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  • HPH355: The Story of Upfront Carbon – with Lloyd Alter

    HPH355: The Story of Upfront Carbon – with Lloyd Alter

    Lloyd Alter explains the term upfront carbon, its relevance to us all as consumers, and why he felt compelled to write a book on the topic.

    Interview with Lloyd Alter

    In 2021, Lloyd released his book Living the 1.5 Degree Lifestyle, where he attempted to limit his carbon emissions in line with what climate scientists say would be needed to keep within 1.5 degrees of global warming. Lloyd took on this challenge just as the Covid-19 pandemic struck and therefore it might have been slightly easier than normal because big emission activities such as flying were restricted. After completing a year living within this carbon budget, Lloyd stopped carbon counting. Habits that stuck include eating more vegetarian meals each week, using his e-bike instead of his car as much as possible, and not buying gadgets on a whim. The trickiest part for him has been air travel and he has taken a few flights since.

    After examining the power of our personal choices Lloyd’s latest release focuses on our obsession with stuff! In his new book, The Story of Upfront Carbon: How a Life of Just Enough Offers a Way Out of the Climate Crisis, Lloyd explores the carbon emissions linked to everything we purchase as consumers.

    “If you buy a car you’re buying 14 tonnes of upfront carbon emissions, the emissions of making that car. Everything you buy has these issues and people would talk about efficiency, efficiency, efficiency. But efficiency is pointless without sufficiency.”

    What is upfront carbon?

    When it comes to producing products a common phrase used to describe carbon emissions (or greenhouse gas equivalent emissions) is ’embodied carbon’. However, the word embodied is misleading in this context as it seems like it is describing a positive process of carbon sequestration rather than a harmful process of emissions. Lloyd, alongside Elrond Burrell and Jorg Chapa started thinking if it could be described more accurately and came up with ‘upfront carbon’. This term clearly highlights to the consumer what the carbon cost has been to create a product up until the point of purchase.

    Upfront carbon refers to the first 5 stages of the life cycle (production and construction) from A1 to A5 which goes from the mining of materials right up to the use stage. It can be difficult to find accurate information within different aspects of the supply chain which makes most calculations an estimate rather than a certainty. Lloyd highlights that in spite of this uncertainty, it is always a good idea to use as little resources as possible as this will reduce the upfront carbon. It is also important to focus on items that use less processed materials because the upfront carbon will be significantly lower, so a wooden pencil rather than a metal mechanical one, or straw insulation over foam.

    “The ultimate thing is just how much of everything are we using”

    Upfront carbon is a good place to start but can’t be the end

    Upfront carbon tells us a story about the production process of that object and can highlight the impact that the mere existence of the product has on our planet. However, with many of the things we buy, we will also generate carbon emissions when we use or maintain them. The easiest example of this is a car, which comes with approximately 14 tonnes of upfront carbon, but if that car has a petrol engine with poor fuel efficiency, the carbon emissions will be ongoing. It is therefore important to be looking at both the upfront carbon and the entire lifecycle of the product, in order to understand its impact and determine whether it is worth purchasing in the first place and how best to manage it.

    “I had a student who actually analysed a pencil for her class. It was a brilliant, brilliant examination because the Staedtler pencil was made in Nuremberg, from clay from Pennsylvania and graphite from Turkey and cedar from California. And all of these things came together in a pencil in Nuremberg, which was shipped to the store in Aurora, Ontario, North of Toronto. But the carbon emissions from her driving to the store and bringing it home were twice as big as the whole manufacture of the pencil and shipping everything all over the world.”

    Buy good quality things and maintain them for as long as possible

    Every time you buy something new it comes with upfront carbon. Every year you can make that product last, you are amortising that upfront carbon over a longer period and it will be getting less and less. Lloyd highlights this as the simplest method for reducing your carbon emissions and by breaking that consumerist mindset, you will be taking a large step towards a more sustainable lifestyle.

    Use materials that have been processed less

    Lloyd highlights that another way to ensure you are reducing your upfront carbon is to use natural materials where possible. The majority of building products that have been highly processed will have extremely high upfront carbon, items like foam insulation or concrete. Lloyd uses an example from Steve Webb:

    “He said, how do you make concrete? You take limestone, you grind it up into a powder, you put it in a kiln at 1450°C. You then mix it with a bit of clay and aggregate to make what is basically artificial stone. So if I go to a quarry, cut out the limestone, cut it into blocks, drill a hole and put a cable through it as reinforcement, I can make a beam out of stone that is stronger than the beam out of concrete with a 10th of the upfront carbon emissions and it will last five times as long. I said why aren’t we doing this? Making concrete is perverse.”

    Constructing Old Holloway with EcoCocon panels

    Simpler designs will use less

    Minimally processed materials must be used in the most efficient way and all while keeping a check on the scale of things. Lloyd indicates that there is often a misconception that if wood sequesters carbon, then using as much as possible can only be a good thing. However, this negates the fact that wood is a precious resource and whilst it is a great natural building material with low upfront carbon, it should be used as efficiently as possible within the structure.

    While much of the design world ignores the wisdom of optimising, the path is clear. For example, for larger timber buildings they would be simple and boxy, and limited in height to around 6 storeys. The buildings would have flat facades and fairly small windows.

    “We should stop this insane competition to be the tallest wood building in the world. You don’t want to be the tallest wood building, because then the columns are getting bigger and bigger and bigger, and you’re putting in more and more fibre. And you’ve got to deal with harder fire regulations and all of these things.”

    Finding out accurate information about the upfront carbon can be difficult

    You cannot accurately measure the upfront carbon of wood because every tree is different and unique. The most important thing you can do is make sure you only use FSC certified timber.

    Both high energy efficiency and low upfront carbon must be prioritised

    The construction space can be filled with confusing examples. Many of the first really efficient houses used foam insulations with huge amounts of upfront carbon, so whilst carbon emissions were reduced on a day to day basis, they were significant during construction. An opposing argument has been raised from within the eco build community, where natural building materials with low upfront carbon have been prioritised whilst the need for energy efficiency has been questioned. Lloyd believes that both must be considered equally to ensure that our homes are as sustainable as possible whilst also providing comfort and security.

    There may be emissions from heat pumps

    The refrigerants used in heat pumps often contain harmful greenhouse gases and so if the heat pump isn’t installed correctly they may leak. There are now some heat pumps that claim to use ‘natural’ refrigerants but in reality they are still fossil fuels, just natural gasses rather than fluorocarbons. The ‘natural’ heat pump is a much less harmful version and should definitely be prioritised where possible, but it is not necessarily emission free. Because of this nuance, once again, it is important that the spaces we are designing are modest to ensure that we can keep the size of our heat pump down and therefore reduce the associated emissions.

    Copyright by Evelyne Bouchard

    We need to design with grid intermittency in mind

    Lloyd highlights that there is a growing need to design buildings with future grid intermittency in mind. This would include low carbon, well insulated and efficient shells in order to maintain indoor temperature in the possibility of power cuts. With a need to move towards more and more renewable energy sources, it is important that we anticipate the potential issues that could arise and plan around them. Lloyd highlighted a potential to connect up car batteries to houses in order to utilise each of our resources to the max.

    “The thing about this new world we’re getting into where we’re relying on renewables for everything is that renewables are intermittent… We have to design our houses to be really, really efficient so that if the heat goes off for an hour, and the hot water heater goes off, you don’t notice it.”

    Cultural shifts can cause a ripple effect that increases our carbon emissions

    Lloyd uses the example of the hamburger as a cultural ripple effect. The rise of fast food and drive thrus has created a culture around eating inside our cars. As a result car manufacturers began to add in features such as tray tables and cup holders to make this experience easier for the consumer. As years go by, these features increase and the overall size of cars increase too as a response to the amount of time we are spending in them. All of these increases go far beyond sufficiency and enter the world of excess, where every extra feature and every extra inch of space is adding to the upfront carbon of the car. This is a great example of how our cultural and consumerist influences cause these ripple effects that amplify our impact on the climate at every stage.

    Copyright Looney Tunes

    ‘Visualising’ the carbon may help us grasp its impact

    Lloyd spent a long time deciding on the best metric of measuring upfront carbon and eventually settled on Wile E. Coyote’s biggest threat, an anvil. It can be difficult to grasp the real impact of upfront carbon when it is measured in pounds or kilograms. Therefore being able to say that the production of a Macbook Air took an anvil and a half of carbon or that a watch was half an anvil can be a really valuable image to help people understand the true impacts of their possessions.

    Could a ‘carbon allowance’ be the answer to sufficiency?

    Lloyd suggests that carbon rationing could be a good strategy to help reduce carbon emissions. Everyone would be allowed the same, whether that’s by year or by lifetime, and from there they are free to decide what to spend their allowance on. The idea is that the consumer would be encouraged to reflect on the impacts of the products they buy and the choices they make.

    “So if you’re building lower cost housing, you could maybe say slightly lower standard because it’s small. But if someone wants to build 500 square metres and has the same carbon allowance, they’re going to have to really be careful and they’re going to have to build it to a really high standard. And then if you start saying oh, by the way, you’re only allowed to have this much carbon allowance to build your whole house. Well, then they’re suddenly going to be looking at saying the only way I can build my mansion is if I build it out of straw and hemp on woodpile foundations.”

    Sufficiency, sufficiency, sufficiency: how much do you really need?

    “In this new world of upfront carbon, we have to turn that on its head and start thinking about sufficiency. How much do we need? And this goes through everything. How much clothing do I need? How much food should I be buying? How big is my car? Do I need a car? How big is my house? Everything we do we should look at it. And I often say when you look at the world through the lens of upfront carbon, everything changes. You just start thinking differently about everything you do and everything you buy.”

    Find out more

    Get your copy of The Story of Upfront Carbon

    Living the 1.5 Degree Lifestyle

    Key decisions that impact on the sustainability of a house build

    Worldwide trends in green design

    Transcript

    Download the transcript of this episode.

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  • HPH273 : A hemp house that also minimises plastic use – with Paloma Gormley

    HPH273 : A hemp house that also minimises plastic use – with Paloma Gormley

    Architect Paloma Gormley of Practice Architecture explains how versatile hemp can be as a building material, and how plastic use can be reduced on site.

    Copyright David Grandorge

    Interview with Paloma Gormley

    Paloma and Lettice Drake’s Practice Architecture made their name when they were approached to design a roof-top cafe above a car park while in the third year of their architecture degree. Not knowing where to start with appointing a contractor, they decided to build it themselves. From being incredibly inexperienced and using power tools they’d bought from a supermarket, they successfully constructed “Frank’s Cafe” which became an incredibly popular venue.

    Frank’s Cafe and Campari Bar, Peckham. Paloma Gormley and Lettice Drake
    Image Credit Andy Matthews

    Being closely involved with the construction process is a theme which has continued throughout their approach to architecture.

    Hemp is a versatile plant

    Industrial hemp is a plant within the cannabis family that has very low THC – the psychoactive element of the plant. It’s legal to grow in the UK with a licence and has a multitude of uses, with the fibre being used in rope and linen, the seed which has nutritional value, the bud which can be used medicinally, and the shiv which is the stalk of the plant that can be combined with clay to form hempcrete.

    Hemp also sequesters carbon more than most other plants. As it’s growing it sequesters carbon into the body of the plant and also into the soil.

    Paloma’s interest in using it as a building material began with a friend’s group, Hempen, that had set up a hemp farm in Oxfordshire. The friend had suggested using hempcrete as a building material for a three-storey London self build house they were working on, and it turned out to be a very practical material for the design. It was cast in-situ and infilled between a Douglas Fir frame.

    Image Credit Oskar Proctor
    Image Credit Lettice Drake
    Image Credit Oskar Proctor
    Image Credit Lettice Drake

    Drying time issues can be overcome by using pre-fabricated cassettes

    Paloma agrees that there can be an issue with drying and curing times when using hempcrete, depending on the binder that is being used. Some of the more reliable binders have a cement content, which isn’t ideal, but those that are pure lime can be more tricky to use as they can set too fast or slow or don’t hold.

    While it can set in 24-48 hours depending on the binder, the drying times can be incredibly long. They can average at around three months for the building to completely dry out depending on temperature and air flows, meaning secondary finishes can’t be applied during this time.

    Another limiting factor can be that it is not ideal to be casting hempcrete on-site during the winter period. There’s a risk that there can be too much dampness in the wall for too long before it has a chance to dry out, causing all kinds of problems.

    One solution is to take the wet process off-site. This means the drying can take place somewhere else and then delivered to site as dry cassettes ready to use. The benefits are a more streamlined construction process, with it being cleaner, less complicated, no time spent waiting about and all twelve months being available for building.

    Hempcrete Cassettes – Image Credit Paloma Gormley
    Image Credit Paloma Gormley

    Hemp is being used innovatively at Flat House, Margent Farm

    Margent Farm in Cambridgeshire are an organisation that are growing a 40 acre hemp farm. They carry out R&D and are developing a number of hemp-based bio alternatives to plastic products.

    The brief for the farmhouse on the site was that it needed to have a good connection with the landscape, have very low embodied carbon and to avoid plastic use wherever possible.

    Plastic in its various forms is prevalent even on buildings with high ecological credentials, being used as polyurethane rigid foam insulation, vapour barriers, sticky tapes, expanding foam, nylon thermal bricks and gaskets. It can also be other things invisible to the eye such as the wiring, ducting, pipes and vents.

    Hemp cladding has been used

    It wasn’t possible to achieve the elimination of plastic completely, because of barriers in terms of cost and also in terms of alternative products just don’t exist. But overall, Paloma said they did pretty well.

    They achieved it partly by returning to what is known as breathing construction. This takes moisture from the air inside a room, absorbs it into a wall and then breathes it out the other side.

    “There are many reasons why that’s a really good thing. It limits condensation, you can have a self-regulating moisture content in a room because if the moisture content in a space gets too high, it just gets pulled into the walls and then evacuated, and it means that when something goes wrong, you know it’s gone wrong because breathing construction generally involves a much more direct relationship of material.”

    Achieving a high level of airtightness hasn’t been a key concern on this project. The main priority has been to make a well thermally insulated, incredibly low embodied carbon building.

    “So, you always have to have a level of background ventilation which we used to achieve by just having slightly leaky buildings. Now we’re making incredibly airtight buildings and then making intentional holes, which I think is a funny logic in a way, because so much generally plastic goes into making incredibly airtight buildings and then we’re punching holes in them.”

    One of the products developed from the crop at Margent Farm is the cladding that they are using on the farmhouse. It is a hemp fibre with a sugar based resin derived from agricultural waste. They are combined, pressed together and baked in a heat moulding process.

    Image Credit Paloma Gormley

    The circular economy is informing design

    Cost concerns meant that aluminium windows were chosen over timber, and although it is a very high embodied energy material, the way it can be recycled means it fits in well with a circular economy way of thinking.

    Getting the foundations right was one of the biggest challenges on the project, and they opted for concrete foundations with a suspended timber joisted floor. Since then, they have been thinking of alternative options for future projects. One possibility would be screw piles, which are dependent on the type of soil you have and can’t be used in every situation. The thinking here is again about the circular economy, where these could be unscrewed and used on another project in the future.

    Another option they’re excited by is compacted hardcore such as flint or stone which could be sourced very locally.

    A cassette system was used for the walls, based around an eight by four sheet made in a factory as boxes, filled with hempcrete and dried. They were brought to site and erected within two days.

    Image Credit Paloma Gormley

    The roof was a straight forward joisted construction, with a wood fibre insulation.

    Image Credit Paloma Gormley
    Image Credit Paloma Gormley
    Image Credit Oskar Proctor
    Image Credit Oskar Proctor
    Image Credit Oskar Proctor
    Image Credit Oskar Proctor

    The Flat House led to the establishment of Material Cultures

    Material Cultures is a not-for-profit organisation that explicitly researches and explores these different materials in the realm of off-site construction. The aim is to make them more accessible, available and affordable. They are looking to start manufacturing at a larger scale, drawing on the model of the Flat House.

    Material Cultures are also working on research projects with two universities and are developing another prototypical building with architecture students at University of the Arts London, all feeding in to the broader research.

    “So, it feels very important to us that this project and these processes happen in a very reflective way, that we’re constantly learning and moving and developing thinking.”

    Find out more

    Visit the website of Practice Architecture

    Check out Practice Architecture on Instagram

    Find out more about the work of Material Cultures

    Learn more about the uses of hemp from Hempen’s website

    Transcript

    Download a transcript of the interview with Paloma-Gormley.

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  • HPH263 :A step-by-step EnerPHit retrofit of a mid-terrace home – with Harry Paticas from Arboreal Architecture

    HPH263 :A step-by-step EnerPHit retrofit of a mid-terrace home – with Harry Paticas from Arboreal Architecture

    Harry Paticas of Arboreal Architecture explains why care and hard work have been so important to the retrofit of his 1978 mid-terrace townhouse.

    © Agnese Sanvito

    Interview with Harry Paticas

    Harry has a background in art and maths, which he then followed with a degree in architecture. He says the turning point in his twelve years in practice as Arboreal Architecture was taking the Passivhaus training course and suddenly being able to understand how buildings perform.

    Together with his interest in building performance and the natural world, he also has a passion for retrofit, and is currently getting towards the halfway point of a phased retrofit of his own house, a project which was overall winner at the inaugural ASBP Awards 2019.

    “When you put passion in, you get something out”

    The house was purchased in 2016 with the aim of doing a retrofit project. Although they had intended on finding something a bit cheaper so they would have more money to spend on the works, this house cost rather more than they had budgeted for which is the reason they are not currently as far along as they had hoped.

    It is a south facing, slightly staggered mid-terrace property. It is a combination of a solid brick and block front wall that is tile clad, while the back wall is brick both sides with a cavity.

    © Agnese Sanvito

    It has been an intensive couple of years working on the house, with every Sunday taken up by long hours of DIY. It has been a massive learning journey which Harry says has also been of benefit professionally.

    Not only has the DIY element of the project been hugely rewarding, but it works in parallel with his professional role where he can now speak even more confidently and knowledgeably to clients. This could be about how the MVHR functions, how often you need to change the filters, how the pipes connect etc. Likewise, it aids with speaking to builders and helping them do a better job, which gains more respect from them in turn.

    The strategy involves four phases

    The first phase involved work being carried out before they moved in. They had sold a property and were renting so that they could get any of the dangerous, dusty and cold work out of the way while living in their rental accommodation. This included asbestos removal from ceilings, airtightness works to the ceiling on the top floor, putting in and taping vapour block boards to each other and to the walls, adding insulation to the loft, making the house secure and weathertight and installing three triple glazed windows.

    Generally the plan has been to work from the top of the house down to the bottom. Following the loft works and triple glazing to the front elevation they added insulation to the walls of those rooms. By this time they were living in the house and noticeably felt the thermal shift during the winter weekend when they added the cork insulation to the walls.

    A key part of the strategy was maintaining good quality ventilation before the MVHR unit was even installed. With the existing leaky double glazing they knew it wouldn’t be a problem, but when they were replaced with the triple glazing they specified night vents. These allow the handle to be put to 45 degrees off the vertical which gives a 3mm opening in the window at the top. This meant they could maintain decent air quality as an interim measure without the need for installing trickle vents.

    By doing lots of monitoring of particulate matter, nitrous oxide, carbon dioxide, temperature and moisture content, they could use the information to decide whether night vents should be open or not.

    Harry is currently finishing off bits of airtightness work and interior decorating of phase two before working on the next big phase which will be working out where the living space is going to be. The plans they submitted to the Passivhaus Institute had it on the first floor, but they’re now thinking of having it on the ground floor.

    © Agnese Sanvito

    According to their EnerPHit retrofit plan, the next phase is to temporarily insulate the garage door. This will instantly reduce heat loss through the whole of the living room floor, the ground floor hallway and a back wall of the garage. In order to do that they will need to block the door and create a new entrance into the garage.

    Along with insulating the porch and insulation to the bathroom, these will form phase three, with phase four being the ground floor front and back insulation, and insulation to the floor.

    Cork has been used for internal insulation

    Harry was always going to use an insulation material that was from renewable sources. He also wanted something that wouldn’t off-gas but be neutral in terms of air quality.

    His work with Jane Anderson on embodied and sequestered energy in a range of insulation materials has shown that cork actually has lower embodied energy than wood fibre, and is very good on both counts.

    It hasn’t performed as well as hoped in the heat

    While internal temperatures have reached 27 degrees, it hasn’t overheated in the Passivhaus terms of over 20 degrees for 10% of the year. With the new windows they are getting 20% less sun through, but with the cork they’re not getting much effect from decrement delay. They have a medium thermal mass and the top floor doesn’t cool down very quickly because of the blockwork walls and brick party walls.

    Currently being made are three bright yellow sails which can be attached to the front of the house and shade 100% of the top two windows and over 50% of the large living room window. They will provide a low carbon, low tech solution to shading and reducing overheating, and which can be packed away in a bag in the loft when not needed for the rest of the year. They will also be able to judge their effectiveness scientifically as they have installed sensors on the inside and outside of various rooms of both theirs, and their neighbour’s house for comparison.

    It’s also about respecting materials that are already in the building

    The process they have adopted has been to try not to replace something if it actually works quite well.

    “So there’s a little bit more of a lean towards embodied carbon, rather than very demanding interior design aesthetics.”

    This has led to what Harry calls some ‘fun moments’ and to a little bit of variation, which they’re accepting of and saying that’s what this is about, rather than trying to put his architectural stamp on everything and making it as perfect as possible.

    It has been an education for his son

    With Harry’s son soon turning eight, he was keen for him to be involved and remember the experience as much as possible, with a deep understanding of what it is they were doing and why.

    With only a little encouragement at first, his son has been producing a series of A3 posters with images, annotations and diagrams, about cork, airtightness, a thermographic survey, insulation and mechanical ventilation with heat recovery.

    © Agnese Sanvito

    His teacher engaged with the process and has encouraged him to display them in school and do presentations about them to his class.

    A direct result of the school presentations is that Harry is starting a charity or community interest company which will be about retrofitting schools. He will be delivering thermal performance workshops to school children and doing research with them where they look at the fabric of their classrooms and the school and coming up with a retrofit masterplan.

    There have been particularly pleasing elements

    Having never had them before, Harry particularly loves the triple glazed windows, which is an opinion shared by visitors to the house. They are inward opening with a central flying mullion which allows them to open up a whole elevation and achieve very rapid night time cooling.

    © Agnese Sanvito

    Another favourite feature is the MVHR unit. They still open windows when they want, but for general air quality which has been backed up with numerical evidence from their monitoring, it has been particularly pleasing.

    © Agnese Sanvito

    Harry says that working with and getting to know materials has also been lots of fun, particularly with the cork.

    Find out more

    Visit the website of Arboreal Architecture

    Follow Harry Paticas on Twitter

    Support Harry’s petition for zero rate VAT on deep retrofit

    Transcript

    Download a transcript of the interview with Harry Paticas

    Please connect with me

    Subscribe, rate and review the podcast in iTunes

    Rate and review the podcast on Stitcher

    Like our Facebook page

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  • HPH092 : Is Hempcrete a Good Material for Ecological Buildings? – with Professor Tom Woolley

    HPH092 : Is Hempcrete a Good Material for Ecological Buildings? – with Professor Tom Woolley

    Professor Tom Woolley from Rachel Bevan Architects explains what hempcrete is, how it is mixed and applied, and what the pros and cons of using it are.

    Tom Woolley

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