It is difficult to find people who do not like trees. Trees have cheerleaders across the social classes; young and old, rich and poor, left and right. There is a vocal minority who believe that trees should be left well alone. What, they ask, is the environmental gain of chopping them down and bringing them out of the forest? Well, the answer is that when it comes to tackling climate change our forests are only half the story – and hence only half the answer. We can build with wood, wood that stores carbon and substitutes for much more carbon-intensive building materials. Without doubt wood is special. As one of the champions of building with wood, Vancouver-based architect Michael Green, has put it: “Wood is the most technologically advanced material I can build with. It just happens to be that Mother Nature holds the patent on it and we are not comfortable with that. But that's the way it should be: nature's fingerprints in the built environment”.

We have been building houses from wood for thousands of years. Most European cities still have a few timber-framed buildings dating back 300 years or more. York in the UK is a good example. Here you will find The Shambles – a street of medieval timber-framed buildings with a strong Harry Potter feel to them. Strasbourg, home of one of the two seats of the European Parliament – and somewhere I travelled to every month for five years as an MEP – has some fine examples of old timber-framed buildings (Figure 2.1). Some of these were carefully rebuilt after the Second World War but to the untrained eye look as old as those that were not damaged.

When these buildings were erected, they had only one purpose – that of providing shelter, a home. However, although unknown at the time, they were also safely storing the carbon that the timber had sequestrated (soaked up) when it was growing as a tree in the forest.

Let us recap. The climate crisis we face necessitates two vital responses that are both equally critical and need to be enacted in tandem: an end to nearly all greenhouse gas emissions including CO2 into the atmosphere and the removal from the atmosphere of existing greenhouse gases including CO2. A major contribution to the first of these tasks can be achieved by substituting the numerous carbon-intensive materials that we currently use in our built environment, including concrete, steel, plaster board, plastic, brick and block, and replacing them with timber-based products that store carbon (see Chapters 1–4). The second task can be tackled in part by planting trees in as many settings and configurations as possible. This will involve improving our sustainable forest management techniques, extending our existing forest cover as and where appropriate, moving closer to harvesting the net annual increment across all European countries (see Chapter 7) and redeploying abandoned farmland for afforestation (see Chapter 9). Together, these steps will increase the amount of CO2 that is sequestered.

Having increased our tree cover we also need to increase our use of timber as this demand is key to driving the “forest pump”, which we discussed in Chapter 2. Ideally as much timber should go into long-life harvested construction materials as possible so that we can store as much carbon as possible in the built environment and reduce the use of carbon-intensive materials. The felled trees are then replaced with new growth enabling the “forest pump” to continue its vital work of sequestering more carbon and then moving it via the timber to be stored in the built environment.

As George Orwell noted, “To see what is in front of one's nose needs a constant struggle”, hence it is not surprising that although timber offers a significant solution to climate change very few people realize this. As I have argued, timber is the material we must use to replace our main carbon-intensive construction materials, especially concrete and steel. It can both substitute for these materials and safely store carbon. To help us understand timber, and why it has such potential to help us, we should visit the forest. This book is pro-timber, but also very much pro-forest.

Almost a third of the world's land surface is covered by forests. Europe's forest cover is 35 per cent – over a third of the continent. UK forest cover stands at 13 per cent. Within the EU Finland (74 per cent of total land area) and Sweden (69 per cent) are the most heavily forested countries, followed by Slovenia (61 per cent), Estonia (57 per cent) and Latvia (55 per cent). The Netherlands (11 per cent), Ireland (11 per cent) and Malta (1 per cent) are the least forested countries. If we consider things at a European level – which brings in the Russian Federation, Norway, Switzerland, Ukraine, Belarus, etc. – then forest cover is around 1,000 million hectares, which is about 30 times the size of Poland (see Figure 6.1). The largest forest area in this wider geography is located in the Russian Federation.

All trees – big or small, deciduous or coniferous, on their own or with other trees in a forest – have the ability to absorb carbon dioxide (CO2) from the atmosphere and exhale oxygen in return, which is why forests are often rightly referred to as “the lungs of the earth”. However, as Harald Mauser of the European Forest Institute points out, “This is reversed when trees are dead and decay. This releases almost all the CO2 they stored except a very small part that was transferred to the soil via litter and roots”.

As the apartheid regime in South Africa entered its death throes the octogenarian president of the British Anti-Apartheid Movement (AAM), Archbishop Trevor Huddleston, became increasingly worried that he would die before Mandela was freed, apartheid was vanquished and a new democratic South Africa was born via the ballot box. He therefore took to haranguing, and only in a semi-friendly way, the staff of the AAM when he visited us at the movement's headquarters in an old piano workshop in Mandela Street, Camden, London. To help reinforce his key message that we all needed to work harder he always told us the same, short, humorous tale. On a “recent” visit to his spiritual home – the College of the Resurrection at Mirfield near Leeds – he recounted that over breakfast he and his fellow octogenarians had fallen into a conversation about the pros and cons of buying a new suit at such an advanced age, whereupon the oldest member of the community, who was in his nineties, piped up “New suit? New suit? I worry about buying green bananas”.

When it comes to climate breakdown we are without question in “green banana” territory. There really is very little time left. In the words of Antonio Guterres, the Secretary General of the United Nations, “Climate change is here. It is terrifying. And it is just the beginning. It is still possible to limit global temperature rise to 1.5°C and avoid the very worst of climate change. But only with dramatic, immediate climate action”.

I was lost. Hopelessly lost. Getting lost was an occupational hazard for a new Member of the European Parliament (MEP). The parliament building in Brussels is enormous. But help was at hand in the form of Frank Schwalba-Hoth, a former German Green MEP. He looked kind and was wearing a bowtie.

“Where are you trying to get to?” he asked.

I gave him the number of the committee room. “Right”, he declared,

“Follow me!” It was a fair walk and as we proceeded, “Have you decided?”, he asked.

“Um, decided what?”

“Decided on your focus. You can't do everything. When you walk through parliament, you need people to point and say: ‘That's Paul Brannen MEP. He's the Mother Teresa of … windfarms’, or something along those lines”.

We arrived at the committee room and with a shake of hands he was off.

It was a year before I saw him again. As it happens, it was at a climate change event I was speaking at, in the Chapelle pour l’Europe in Brussels. Herr Schwalba-Hoth was the chair. At the end, over a glass of Cabernet in the crypt, I asked him if he remembered our first meeting.

“Oh indeed”.

“So, what am I the Mother Teresa of?”

“You, Paul, are the Mother Teresa of trees”.

I’ve always had a few issues with Mother Teresa, so I mentally translated this into “the Martin Luther King of trees” which fitted in better with my theology.

From then on I was determined to become if not an expert at least reasonably well informed on trees, timber and their climate benefits (as opposed to becoming an elderly Albanian nun). Before long I was sitting on the European Parliament's Agriculture and Environment committees, focusing on forestry and on using more wood in buildings and the built environment.

Then Brexit struck. I was now a political Dodo. A “former British MEP”. But, thanks to Herr Schwalba-Hoth I departed the Parliament with a niche understanding of European wood products and their potential to help decarbonize the built environment.

Using more wood in construction and renovation to turn our built environment from a climate problem into a climate solution is predicated on there being enough wood and wood fibre to do this.

First and foremost, this supply of wood has to be sustainable. For our timber supplies to be deemed sustainable the wood must be sourced from a managed forest where natural regeneration of the forest is viable or where new trees are planted as others are felled. Such replanting needs to see between 5,000‒10,000 saplings planted per hectare, replacing around 500 felled trees per hectare. The forest ecosystem is required to be regularly monitored to ensure it remains in good health and able to provide for both people (employment, recreation) and nature (biodiversity) now and into the future. A certification scheme accompanies this process of which more than 50 exist worldwide. Of these, the Forest Stewardship Council (FSC) and the Programme for the Endorsement of Forest Certification (PEFC) are the two best known. While both schemes are committed to the same cause – sustainable forestry – the primary difference between the certifications is their origins. Initially the FSC scheme was developed for tropical environments and not suited for forests in Europe and North America. This led to the introduction of PEFC in the late 1990s to facilitate sustainable forest management (SFM) certification in Europe. PEFC now accounts for over 264 million hectares of certified forests, 10 per cent of the world's forest area, and its certification system is recognized in over 30 countries. Meanwhile FSC has certified forests in over 80 countries with 7 per cent of the world's forest area (180 million hectares) carrying the FSC certification. Fifty per cent of people in the UK recognize the FSC logo in relation to buying wood products.

This is an optimistic book, but it starts from a challenging place.

In 2020 the global population was approximately 8 billion. By 2050 it will likely hit 10 billion. The additional 2 billion people will all have something in common: they will need somewhere to live. The majority of these 2 billion people will be in the Global South, in urban areas, and will be housed in high-density, high-rise buildings. They will need to cool their homes, mainly flats, not heat them. So next time someone tells you we need to build less, not more, ask them where they expect the 2 billion to live. Population growth may be flatlining in many European countries, raising for them the valid question: Do we really need to build more homes? But in the countries of the Global South, and in countries like the UK, USA and Canada, the population continues to rise – and we all need somewhere to live. It is this increasing demand for housing that puts humanity in such a challenging place. This population growth will create further massive demand for new buildings and the production of cement, steel and other building materials associated with this wave of construction will become a major source of greenhouse gas emissions (GHG).

To meet this construction demand the world will need to add 190 billion m2 of new buildings every decade for the next 40 years, which is equivalent to adding a London-sized city to the planet every 70 days. The challenge, as defined by carbon finance company Aureus Earth, is that, “Without intervention, business-as-usual construction would alone consume 60% of the remaining global carbon budget (500GtCO2e) if humanity is to limit global temperature rise to 1.5°C”.

How we build, renovate, heat and cool our built environment has become the biggest cause of climate breakdown and is the central problem addressed in this book.

In Chapter 7 we identified that the expanding bioeconomy, which includes using more timber to decarbonize the built environment, is going to demand larger and larger amounts of sustainable wood and wood fibre in the years ahead. We concluded that additional sources of supply, over and above those identified in Chapter 7, would need to be found. In this chapter we examine one specific way in which we can deliver a significant increase in sustainable wood supply: by growing more wood on farms.

We first need to remind ourselves that wood comes in all shapes and sizes, or to be more precise, the demand is for different sorts of wood for different uses. To build more timber-framed houses and to erect more big buildings made from engineered timber we will need an increase in the supply of traditional timber, i.e. long strips of cut wood. In future, as today, the vast majority of this kind of wood will be sourced from the forest. We will also need more woodchips to make wood panels and wood fibre to make insulation. Both of these products can be made from tall “straight” trees grown in the forest but they could be made from smaller trees that are not as straight grown on farms. Similarly, wood for energy can be sourced from the forest but could also be sourced from the farm. In the same way, the wider bioeconomy can take its wood fibre from the forest but could – in most cases – take if from the farm.

Let us begin by focusing specifically on meeting the growing demand for wood for energy, often referred to as biomass. Biomass is simply organic matter used as a fuel and it can be supplied by crops such as willow, Eucalyptus, Miscanthus (a large, woody plant from the grass family), hemp, straw and maize. As we have seen in the previous chapter this demand is set to grow. As this wood for energy demand increases we need to ensure that there are no future conflicts of demand. We must avoid competition over the supply of wood between wood for the energy sector on the one hand and wood for the construction sector on the other.

Loft insulation may seem an odd subject for a call to arms. But your loft, possibly your least exciting room, is critical to tackling climate change. That is because efficient insulation helps us use considerably less energy heating homes, which in turn means less fossil fuels will be burnt. But your current insulation material, if you have any, will most probably have both contributed to climate change as well as help prevent it.

The market for building insulation is already huge, worth ￡1.38 billion in the UK alone, and it will become even bigger as we endeavour to achieve net zero emissions from the built environment by 2050. This is because both the UK and the EU are way behind targets for retrofitting existing building stock with a high standard of insulation. Additionally, in most cases, our new builds also fall well short of the level of insulation necessary to help us achieve net zero and will themselves need to be (expensively) retrofitted with better insulation.

Most household energy use goes on heating our homes during the colder months (see Table 3.1). The quickest, most effective and cheapest way of reducing this consumption of energy is to better insulate our homes. That means the warm air we have expensively created for ourselves does not simply leak away, creating a need for yet more warm air, which means burning yet more gas, oil or coal. Our homes are no different to our bodies. Feeling cold? Put a jumper on. House feeling cold? Insulate your loft and walls. Homes in the UK are on average older than homes in the rest of Europe and therefore tend to have poorer insulation. So, they need more heating and use more energy. Shockingly it is not only old homes that are badly insulated. New homes are as well.

In the last chapter, we explored how boosting the growth of wood fibre could provide us with the quantities required to significantly increase the use of wood in the built environment and the growing bioeconomy. This would involve wood fibre produced on European farms, in addition to that already grown in the forest. It would also be possible alongside the provision of biomass for the energy sector, until other energy sources could replace biomass from both the forest and the farm – if that is what we decide we want to do. It is likely that some percentage of energy will still be sourced from biomass all the way to 2050.

Do we have the spare land to produce the wood fibre we need? While the global population continues to rise, as does the population of the UK, pressure on our finite land resources from competing demands is intense and where there is a high ratio of people to land, as in the UK, we need to be sure we are optimizing how we use our land in general. Wood fibre is only part of the picture. In this chapter, we will ask if there is sufficient land and whether it can produce enough wood fibre to meet the growing demand. In Chapter 10, we shall explore whether this can be done without negatively impacting food production.

Across the world there is a surprising amount of land that has been abandoned because human activity has ended. This includes areas which were used for farming, mining, manufacturing, settlements and so on: “since the 1950s, abandoned land has accumulated to up to 400 million ha [hectares] globally, an area roughly half the size of Australia”. At a European level, the majority of abandoned land is to be found in central and eastern Europe, including European Russia, and this is where the increase in wood fibre production could best come from. After the Second World War, these countries, all under communist regimes, nationalized their agricultural land, creating state or collective farms (only in Poland did a small number of private farms persist).

Fire can kill. A badly designed and poorly constructed building, irrespective of the materials used, can be a death trap for those who live or work there. The 2017 Grenfell Tower disaster in London stands as a stark reminder of fire's ability to destroy lives and property. Seventy-two people died, primarily from toxic smoke inhalation, in the capital city of one of the world's richest countries with one of the best emergency services.

Tall buildings, including those built from timber, can be safe buildings with a low fire risk. The issue is not one of material, but of expertise. According to Jose Torero, a world-leading authority on the fire safety of large timber buildings, “Timber can be perfectly safe if it's done right. This is not a technological or technical problem. It is fundamentally a problem of competency. The problem is whether [building designers] are competent enough to be able to make a proper assessment, and that is a much, much more complicated question”.

In this chapter the three main types of structural timber build are discussed in the context of fire: post and beam, timber-framed, and engineered timber. The material that has been used to construct the frame of the building and the material that is preventing the building from falling down is timber and hence we use the term “structural timber”.

Before discussing these different types of timber build in the context of fire, a word about saving lives and saving property. The first is infinitely more important than the second. Burnt out buildings can be rebuilt; burnt out bodies cannot. Hence when discussing fire in buildings the priority is the safety of the occupants and, if a fire does occur, the lives of the attending firefighters.

Cars are expensive to buy and it would be pretty shocking to discover they were assembled outside in all weathers. Homes are a great deal more expensive than cars and yet we do assemble them outside in all weathers – at least until the roofs go on and the windows are installed. The consensus seems to be that houses, offices, schools and all our other buildings are built the way they are because it is simply what we have always done. However, how we build is set to change and wood is at the heart of this possible change. This chapter will look at the potential to build homes like we do cars, in factories, and deliver them direct to site essentially ready, or almost ready, to inhabit. As wood is ideally suited for these factory builds – and is therefore the main construction material used – and our aim is to use more timber in the built environment for all the excellent reasons we’ve outlined, changing the way we build to one that can facilitate that is something we need to actively support.

Fans of the Channel 4 “Grand Designs” television programme may remember the 2004 episode which followed retired couple Greta and David Iredale all the way from Walton-on-Thames in England to Hartenfels in western Germany to see the “HUF HAUS” they had ordered from a catalogue being manufactured in a factory. The HUF HAUS company, active since 1921, are the “gold standard” of flat-packed, delivered-to-site, ready-to-assemble homes. Seen by many as the epitome of luxury and exclusivity, they are iconic structures of timber and glass that do not come cheap (see Figure 11.1). This exclusivity is maintained by a production limit of 200 houses per year, 40 per cent of which currently head to the UK.

At the other end of the price spectrum are Bristol-based Agile Homes who specialize in small one-, two- or three- bedroomed timber-framed houses, still with style. They are aimed at filling a specific need, usually in an urban setting, with a new home for homeless people or those on low incomes.