are a parallel field of the research on insulators that can preserve indoor air quality. These bio-based materials, such as straw and hemp, “can reduce the incidence of mould growth because they breathe. The breathability of materials refers to their ability to absorb and desorb moisture naturally”, says expert Finlay White from Modcell, who contributed to the construction of what they claim are the world’s first commercially available straw houses, “For example, highly insulated buildings with poor ventilation can build-up high levels of moisture in the air. If the moisture meets a cool surface it will condensate and producing mould, unless it is managed. Bio-based materials have the means to absorb moisture so that the risk of condensation is reduced, preventing the potential for mould growth”.
The Bristol-based green technology firm is collaborating with the European Isobio project, which is testing bio-based insulators which perform 20% better than conventional materials. “This would lead to a 5% total energy reduction over the lifecycle of a building”, explains Martin Ansell, from BRE Centre for Innovative Construction Materials (BRE CICM), University of Bath, UK, another partner of the project.
“Costs would also be reduced. We are evaluating the thermal and hygroscopic properties of a range of plant-derived by-products including hemp, jute, rape and straw fibres plus corn cob residues. Advanced sol-gel coatings are being deposited on these fibres to optimise these properties in order to produce highly insulating and breathable construction materials”, Ansell concludes.
Houses built with bio-based materials, such as timber, straw and hemp, act as CO2 banks. Experts explain how citizens can become custodians of atmospheric carbon dioxide and thus help reduce air pollution
Domestic efforts play an important role in curbing global warming. Besides producing and using renewables, homes can also act as banks that store CO2. This innovative building model exploits bio-based materials, such as timber, straw and hemp, which act as “carbon sequestrators.”
Carbon is banked through photosynthesis made by plants during their lifetime. “Photosynthesis is the means with which plants absorb atmospheric CO2 molecules, and split them into their component atoms. The carbon atom is retained making complex organic sugars that are the building blocks of the cellulose, hemi-cellulose and lignin found in plant cell walls. The oxygen atoms are released back into atmosphere as a by-product. Therefore, photosynthesis converts atmospheric CO2 into carbon-based materials that we can use to build and insulate our houses”, says Finlay White, expert in low energy “passive” buildings.
When plants die, the ground absorbs the stored carbon dioxide, which then finds its way back into the environment. However, if we use bio-based materials in construction, the CO2 remains “imprisoned” in the buildings made.
But how much carbon dioxide can be stored in a carbon sequestration house? White explains that “depending on the extent of the renewable materials used, the gross amount of CO2 equivalent stored could be as much as 55 tonnes for a typical 80m2 house. Such dwellings would typically use timber framing for the superstructure and for the internal walls and floor, straw bale insulation in the roof, timber for the cladding and finishes, and other bio-based materials for use elsewhere.”
“The gross amount is the actual CO2 absorbed by the bio-based materials used in the building. The net amount will need to take account of the energy used and subsequent CO2 emissions associated with dealing with the forests and crops, and turning the materials into useful building products and delivering them to site. This is known as embodied carbon”, he adds.
“Therefore the calculation for a bio-based house will be the gross CO2 captured minus the CO2 emissions embodied in making the house. A typical 80m2 bio-based house with a gross CO2 capture of 55 tonnes might well mean a net amount of 33.6 tonnes.”
White works for the Bristol-based green technology firm Modcell, which contributed to the construction of what they claim to be the world’s first commercially available houses built using straw (more info in this BBC report).
They are also collaborating with the European project Isobio, which is developing “new products that include compressed straw board that can replace plasterboard, cereal fibres combined with bio polymers to make components for door cores etc.”, says White, “Once a designer becomes aware of the use of bio-based materials, the potential for their use expands rapidly.”
Carbon sequestration houses still remain a niche market in Europe.
Callum Hill, senior visiting research fellow at the University of Bath, another Isobio expert in the field, points out that “the building industry tends to be very conservative in its approach and prefers to use what it is familiar with. Bio-derived materials are often perceived as being perishable, flammable and short-lived. These perceptions are not supported by facts”. Compressed straw bales used for building envelopes, for example, are not flammable because they contain less oxygen.
Hill thinks that governments should recognise this alternative storage of atmospheric carbon dioxide and “provide a financial benefit for custodians of it. “It is a way of storing atmospheric carbon dioxide that can be readily achieved and without financial penalty (unlike carbon capture and storage)”, he says, “This is something that can be done to the benefit of society and the environment. Anthropogenic carbon emissions are undoubtedly changing the climate and these will have huge financial implications”.
The National Structural Integrity Research Centre (NSIRC) announced the winners of The Welding Institute and the Armourers & Brasiers’ Gauntlet Trust Awards 2016.
The best PhD student prize was awarded to Marion Bourebrab, from TWI innovation partner and ISOBIO coordinator, who has been awarded for her study “Enhancing bio-materials’ properties: bringing hydrophobicity and fire retardancy”, which tackles the inherent risk of bio-based materials of low fire resistance and water penetration.
Water repellence and fire retardancy will be achieved through ISOBIO innovation achievements with a single sol-gel based treatment of the bio-based materials, without affecting the materials’ breathability to prevent condensation within the panels.
ISOBIO research is achieving promising results in treating hemp shivs. The latest development by the innovation partner TWI lead to impressive results in terms of water repellence (up to 130° of water contact angle) and of hydrophobic properties (water contact angle, above 90° and maintaind for over 20 minutes).
These achievements are promisingly converging towards the main objective of developing bio-based materials with high insulating properties, low embodied energy, low embodied carbon and hygrothermally efficient.
ISOBIO is emerging from the research phase and taking its first steps towards its target market. Bringing innovation and research outcomes to the attention of experts and stakeholders is essential to tackling some of the possible challenges in the industrialisation phase.
Against this backdrop, ISOBIO innovation partners held a workshop on 14 September this year at the University of Bath. The aim was to stimulate discussion about bio-based insulation materials and the associated environmental and LCA issues. The workshop took place alongside an event held by the Alliance for Sustainable Building Products (ASBP), focusing on embodied carbon issues and providing useful insights and strategies for reducing it.
ISOBIO had the opportunity to share knowledge about major topics such as life cycle assessment and cost analysis, key results of demonstration actions (including, carbon sequestration, waste minimisation, efficient energy and raw material use) as well as a case study of a nearly-zero energy residential building made with straw bales and timber. This highlights a strong link among bio-based building systems, energy efficiency and indoor comfort, allowing strong connection between the bio-economy and energy sectors to be created. The workshop was also an opportunity to hear about ASBP activities associated to the challenges of applying LCA and Life Cycle Costing (LCC) to external thermal insulation composite systems and to embodied carbon policies and decision making tools.
LCA and LCC are essential aspects that can bring research outputs closer to the target market. Engaging with stakeholders, sharing knowledge and best practices is key to stimulating stakeholders’ acceptance of the designed bio-based material, which aims to turn a niche innovation into a mainstream product of the construction sector. ISOBIO is taking its first steps in this direction and, little by little, it will need to address all challenges of industrialisation, firmly drawing on its particular strengths and exploiting the opportunities ahead.
The bioeconomy comprises sectors that use renewable biological resources to produce food, materials and energy. It is at the centre of several global and EU challenges in the near future such as the creation of growth and jobs, climate change, food security and resource depletion.
Several policy and action plans have been endorsed, among which the Bioeconomy Action Plan (2012) takes a particular integrative approach, comprising all those sectors of the economy that use renewable biological resources from land and sea – such as crops, forests, sh, animals and micro-organisms – to produce food, materials and energy.
The Drivers of European Bioeconomy in Transition report includes a detailed contemporary ‘business as usual’ projection to 2030 with accompanying alternate narratives representing two hypothetical policy pathways. Employing a useful decomposition technique, the reader is given insightful access to the relative role of economic and policy drivers in shaping market trends. Furthermore, by comparing policy narratives with the reference scenario, the report assesses both the resilience of EU’s bioeconomy in fulfilling a diverse portfolio of policy goals and identifies potential policy conflicts and trade-offs.
Sustainable, affordable materials play an important role in improving air quality in cities. In the framework of COP21 goals, the EC launched a contest to develop an innovative and well-designed material solution that will reduce the concentration of particulate matter in the air.
The desing of innovative materials have an impact not only on the bioeconomy and energy sector, but in the health sector and tackling climate change issues and ecosystems likewise.
The contest will be open untill January 2018. For further info, visit the Horizon Prize website.
ISOBIO aims to develop new bio-based insulation panels and renders, and to scale them to mainstream adoption in the building and construction industry. A purpose driven by a common vision: the less we intervene on materials, the more we achieve.
In ISOBIO, innovation is coming straight from nature: fibres and straw are some of the raw materials at the core. Scientists and stakeholders do acknowledge this but demonstrating this vision presents a number of research and technical challenges. This could be a niche market, and a highly eco-friendly one.
The University of Rennes hosted the first regional stakeholder workshop on 4 February 2016. It brought together academia and research stakeholders to tackle the main challenges of the project’s objectives and to explore opportunities offered by bio-based construction materials.
Multifold barriers were identified that need to be overcome if bio aggregates are to be widely adopted across the construction sector: technically, the challenge is to do with confidence in producing raw materials and meeting the technical standards for natural insulation materials. Scientifically, water repellence and fire resistance are essential issues under the microscope.
Behind the uptake of bio-based aggregates, there is an even more substantial question: is the market ready for them? This raises the issues of public perception and market penetration. Persuading users that they can safely benefit from bio-based materials may be as challenging as reaching the market penetration level required to replicate the solution developed while keeping the same quality level of the final product.
The workshop enabled a wide range of research and academia stakeholders to engage directly with one another and explore these challenges, in view of working together towards ISOBIO’s aim of widespread adoption and design of a bio-based product with high-insulating properties, low embodied energy and carbon, hydrothermally efficient, greening the building and construction industry.
ISOBIO, sustaining its dissemination potential during ECO-binder event.
Within the framework of the collaboration in the AMANAC Cluster, ISOBIO innovation has been featured during ECO-binder workshop held in Bilbao on February the 4th. The main objective of the workshop was the initiation and assessment of the challenges and development opportunities in the area of low embodied energy materials and energy efficient buildings.
ISOBIO had the opportunity to show its potential benefits for the society, the project objectives and expected impact as well as its inclusion in the AMANAC cluster. ACCIONA took part to the workshop and disseminated ISOBIO innovation towards experts and stakeholders in the field.
The impacts of the Paris Agreement on green business environment: The role of the private and public sectors, the effects in terms of legislative & legal frameworks and possible benefits for novel construction materials
“History will remember this day,” said Ban Ki-moon, secretary general of the United Nations, moments after the green-topped gavel, symbol of the Paris talks, was dropped on what is considered the most ambitious deal on climate change that the world has ever seen.
Participating countries include Austria, Brazil, Cameroon, Canada, Finland, France, Germany, Indonesia, Japan, Mexico, Morocco, Norway, Senegal, Singapore, Sweden, Tunisia, Ukraine, United Arab Emirates, and the United States. Furthermore, over 60 organisations are members of the alliance.
The World Green Building Council is a key member of the initiative. “While the Paris Agreement is not itself legally binding, many countries will choose legislative and legal frameworks to support its implementation,” says Terri Wills, CEO of the World Green Building Council, a network of national green building councils in more than one hundred countries. Many of them are working closely with their national governments to develop renovation strategies.
“Some countries will opt for a ‘carrot’ over a ‘stick’ approach” adds Wills, explaining that “they will decide to offer incentives in the form of subsidies, grants for ambitious green building projects, or planning approvals for extra building space if a building complies with a green certification standard.”
The COP 21 Paris Agreement has put emphasis on the construction sector and on the adoption of novel building materials, designs and technologies.
“States should provide long-term incentives and support for emissions reductions to show real commitment to change. Policy actions could include carbon pricing, ambitious buildings standards and targeted spending on new technologies through green public procurement”, says Simon Hunkin from Greenovate!Europe. The independent expert group, dedicated to developing sustainable business, is collaborating with a research project called ISOBIO, which aims to develop bio-based materials as an alternative to traditional insulations while reducing their cost.
The researchers are developing a new approach to insulating materials, through the combination of existing bio-derived aggregates with low embodied carbon and innovative binders to produce durable composite construction materials.
With these novel composites, the aim is to cut embodied energy and carbon dioxide at component level by 50%, and to improve insulation properties by 20% compared to conventional material. The study will also seek to demonstrate a reduction in total costs by 15% and in the total energy spent over the life time of a building by 5%.
But could such biomaterials be commercially attractive? “To a certain extent, these materials may appeal to businesses, contractors and homeowners. As they have low or even zero-embodied energy, there is proof of increased sustainability and energy efficiency when compared to traditional materials,” says Anthimos Pavlidis, a civil engineer and quality coordinator in the project of the skyscraper centre One Blackfriars, London.
Financial profit can be identified from manufacture through to impact across the operational life-cycle of buildings. “Nevertheless, a rationalised piece of legislation is needed in order to woo manufacturers and contractors. Integrated policy measures including incentive schemes and training seminars have to be implemented in order to achieve widespread use of biomaterials,” Pavlidis tells youris.com.
As for construction companies, they are smelling the business opportunities. “These companies – particularly those in the green building sector – aren’t going to wait for their national governments; they are simply going to act on climate change because they know it makes good business sense,” says Wills, “There is no longer any question of whether or not to decarbonise. In our opinion, this is the greatest triumph of the COP21″.
Innovation in the construction industry will play an important role in reducing emissions and improving energy efficiency —though developing new materials and methods is only half the battle. Convincing architects and homeowners of the performance and long-term financial benefits of a new product presents a significant challenge.
By contrast, bio-based insulation typically have much lower “embodied energy” levels compared with more conventional building materials. Furthermore, the source materials themselves sequester atmospheric carbon dioxide via photosynthesis.
“The beauty of bio-based materials is that they are often a byproduct of growing our food. We can build with carbon. Instead of seeing carbon as a problem, we can recast our relationship with it to one of positive innovation”, says Craig White, director of ModCell, which produces straw-bale eco-homes.
The company is one of the 12 partners in academia, research and industry that are collaborating with the European project ISOBIO. It aims to deliver bio-based insulators with 20% better performance than conventional materials, leading to a 5% total energy reduction over the lifecycle of a building at reduced costs of 15%.
Producers of bio-based insulators have the advantage that users are both receptive to change and familiar with the products in some capacity. In a study conducted by the Architects’ Council Europe (ACE) for the Low Embodied Energy Insulation Materials (LEEMA) project, 94% of architects surveyed said they would consider using a new and innovative insulation material. An overwhelming endorsement for what remains a niche application in the construction and renovation industries.
Renovations present a key market for producers of new insulation materials. According to the Buildings Performance Institute Europe (BPIE), more than 40% of Europe’s existing homes were built before the 1960s, when there were few requirements for energy efficiency, leading to low insulation levels.
Increasing awareness of the importance of insulation among homeowners is an important consideration. Homeowners may be inclined to, for example, upgrade appliances and install energy saving light bulbs, unaware that retrofitting wall and roof insulation leads to the greatest savings opportunities.
Veronika Schröpfer, lead author on the ACE survey, believes that bio-based insulation materials will continue to move from the niche into the mainstream and that new skill requirements will not present significant roadblocks.
Schröpfer says new building materials are often applied the same way as commonly used ones and manufacturers usually offer training when this is not the case. She states the main concerns involve pricing and regulations in different European countries.
“For architects it is important that a new material has all the necessary certificates and that the product information is transparent, to quickly compare its performance and price with traditional products,” says Schröpfer.
White believes that developers will be receptive to change. “The challenge that ISOBIO will overcome will be to bring [products] to market at scale at the price point that matches their performance to market demand,” he says.
Europe’s construction industry has experienced a turnaround over the last two years. After registering negative growth in 2013, the industry grew by 2.1% this year, and is forecast to grow by a further 2% over the next five years.
Evidence suggests that a growing minority of these builds will involve green projects. A market report from the Word Green Building Council states the proportion of architects and engineers that dedicate 60% or more of their project load to sustainable builds more than doubled over a four-year period — from 13% in 2009 to 28% in 2013.
The report states that increasingly, industry consumers not only demand that new innovations improve performance, but also reduce environmental impact. Fertile territory for the right nature-inspired solutions.
By Angus McNeice
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