The developer’s view
Mario Ledermann is an internationally experienced technical leader at Lendlease, a global organisation that advocates the increased use of timber in construction.
Here is his thinking as to why now is the time for timber.
Why are you so passionate about the use of timber?
I think it really help us in dealing with a number of challenges we have as a society. Clearly the net zero agenda is something that is affecting us all. It is not just certain companies in certain industries it is everyone, all the way to individuals. I believe timber can really help us in driving a better world, in the context of reducing emissions and climate change, but also it has a number of benefits that could help us in dealing with some of the main challenges the construction industry faces, such as productivity. Being one of them least productive industries in 20 years, we haven’t improved productivity much and we need to grow the number of buildings we build since the population is growing. Timber enables offsite manufacturing, advanced manufacturing automation, which in turn will help us in becoming more productive. In the same context, dealing with quality and safety is something that timber would enable as well. So, for me, it is a combination of a number of things; climate change, but also dealing with some of the main challenges the construction industry faces.
What is Lendlease’s experience with the use of timber?
Lendlease is an international real estate and property group. We combine the disciplines of investment, development and construction and we operate in four different regions and 17 different gateway cities. Our experience with engineered timber started in 2010 when we looked at developing what, at the time, was the tallest residential building built out of engineered timber in the world – Forté apartments in Melbourne, Australia. Since then, we have built more than 20 buildings around the world using engineered timber: buildings like this one, the IQL Pavilion in the middle of London.
Why is Lendlease such as a positive advocate for the use of timber?
Sustainability is at the heart of Lendlease’s purpose and has been since day one. The creation of social environmental value is very important to us. More recently, in 2020, alongside our commitments to be a 1.5 degree aligned company, we set very ambitious targets from the perspective of the reduction of embodied carbon and carbon emissions in general. We are set to be net zero by 2025 on the scope one and two. That means the fuel we burn and the power we use will be at absolute zero by 2040. That is scope one, two and three, with no offsets. We believe these targets, alongside the nature of our global business put us in a leading position to decarbonise the construction sector. However, we know we cannot do this alone and we don’t have all the answers yet. We need to collaborate. We need to collaborate in decarbonising carbon intensive materials like concrete and steel, but we also need to work in enabling and accelerating the use of timber.
What is the typical usage of structural timber in one of your schemes?
We aim to use materials where they add the most value. In the context of the use of timber, since we work in multi-storey construction, the type of wood products we use is mainly engineered timber. Materials like cross laminated timber or glulam and a mix or a combination of them is mainly what we’ve been using around the world. As an example, the tallest building we have built to date is a building in Brisbane, 25 King Street, which is a commercial building where the use of timber was mainly in the form of cross laminated timber floors and glulam columns and beams. We also use different combinations in other parts of the world, like in the US, we have built a number of hospitality buildings where the main use of the timber being cross laminated timber in floors and walls.
Is the use of timber client driven?
Our clients and investors are increasingly interested in how we are dealing with whole life carbon and embodied carbon, so we need to consider the use of materials when developing the building. So, for example, we’ve introduced the use of low carbon steel, as well as materials with an increased recyclable content like aluminium, but we are also enabling the use of low carbon technologies that exist today like timber; that is what we do in terms of materials. Buildings like this one have a reduced amount of embodied carbon of more than 40% and that is something that clearly attracts investors and clients.
Where do you see timber fitting in with the government’s Build Back Better and Build Back Greener priorities?
When you look at the Build Back Better priorities and the talk of levelling up the whole of the UK, it supports the net zero transition, but also supports the vision of a Global Britain. Timber in construction provides us with an opportunity to substitute carbon intensive materials like concrete and steel for a lower carbon solution – today. It also enables innovation in construction and property to the use of kit of parts, or product-based approach, to design and construction into advanced manufacturing and automation.
How do you see the future for structural timber in the UK?
I believe the future is bright for timber. I think the reduction of emissions globally will still be the main driver for timber being enabled into construction. In time all the other benefits associated with productivity, quality and safety will become visible as well. So, I think there is a bright future. However, I think it is very important that we have an industry that collaborates and deals with these challenges around unfamiliarity with the technology, but also the development of the right guidance to ensure that the needs of, not just society, but key value-chain stakeholders, like developers, insurers and investors, are met.
The independent risk consultant’s view
Oliver Schofield is a Director at Lignum Risk Partners, a consultancy that provides business and risk management consultancy services to the broad UK construction market with a specific focus in the sustainable building sector.
Here is his thinking as to why now is the time for timber.
What is your background?
I have been in the alternative risk transfer and alternative financing industry since the mid-1980s. I specialise in putting together new capital solutions for hard to insure, or uninsurable risk exposures. I’m also interested in the whole timber space because we all have a responsibility, as businesses and individuals, to continue to reduce our carbon footprint and to drive towards net zero wherever we can.
What is the issue with the use of timber in construction on the UK?
The problem that we have in the UK is that there is insufficient knowledge when it comes to be able to price and underwrite the risk of timber in construction in the most appropriate manner.
Does the lack of data on timber performance restrict underwriting on timber construction projects?
No, it doesn’t. From the point of data and information there is a wealth of data all over the world where organisations have successfully used timber in construction for many, many decades. That data exists within architectural firms, within engineering firms, within overseas insurance and reinsurance firms; it exists in risk consultancy firms and in construction consultancy firms, so the data is there. The problem is that the data doesn’t relate to activity in the UK and trying to ensure that that data is transferred into a UK market environment, where underwriting can fully understand it and be able to therefore analyse it and price risk accordingly, has proved to be a major stumbling block.
Why is there a disparity in how the UK insures timber as opposed to other nations?
Part of it is due to the geographic differences that we see around the world. The risk exposures of timber building in warmer countries is going to be very different from the risk of exposure for timber building in different climates. Obviously in this country we have much more rain than in other locations and that can therefore cause problems with ingress of water. If you look at places like Australia, which typically doesn’t have as much rain as we would in the northern hemisphere, that risk is less pronounced. However, I think the other issue is that the typical model of underwriting is that data, when it is analysed, underwriters will try and analyse that from a position of, if that were to be in this country and therefore that data that we are gathering from other countries is less relevant to the activities that clients wish to undertake in the UK.
What needs to be done to increase the knowledge of timber performance?
There has been some detailed research undertaken by the large professional reinsurance market and they now have quite a useful databank of knowledge and information that they would like to be able to use to be able to provide solutions to the issue of using timber in construction in the UK. I think the second part of that is that we need to get the industry to come together to be able to share knowledge, share information, share data, share experiences so that from a pure UK perspective we can then really build that shared databank that everybody can access for the benefit of all and for the benefit of being able to push the use of timber in construction to a much higher level in this country.
Who will drive the need for the industry to come together?
I think the drive for getting the industry to work together lies at the endpoint and the endpoint is the increased use of timber in construction and therefore being able to achieve carbon net zero goals at different organisations have laid down for themselves. As we are all swimming in the same direction towards the ultimate goal, that should drive a desire for collaboration across the various strands of the overall industry. We should see the collaboration from the insurance markets, the financial markets, the reinsurance markets, which would also see collaboration from the developers, from the contractors, from the architects, the engineers, everybody involved in that space and certainly what we’ve been trying to do at Lignum Risk Partners for the last year or so is to start that conversation; to start that coming together, where people can share ideas in a very open way, but obviously having a certain amount of respect for confidentiality of their own businesses. Finding a common problem such as the unavailability of insurance for the use of timber in construction, we believe is going to help garner that effort, garner those organisations to come together to try and find a solution and therefore be willing to share their knowledge for the common good.
Can you give an overview of the Alternative Risk Transfer market?
Historically, the alternative financing market has been very supportive of industries that are facing problems when it comes to be able to find capacity at economically attractive prices and from a coverage perspective, broad enough cover for the exposures that they face. Examples that I’ve personally been involved in over many years have been putting together solutions for organisations that suddenly found themselves with very large asbestos exposures on their balance sheets. Now the traditional insurance market had drawn a line under renewing insurance policies with asbestos coverage, understandably so, but that doesn’t mean that that organisation suddenly no longer had that exposure. They needed to find a solution for that. There have also been some very noticeable examples where industry groups have come together to form a new capital solution. We’ve seen that in the North American railroads sector, we’ve seen that in the European pharmaceutical sector, we’ve seen it in the worldwide energy sector, so there are many examples where this has been successful and what we’re looking at is how can we build a new capital solution for the construction sector, specifically where they are using timber in their construction?
What is the difference between Alternative Risk Transfer and the traditional insurance market?
Typically, the alternative risk transfer and the alternative financing market are looking to support organisations, or industry groups, where there is an issue from the point of view of being able to provide capital, provide capacity, in the traditional methodology. We all know that there are many exposures that businesses face that cannot be classified as pure insurance risks and that is because the insurance market doesn’t see them as being risks that they can quantify, risks they can identify, risks they can then analyse and build a solution to. When we move into the professional reinsurance market and the financial markets, they are very keen to develop relationships with organisations who have identified and quantified those risks and are looking at a way of being able to finance those risks over a period of time. Now looking at what we were working on in the timber space, we are going to be partnering with private equity firms, capital markets, reinsurance markets, who can look at the industry and the good performance in the industry and see that actually what they are doing is for the benefit of the construction industry as a whole, but also the benefit for the climate as well and therefore they are prepared and interested to be able to use their capital to support that initiative, because they can have that relationship with the individual buyers to really get into the guts of what that organisation is doing and therefore have a much better view from what the potential for loss and potential for risk is.
What is the key to making this work for the timber market?
The exposures that businesses and industries face around the world are very challenging. The key to be able to find that new capital solution is being able to, first, fully understand what the drivers are for what that industry is looking to achieve in the short, medium and long term. Secondly, being able to understand what the risk exposures associated with those drivers are. Thirdly, being able to engage with the alternative financial market to encourage them to be able to use their capital to deploy for the creation of a new solution. These things take time. If they were readily available on the shelf, they wouldn’t be alternative, so we need time, we need consensus, we need that community of interest from various sources coming together to build that solution.
How far has your approach progressed?
We have been engaged by a group of large developers in UK to put together a feasibility study that will assess and analyse, first, the exposure those organisations face. Secondly, how they are going to drive towards carbon net zero by the increased use of timber in construction in the UK and thirdly to see whether there is a solution that can be delivered to them by accessing the alternative risk financing markets. We started that project and we are midway through it. We are engaging with those individual developers to understand fully what their demands, their needs, their blockers, their challenges are, so that we can build a solution that is appropriate for them around that.
How confident are you that we will see the increased use of mass timber in the UK?
If we start at the end of the process, which is finding a solution to enable those organisations to be able to increase the use of timber in their construction, then I’m very optimistic. We have had conversations over the last year or so with various capital providers who have all given us a very positive response to what we are trying to do, so I remain very optimistic about it. Putting aside all those outside influences such as the availability of capital, which we absolutely do believe is there. Ultimately, we all must work together to be able to find that solution to enable organisations to increase the use of timber. It is not a question of can we do this? It is the fact that we must do this.
Philip Callow is the founder of Mass Timber Risk Consulting Ltd (MTRC), a company to looking to accelerate the use of mass timber in the built environment.
Here is his thinking as to why now is the time for timber.
You founded your company MTRC ‘as a direct response to the frustrations our clients were experiencing around the insurability and lack of knowledge regards to the use of mass timber in our built environment.’ Can you outline the frustrations as a construction insurance broker and underwriter?
The main one is, as a as a broker, you turn to insurers to find the answers. Those answers can be what do you need to know, what you want to know, what should you know and what what availability of cover is out there? I think that one of the problems that I saw was that no one had an answer to that and, for the most part, if there was an answer, it was always going to be negative. So, because of those two years of being an underwriter, specifically looking about the insurability of mass timber buildings, I realised that there was a better way. That way was just stripping everything back down to the bare minimum and saying OK – who has a role to play? What is that role? What information can they bring to the table and putting that together in a way that leads to an equitable outcome for all parties.
Who are you trying to work with to achieve this?
Predominantly my work is with the developers and to a lesser extent with the insurers and brokers. Insurance brokers and underwriters need to know the details of the project, so that they can price it so that the broker can argue on the insurance on their client’s behalf, for the best possible deal, but ultimately to come to a fair, equitable landing on what that policy should be. You can’t do that unless you have the information. What we have noticed, certainly as an underwriter researching this, was that the information you need to price that risk is not forthcoming if you go about things in a traditional way. The normal way that you would build a concrete and steel building doesn’t work for mass timber. The assurances, the certainties, or perhaps the questions that need answering for an underwriter to price the risk correctly and to give a level of cover that is relevant to that project – that information needs to happen much sooner. There is a theme that will be coming out about early engagement and I say it is about early engagement and the quality of that engagement. That part is information and part of it is how you present it. Put simply, that refers to breaking down of how we do things. It is how we used to do things when I first started my career. We had a hard market and it would take many months, including international travel in some instances, to speak to underwriters around the globe and get them on board with a major infrastructure project. Like, for example, Crossrail. They are big, the values are huge, the engineering is a challenge, but there’s no difference for mass timber building, the engineering is a challenge. The safety of that project is a challenge which is why you need to break it back down, get the information presented at the right time to the underwriters to get an equitable outcome.
Which stakeholder community, in your opinion, is the biggest barrier to the adoption of mass timber and how do you manage this?
Without a shadow of doubt, it is the government – we are trying to manage that. There is some excellent lobbying work I started with The Alliance for Sustainable Building Products (ASBP) and is now continuing with Built by Nature. I know that an excellent group of stakeholders across insurance, across architecture, across engineerin, fire risk engineering is working towards lobbying the government to press for support. I think it would be unfair to say that the government is not willing, I think they are willing. We saw that from the outcome of COP26 and we’ve seen that from the strategy going forward. But I think they could do a lot more. I think that that is the biggest barrier.
How do the insurance brokers that you work with view the use of mass timber?
I think they all want it to come, like most responsible members of society. I think the better ones look at it as a challenge, just like I mentioned how Crossrail would have been a major challenge from an insurance broking perspective. Any broker that enjoys what they do loves the challenge of taking something, which on the face of it looks difficult – close to impossible – and using the information available and helping the clients and the stakeholders in that project delivery team present that information in the right way. It is something you must create. That information that they haven’t been asked before and they need to provide it. I think they really do view that as a great challenge. However, I think they are rightly, incredibly frustrated. The response to UK insurers is as negative as it is. We work in a global insurance market here in London and, unfortunately and fortunately, what happens around the world is felt in London and therefore the UK insurance market. I know brokers that are being approached by clients who are multinational who are finding no problems, or limited problems, in securing extra insurance in North America, or Europe with ‘insurer X’, but when the broker approaches ‘insurer X’ in London for a UK project it’s an immediate ‘No’. I think everyone can see a frustration with that, but if you’re in the market, if you are practising broker, it is incredibly frustrating because there is no message to your client that will help saying that ‘insurer X’ won’t do it, but your client is saying ‘well that’s rubbish they’re doing it for me in North America’. That is madness and I think there is something that the insurance community, particularly the carriers really need to look at, because it is unfair that the elements, the physics, the chemistry around the topic of mass timber is the same in North America and Europe, as it is in the UK. That is something that I think is up there with government strategy around this is the second largest barrier to this.
What do insurers need to know to help them feel secure in insuring structural timber construction projects?
Data is key here and it almost sounds obvious, but insurance is based on knowing how something performs. With mass timber we simply don’t have the volume, whether it be in North America or Europe, or anywhere else, that gives insurers the comfort to not have to delve much deeper into the risk dynamics and the parameters of a particular project. That makes it very hard, because fundamentally that lack of data means a lack of projects which means it’s not paying your bills, it’s not meeting your targets, it’s not going to change your business in any given year. So, then you must put a lot more effort into looking at that risk and underwriting that risk, when you’re struggling to make a profit doing the traditional type builds and across both property and construction. So, it is a very challenging landscape for an insurer just doing the day job. So, inputting something that has no data that is obviously a volatile material, in so far as we know timber burns, producing a great strain on underwriters to be able to look at that. In their defence, they do need that data and it isn’t there. Testing is one area that people like to look at. There is a lot of work going on around that, the Structural Timber Association are going to be the conduit for the results and open source format, but one can test for a particular outcome and I think that that is where there is a little bit of a chicken and egg – we need more of these things being built, we need to prove that certain typology, or methodology, or system when employed, is safe. But that takes time. Perhaps we don’t have that time now, not if we’re going to meet our net zero aims.
What should the construction industry be doing in relation to these insurers?
Everywhere you go, when you start talking to the people who design and build these projects, you can tell there is brilliance and excellence. No one sets off in the morning to go. “I’m going to mess up today, I’m not going to do my job to the best of its ability.” When you start scratching beneath the surface, the wealth of knowledge and expertise from people who are prepared to learn, who want to learn, which I would like to think is the vast majority, the engineering and architectural community; what they’re learning and what they know is fantastic. What they are not doing is sharing that knowledge. Not from a “I don’t want to share” perspective, but with insurers and with their brokers. Every time I’ve asked the question as to how do you do this, they’ve got the answer and every time I’ve said, “why aren’t you telling?” – “Well, no one’s asked!” I accept that it is up to an insurer or broker to ask, but perhaps that’s where you need to guide them, you know more than anyone. Your experience on how to rectify issues, your experience on how to control moisture, your experience on how to rectify damage, this is all golden information that needs to be shared with insurers. Every time we have asked, when it’s gone wrong, give us examples of how it has been fixed, the walls come up. I totally get confidentiality, but we have got to be all in this together. Every constituent part needs to play their bit to move this forward. I think the construction industry needs to get better at telling us how good they are. We are very quick to judge and say how bad they are, but there are all sorts of things that they are doing that can demonstrate their quality. I think that it is important, but patience is required, which has not been something that they have needed in the past when it comes to purchasing insurance. That goes back to the idea of early engagement. Just selling their story and being prepared to be open and being able to say, “we don’t know that and the fact that we know we don’t know means we’re going to find out.” That’s super reassuring from an underwriter’s perspective because that gives you comfort that you are working with people who are going to solve a problem and solve in a logical and right way.
You make it sound so easy…
It is very easy. I think that is why this is really got under my skin and several other people’s skins, is because it is easy, but we’ve all got to do something a little bit different and that is the difficult part. It is like getting up early to go to the gym, when you know you are overweight – you know what to do, you are just maybe not going to go and do it! Until you get used to going and doing it, which is hard at the beginning, then it becomes second nature and then it becomes easier. Then you can maintain that food throughout the life of whatever you’re doing. That is why I think several of us, in this area, are so frustrated because we can see that just little tweaks to how you go about doing things and everyone will go on that same journey with you. There will be hiccups, there will be losses, we know that. The insurance market has no problem with paying losses, but they have massive problems with paying losses when you have not done your due diligence, when an underwriter has not done what he could have been reasonably expected to have done to be prudent. That is where things need to happen differently and that is where developers, architects, engineers need to really start opening up and say that we will take you on that journey, because we will learn as well.
Does the UK’s attitude to mass timber differ from that of the rest of the world? If so, how and why?
Yes, I think it does. I think that Grenfell really changed the UK’s perception. It is such a shame because what was fraudulent workmanship that led to what should have been a robust engineered solution, if it had been erected correctly, to prevent fire spread. I think that sadly and ironically, given it was man-made materials that led to the fire spreading, it massively pushed back and for the right reasons, that we must ensure these buildings are safe. Any building is safe, but surely if we can ensure quality of workmanship, we can avoid these issues. If we can ensure testing and performance is adequately measured and that when it comes to mass timber, we can look to other other geographies for that. It is a real shame that we are in this situation, particularly given our need to reduce our CO2 emissions, I think that is the biggest issue we have here. We need to look at the supply chain as well. We don’t have a robust timber supply chain in the UK to match our mass timber ambitions. We look to Europe and Scandinavia for that. They have plenty and we have supply chain issues in general now, but I am sure that we all know they will pass. That doesn’t necessarily help, give that we haven’t got that home grown nature. I should caveat that in the US, they have an unbelievably well-funded timber lobby group, that they are used to building out of, what we would call, frame in the insurance world, which is really four-by-two stick built. They are also used to them burning down, a lot, certainly during construction, which doesn’t help, by the way, that there are significant losses every six to 12 months in the US market, but they have volume and data. There is enough premium. The market knows that these things happen, so again, we have the Grenfell issue, which is entirely right to due process and understanding that would prevent it from happening. We have a supply issue. Whereas, conversely, go to Scotland and Wales there’s a lot of timber being used, a lot more than I think a lot of people realise. Then we have the wider money that somewhere like the US or Scandinavia will use, whether it be government incentives, or whether it be just the commercial sector.
In your time in the industry has the market improved in the adoption of mass timber?
Yes, in the UK absolutely. When I started the underwriting journey, a couple of years ago, on mass timber research we found that from a risk perspective there were some excellent work already done. The prime one is the 16-steps to fire safety and that’s a direct result of events and learnings. It is a great example of how we learn from our mistakes. That’s meant that, from a construction perspective, it was a long journey for us to launch the UK’s first mass timber construction insurance facility. Sadly, that no longer exists because there was no volume, we had no-one asking us for quotes, apart from a handful, so how much interest is out there? One of the issues was that long standing relationships and markets relationships are unequal. Brokers would go and do certain things, but they would get insurance on construction. I would say to anyone now, you can get a construction insurance policy. Not ‘no problem’, you need to do things in a slightly different way and you need to be more open with information, but it is absolutely available and I think two to three years ago it really wasn’t. The remaining issue is with property insurance and I think we have not seen a big change. That, I think, is the most frustrating because we need to temper that frustration and a lot of developers and owners will say well ‘OK, but I can get an excellent construction policy now but in three to four year’s time what will my property insurance policy be now?’ Quite frankly they will not get an answer and any answer will be negative. Now, we need to take a step back there, if you’re a developer and say, well I can’t get a price for my car insurance or my household insurance for three years and about why are you any different? No underwriter will give you that price because they’re not allowed to because the market changes for good and for bad in those intervening years and therefore the price will change. So, no-one is going to commit to that, so we must start looking at what is the commercial driver? We all have a part to play here and maybe the developers, the owners, have a part to play…what’s your worst case scenario? Can we afford that? Can a potential buyer of this property afford that? If the answer is yes, well let’s crack on because then it comes back to data and then it comes back to experience and then it comes back to, we’ve answered those questions, we’ve got more of these buildings and the price will come down. That is inevitable. We are further forward, but I think certainly, from an insurance on the property space, we need to do a lot more work. We need insurers to be a lot braver with qualified data – they can do that and we need developers and owners to be braver; to perhaps not expect insurers to just take their balance sheet issues, to look at more inventive, more effective and inventive ways of managing those balance sheet issues, so that they’re not just all risk transferred to insurers who will not take on what you yourself would not take on. Strip those away and then you will find there is an extra relationship that you can build… but I don’t think we are there yet. I have a feeling that the tea leaves are indicating that we’re at the cusp of that and I think more than ever the conversation is now being had. We have some thought leadership events coming up being hosted in the Lloyds building which is great! Not just a room. They are providing more than that, they’re now really looking at this to be something that they need to get more involved in, as a thought leader. It doesn’t mean that they will push insurers to do something. That is not how they operate. That is not how the market operates, but it is the analogy of leading a horse to water. They are just building the trough and that is what we all need to do. Much more of that is happening now.
How confident are you that we will see the increased use of mass timber in the UK?
I am confident. I think the insurance market will always adapt and change. If you are of the belief that itis the insurance market that is the problem, then be confident that will change. My view is that it is government and the developers, the owners that need to take more responsibility. We’ve mentioned that the government’s policy is maybe not fast, but it is certainly changing towards the use of mass timber and we have mentioned Grenfell and the effect of that. With CO2 emissions, net zero, COP26 having been in this country, I think we’re going in the right direction. Finally, the developers – they are seeing that they have got more of a role to play here. Not just in saying, “you’ve got four weeks to get me an insurance policy please”. That doesn’t work anymore and taking people on that journey. They are now understanding that. They are also putting their money where their mouth is with regards to exploring alternative risk transfer mechanisms. That is really encouraging because the people who wanted to buy the insurance policies are exploring ways of being brave enough to help with that insurance themselves, which really exposes their balance sheets. There are some great little bodies of work going on, there is some wonderful coordination being done by a handful of organisations with regards to thought leadership in this space and obviously the Built by Nature accelerator fund which is relatively new and is doing great work in advancing the use of timber in the built environment. I am hopeful just like with all those little factors and little aspects, all doing their part that everyone else is starting to understand that they have a part to play in this as well, whether it be developers, structural engineers, fire risk engineers, architects, contractors, specialist and non-specialist contractors and then ultimately the insurers and the insurance brokers and advancing all of our knowledge. I am very confident that we will see widespread adoption of this, certainly in the next decade. I will put my hand up and say I think by 2030 that we will have very few of the problems that we have today. We have all learnt about CO2 and the effects on the environment, whether you are a believer in that or not, let’s just think about using sustainable products in our built environment. It makes more sense to use a tree that we can grow than to use resources out of the ground that we can’t replace. That seems good business sense to me. Even if you’re the most ardent climate change sceptic, it is good business to use something and sell it for a profit that you can grow back. That will happen. If we come back to data being a major issue, by 2030 will have more data, simple. By that stage, with ESG, when it comes to the corporate sense, from both insurers and investors and a need to be much more engaged and to do actionable, auditable things around ESG and EU taxonomy, which we are fully a part of within the UK, there is a lot coming, which means that everyone should be jumping on this bandwagon and everyone should be doing their part to learn, to understand what we’re talking about here; to understand the risk, understand how to mitigate it and be able to provide an equitable solution… but everyone has a part to play and that’s that goes back full circle to why I am doing this.
“He’s a builder, he’ll just know how to build it.” This was the response Tabitha Binding, Head of Education and Engagement at Timber Development UK, received when supporting a winning group of student architects to make their successful timber-framed concept an installation reality at the London Design Festival.
Yet when Tabitha sat down with the architects and expert carpenter enlisted to build the installation, they found they were all talking a completely different language.
The architects were communicating with 3D software, while the carpenter, using pencil and paper, was seeking to understand how the dimensions met to ensure the structure would be supported correctly. Through collaboration, help from other timber trade experts and hands-on experience during the installation’s construction, all parties shared their knowledge and the communication barriers disappeared.
Encouraging education and engagement around the use of timber in construction, as Tabitha’s job title suggests, is exactly what her role is all about. During this interview, we discover why we need to educate and upskill the students of today, who will become tomorrow’s specifiers, designers, engineers, project managers, quantity surveyors and contractors. We need everyone to understand how to use timber wisely if we are going to create a future full of low-carbon timber construction.
What is your role and why is it important for timber construction?
I work with industry, professionals, academia, and students to enthuse, encourage and educate – to increase knowledge and competency in timber as we transition to a biobased economy.
With 5,000 architecture and 5,000 engineering students entering the world of construction and the built environment every year, business as usual is no longer an option. We have to change the way we build to create a low carbon, sustainable future.
We spend our lifetime in buildings and most of our money on our homes. And yet, while architecture and engineering are viewed as ‘suitable’ career choices, construction itself often isn’t, despite its vital importance to the UK economy. Let’s face it, without construction experts to build our homes and buildings, we’d be pretty stuck.
The most impactful decisions on carbon emissions in the built environment are made long before the foundations of a building are laid down. They happen in architects’ studios, within the offices of city planners, and in the engineering space. Decisions made during the project development phases impact both operational and embodied emissions, as well as how residents will live and work in these structures.
My role is to bring the design and delivery disciplines together to build better and understand more clearly the purpose of each building, to give everyone pride in their work and stimulate mutual respect across the timber construction supply chain.
What are the main roadblocks to creating low-carbon buildings in the UK?
One of the key roadblocks has been the educational gap around timber, which often features as little more than a day of learning and coursework within some universities. Departments can be disparate with scant collaboration across the built environment subjects, and some less progressive universities are even still teaching outdated methodologies. As a result, many students simply don’t know any better. Many also don’t have any hands-on experience that can contribute to a more rounded and knowledgeable approach to timber construction.
This means graduates emerge without the knowledge, ability, or confidence to employ timber systems. With our University Engagement Programme, we are seeking to change this – and make timber systems and technologies a core pillar of any built environment course in the UK.
What other initiatives are you implementing to overcome the timber-related education gap?
An important part of what I do is delivering project-based learning that breaks down barriers between professions, and facilitates dynamic learning and practical, transferable timber skills.
One way we do this is by running interdisciplinary challenges where Timber Development UK (TDUK), the now amalgamated Timber Trade Federation (TTF) and Timber Research and Development Association (TRADA), hosts a workshop based on a real-life project.
For example, the one we did just before lockdown was sponsored by timber industry partners and saw 58 students from universities across the UK gather at Cardiff University and compete to design, cost and engineer the best low-carbon, energy and water efficient timber community housing in less than 48 hours.
Each team consisted of student engineers, architects, architectural technologists, quantity surveyors and landscape architects, and received hands-on support from pioneering design professionals and industry members, including judges from Mikhail Riches, Cullinan Studio, Stride Treglown, Ramboll, BuroHappold, Entuitive, Gardiner & Theobald and PLAN:design.
How is the STA supporting your quest?
Last year’s competition Riverside Sunderland University Design Challenge (RSUDC21), saw 300 students design, engineer, plan and cost a three-bed family home along with an indicative masterplan for 100 homes to meet RIBA2030 Climate Challenge targets – with low-carbon timber and timber-hybrid systems providing the main material focus.
The STA’s chief executive, Andrew Carpenter, spoke directly to the students during the weekly Friday ‘virtual catch up’ session and enabled access to the STA’s vast information library whilst the Association’s Technical Consultant also supported the event, delivering a webinar on timber and fire. They were among 78 professionals who participated across a 12-part webinar series, which proved to be a unique and ambitious learning opportunity for the whole industry. Experts presented on everything from sustainable timber and offsite manufacturing, counting carbon, timber challenges and structural engineering to how you cost and budget timber to post-occupancy evaluation – the webinar series is still available as a learning asset on YouTube.
Are there any specific hotspots in the timber supply chain that you’re focusing on going forward?
Yes, definitely. One hotspot is the point at which design and construction meet. Tackling this collision proactively, I’m currently working strategically with New Model Institute for Technology and Engineering (NMITE) as its Centre for Advanced Timber Technology (CATT) Lead for External Engagements and Partnerships to deliver training that encourages greater design and construction collaboration across the supply chain.
We’re looking to develop some short courses and CPDs into a longer Bachelors degree in Sustainable Built Environment over the next year and, starting in September 2022, we will be running some interactive education days that will bring together the whole supply chain.
These will invite architects, engineers, clients and cost consultants, contractors and timber industry supply chain experts, such as offsite frame manufacturers, to up skill, reskill and address topical industry issues. Topics on the table embrace everything from level foundations to air tightness and energy performance and, of course, tackling the reduction in carbon at element, building and operational levels. Allowing people to exchange really good knowledge and encourage more collaboration will ensure that where we build with timber, we also build better with timber.
How did you find yourself in the timber industry?
I started out aged 17 working with coppiced hazel and softwood thinning. My first engagement with the timber construction industry was when I joined the Welsh timber charity Coed Cymru Cyf in 2010. The charity focuses on creating and managing Welsh woodlands for multiple benefits.
From there I was involved with ‘Tŷ Unnos’ – literally translated as ‘a house in one night’. The name was chosen to convey a fast and adaptable building system making use of local material and local labour, all based around Welsh timber. It led to the development of a fully certified volumetric offsite system, where buildings left the factory fully finished and fitted. That’s when I got involved with post occupancy evaluation, design for manufacture and assembly, plus disassembly & reuse and the Passivhaus energy efficiency standard.
I’ve also worked on European technical guidance, thermal modification of Larch for joinery with Bangor University, a Wood Encouragement Policy with Wood Knowledge Wales, which was adopted by Powys County Council in 2017 and, more recently, joined TRADA in 2018 to focus on education and engagement in universities. The rest, as they say, is history!
Do you have a takeaway message for the industry?
Absolutely. It’s all about collaboration early on. If we work together across disciplines we will have more fun, be more productive, less wasteful and create better buildings that are both energy and resource efficient and beneficial to human and planetary health.
To join in, keep an eye on the new Timber Development UK website for the collaborative opportunities arising when we launch in September. https://timberdevelopment.uk
Connect with Tabitha Binding on LinkedIn
The STA echoes this collaborative approach, working closely with members, stakeholders and the UK construction industry to address the issues that timber construction faces. The STA’s mission is to enhance quality and drive product innovation through technical guidance and research, underpinned by a members’ quality standard assessment – the STA Assure Membership and Quality Standards Scheme.
For more information visit: https://ttf.co.uk/
Stewart Dalgarno is the Director of Innovation and Sustainability at the Stewart Milne Group, one of the UK’s largest independent award-winning housebuilders. Here is his thinking as to why now is the time for timber.
How do you develop your expertise in timber construction?
I developed my expertise in timber construction through working with the Stewart Milne Group for the last 38 years, as a house builder and as a timber frame manufacture. During that whole career I have lived and breathed timber frame construction, at the core of what we do, as a residential house builder.
What are you such an advocate for the use of timber in construction?
I am an advocate for the use of timber in construction because I just think it is the right thing to do from a sustainability point, but commercially, from a profit point of view, it is the most valuable commercial, attractive, simplest way to build homes. For the last 30 years we’ve been using timber construction and we would not be in the place we are today without using timber.
How has the industry changed in the time that you have been involved?
I have seen lots of changes in the industry since I’ve been involved, with the growth in the marketplace for timber frame construction in Scotland – 85% is timber framed. This is my heritage. I’m glad to see in England it has also increased now and will continue to grow. We’ve seen challenges come our way, but we have improved solutions that give us confidence going forward, to see the challenges in net zero carbon. On many occasions we’ve developed net zero carbon homes that will be, I think, something we will be proud of going forward in the future of the industry.
What are the benefits of modern methods of construction (MMC)?
The benefits of MMC are clear in my mind. As a housebuilder we see speed, quality, surety – a build on time – as being critical. Also, we are less reliant on bricklaying and critical skills are short in the marketplace. Using timber frame construction, for us, solves all of that.
Why is timber frame NOT the preferred method for many housebuilders?
The barriers to the uptake of timber construction I think of are just knowledge and sharing of good and bad experiences and learning from that – overcoming some of the perceptions that will arrive in the marketplace. For 45 years we’ve been building timber frame homes. We can get insurance. We can get warranty. We can get mortgages. We have never had a problem in our history of building timber frame homes.
What more needs to be done to increase the use of timber?
There’s more we can do to educate people on timber construction. There are lots of new forms of timber related construction in the market, such CLT (cross laminated timber) mass timber construction. So, more tests…more education…more knowledge centres. More innovation brings confidence in the marketplace, taking people with us on the journey – key people like warranty providers, lenders and insurers. To me that is one of the key things we should be doing more of to encourage more timber being used in the sector.
Can you summarise the benefits of timber for us?
The benefits of using timber compared to other materials for house builders is really the speed, quality, but really the sustainability credentials. We are finding through our ESG requirements nowadays that it is quite important to demonstrate, by using low embodied carbon materials. The fact that we use timber gives us a tick in that box, substantially, straight away.
What is the wider market for the use of timber in the housebuilding sector?
The wider market for timber frame is exciting and it’s progressing quite a lot. We see a lot of new housebuilders coming into the marketplace, small SME type developers, private rental developers, affordable developers and they’re all looking to use smart ways of building homes and really timber frame here is the ‘here and now’ answer for them.
How does timber frame meet the needs of the Government’s ‘Build Back Greener’ strategy?
Timber frame construction meets the build back better, build back green agenda because of its sustainability credentials. The fact there are less skills needed on a timber frame housing site than a traditional site and it’s just viable, so we can all enjoy the economic benefits of building new homes here in the UK.
How have you found your dealings with the insurance industry and what does it need to understand?
We have worked with them for many, many years and we ensure we have got the right standards, right qualities, the right fire tests of the kits and everything you need to technically prove this is a ‘here and now’ proven solution.
How does timber fit with the Future Homes Standard?
Timber fits with the Future Homes Standard very well. One of the key criteria of that is an energy efficient fabric. We have always believed in a fabric first approach, fit and forget, where you have got the insulation within the timber frame wall system and therefore you are reducing the heat load. That allows other technologies like solar panels and heat pumps that then decarbonize your home, to make the Future Homes Standard, to get to a net zero carbon outcome.
What do you think is the future for timber frame construction?
The future for timber frame construction, for me, is to do more in the factory and less on site. We’ve got a good heritage of making things, we can do more in the factory through automation – to put in insulation, put in windows, then maybe cladding, then maybe services. We’re bring a whole house system, a panelised system. We firmly believe it is the way to go. We think timber frame can be at the heart of that future.
Andrew Waugh, Founder and Director at Waugh Thistleton Architects, was part of a recent visit by Construction Minister Lee Rowley MP’s to The Black & White Building. Designed by Waugh Thistleton and owned by The Office Group (TOG), the fully engineered timber building providing premium flexible working space, will be the tallest timber office structure in London. Andrew discusses why the visit was so crucial to the Confederation of Timber Industries (CTI), which is an umbrella organisation representing the UK’s timber supply chain, and with which Waugh Thistleton is in partnership.
Government legislation that promotes the use of timber throughout the construction industry is required in order for the UK to meet its net-zero commitments. However, due to the number of interwoven alliances and systems within the legislation, it’s simply not as easy as taking building materials out and replacing them with another, which poses a big problem. There are also more speculative parts of the industry that present challenges, such as the nervousness and concern surrounding insurance and pricing.
The minister’s visit to The Black & White Building was crucial because it was proof of concept. We were able to demonstrate that timber constructions are cost equivalent to a concrete building, faster to construct, ensure better working conditions on-site and produce a building with a higher financial value. Additionally, landfill waste is minimised and there’s an 80% reduction in site deliveries, which all contribute to more sustainable construction practices. We were able to show the minster what a low carbon construction can look like.
A lot of work around sustainability over the past 20 years has been centred on layering additional systems such as triple glazing, the addition of more insulation, building management systems and mechanical heat recovery, but what we really should be focusing on is making things simpler. Timber buildings allow us to find the beauty in simplicity, and to design sufficiently for the purpose of the building and not beyond, which is something that the latest Intergovernmental Panel on Climate Change (IPCC) report explores in more detail along with a global assessment of climate change mitigation progress, along with potential approaches to the overall issue.
It is a fact that timber is currently the only viable alternative to steel and concrete, additionally, it is an existing technology with a sophisticated supply chain. We must reduce our reliance on steel and concrete, ideally by reducing the use of both materials by 50% in the next 8 years, and replacing them with timber. As timber is a uniquely replenishable structural building material for high-density urban construction, we have the opportunity to demonstrate a clear alternative way of doing things, by using an existing system to prompt the evolution of construction.
These changes must happen immediately, and in terms of demand and availability, timber is incredibly well-suited to adopt this in a short time span. In Europe, more than half of the trees felled are burned, so we haven’t even begun to scratch the surface of the opportunities with timber, and the timber manufacturing industry is growing exponentially. Governments in Europe and North America are changing their changing building codes and adapting legislation to promote the use of structural timber; the UK is unique only in its failure to do so with the same haste.
It was incredibly important for the minister to visit The Black & White Building to get a good look at what the other countries are getting so excited about, which is a technology that was innovated in the UK and exported around the world by UK firms. The time is upon us to catch up and for the UK Government to take the same action that many others have already taken.
To learn more about The Black & White Building, and other Waugh Thistleton sustainable projects, visit: https://waughthistleton.com/practice/
To read about the Construction Minister’s visit to The Black & White Building, visit: https://www.structuraltimber.co.uk/news/structural-timber-news/uk-construction-minister-visits-ground-breaking-low-carbon-timber-building-in-london/
Using the generic term ‘wood’ is analogous to using the word ‘food’. Wood covers an estimated global diversity of over 20,000 woody species of plant. A few thousand of these are commercially used and these are as diverse as the cultures that use them. Wherever we look, the use of wood is deeply rooted in human history and indeed in everything we do today.
When I think of ‘wood’ I think of an ingredient that can be transformed from a renewable material resource into a gourmet feast of colour, texture, and pattern or used simply as a mass-produced component that we order from the builders’ merchant. The designs we dream up sometimes rely on individual trees where we want something special, but we are most likely to rely on standard sawn or Planed All Round Timber (PAR) sizes harvested and converted from forest trees and readily connectable using metal fixings like a Meccano set. Whichever way we use wood we must only specify sustainably sourced timber from schemes such as the Forest Stewardship Council (FSC) or Forest Law Enforcement, Governance and Trade (FLEGT) to help protect them as a regenerative resource. Thankfully most timber suppliers now endorse these schemes and provide a range of timber products with trusted certification.
There is no other material like wood and it is so easy to use once you have familiarized yourself with its properties and available sizes, which do vary considerably from softwood to hardwood and across the available species. As an architect, this is what makes designing, specifying, making joinery and furniture and especially working with those skilled in the art of woodwork in all its forms, so rewarding.
The versatility of the material is as diverse as its applications. The relative lightness of this material is balanced by its strength and for some species, the ratio of these is better than steel. When exposed as a finish there are exquisite tactile qualities to choose from as well as a softness in light which is so appealing in exposed CLT construction. There are now multi-occupancy buildings where CLT has been used as a wall or ceiling finish – even the stairs and furniture can be made from this material. These advantages of using the wood stem from the connections to the forest that is then recreated itself in the home.
Cutting edge zero-carbon houses need to incorporate as much wood as possible to sequester carbon. This is important as it is the most practical way to reduce or even produce a negative carbon footprint. But the mindset for sustainable thinking starts with choosing the right materials. Foundations can be minimised using light timber framing and by making the most of the engineered timber products available which now play a significant role in MMC. I also see more interest in systems that are hybrid in nature and incorporate steel connections and consider thermal mass to assist with mitigating overheating now that the new Approved Document O must be met. Meeting the overall building physics strategy is essential to futureproof the asset so that it is insurable, mortgageable and comfortable to live in.
Moving up the scale, multi-occupancy mid-rise apartments can be constructed in timber frames or CLT but architects and engineers must understand the material and its possibilities and limitations. A decade ago, when low U-values became central to developers’ sustainability ambitions and Approved Document L of the Building Regulations cranked up demands for lower U-values, the Structural Timber Association (STA) began to develop new high performance-tested wall, floor and roof types to address this. These now form pattern books available for download on their website.
Architects’ demands on timber frame-based building systems must now change to align with the requirements of the Building Safety Bill. Design teams are now expected to demonstrate that they have the relevant experience and expertise to design buildings and are expected to use comprehensively tested systems and to pass Gateway 2. No home should be built unless it is constructed safely and competently and, of course, can be maintained as such thereafter. This is foremost for the protection of life enshrined in the Approved Documents or Building Regulations but also – and of rising importance for insurers – is the robustness of fire protection for the building as an asset.
For structural timber or any other MMC system for that matter, the complete assembly of parts and systems forming a multi-occupancy building must meet the performance requirements for fire, airtightness and acoustic performance as a whole. This must be done within the context of changing guidance like the impending changes to BS EN 9991, the forthcoming updates to Approved Documents B and L of the Building Regulations, updated Future Homes Standards and other guidance which is generally becoming more prescriptive.
The insurance industry has raised concerns about the protection of timber structures from fire and water ingress and the STA has done much to put the timber frame industry at the forefront of addressing these issues. However, it is worth reflecting that the principles of fire safety also apply to other MMC construction systems like those that use cold or hot rolled steel framing or those built as volumetric units. Architects are very reliant on the technical know-how and expertise of manufacturers who design and test their own systems or on fire engineering specialists who form part of the design team. Encouragingly the STA has pooled much of the test information from timber frame manufacturers into one place on their website to add to their own.
We cannot live without healthy forests and perhaps many of us cannot live without wood in our lives, whether that be a timber-framed house or everyday furniture. We must make sure that these homes are constructed to the very highest technical standards and as buildings that must also play a big part in the fight against climate change.
Andrew Carpenter, CEO of the Structural Timber Association, explains how the use of timber in building construction can be beneficial for occupants and their well-being.
On average, we spend around 90% of our time indoors and there is a growing appreciation that the buildings we inhabit can have a significant impact on both our mental and physical health. The design and construction of the building can affect this in a number of ways from physical factors such as indoor air quality, acoustics and lighting to the psychological influences of the layout and materials used. Studies have shown that concentration levels in offices, learning and development in educational establishments, and even patient outcomes in healthcare buildings are all affected by our surroundings.
The use of timber in construction is growing due to the sustainability of the material as the only truly renewable building resource. and expanding its use throughout the building can have a number of health and well-being benefits.
Firstly, timber has been shown to reduce stress. A study by the University of British Columbia and FPInnovations found that the presence of wood surfaces in a room lowered sympathetic nervous system (SNS) activation. This is the system responsible for physiological stress responses and is also intrinsically linked to blood pressure, digestion and healing.
Timber within buildings has also been shown to improve physical and mental wellbeing in other ways. A study commissioned by Forest and Wood Products Australia surveyed 1,000 Australian workers and found a correlation between the presence of wood and higher overall satisfaction and lower absenteeism levels, as well as improved concentration and productivity among employees.
Furthermore, timber offers better acoustic performance than other hard surfaces used in building design. Its ability to absorb sound prevents echoes and noise transmission through the building, creating a quieter and more peaceful environment.
Finally, given the link between timber and sustainability, the use of timber can have a positive influence on peoples’ perception of the buildings they inhabit. For example, people can feel good about living in a home constructed of natural materials. In a study conducted by the BRE, 62% of respondents saw climate change as an issue they should be concerned about and 96% said that they had already made changes to be more sustainable. Additionally, 43% said they would prefer to buy or rent a home that had a sustainability certification. In fact, approximately 1 in 5 were prepared to pay more for such a property.
The buildings we live, work and learn in represent a significant part of our daily environment and as such have an important role in our health and well-being. In addition to its well-documented structural and environmental benefits, timber can also help to create healthier places for people.
As the Government works to ‘build back greener’, the Confederation of Timber Industries (CTI) in partnership with Waugh-Thistleton Architects have hosted the UK Construction Minister Lee Rowley, on a site visit to the Black and White building.
The Minister was taken for a tour of the exemplary fully engineered timber building, which is owned by The Office Group (TOG), the premium flexible workspace provider with a platform of more than 50 buildings across the UK and Germany and will be the tallest timber office structure in London when complete later this year.
Boasting a powerful sustainable agenda, the hybrid structure comprising beech Laminated Veneer Lumbar (LVL) frame with Cross Laminated Timber (CLT) has resulted in 37% less embodied carbon than an equivalent structure built using steel or concrete, demonstrating how a shift towards the use of biogenic materials in construction could help the industry to significantly reduce its impact on the environment.
Following its release of the Build Back Greener Strategy Document, the Government has signalled a clear intent to increase the use of sustainable materials, such as timber, within construction as it seeks to meet its Net Zero obligations.
Key to the success of this endeavour, is increasing the awareness and knowledge of structural timber. As such, the CTI is actively engaging with the Government and other stakeholders via the Timber in Construction working group, set up to develop a policy roadmap to help the Government deliver on its environmental ambitions.
Speaking on the visit is Andrew Carpenter, Director at the Confederation of Timber Industries: “Independent bodies such as the Climate Change Committee have already said that increasing the use of timber within construction is crucial to achieving net zero status by 2050, because of the low-carbon benefits of these forms of construction.
“The sustainable benefits of timber as a form of carbon capture and storage are widely known, and today has been about illustrating how these benefits are already being delivered safely across the UK, as well as globally, to create a new wave of low-carbon construction.
“In partnership with the UK Government via the Timber in Construction Working Group, and together with members of Parliament through our APPG for the Timber Industries, we are helping bring forwards the benefits of greater use of structural timber.”
Construction Minister Lee Rowley commented: “It was fantastic to visit the Black and White building to see how this innovative approach to building, harnessing engineered timber, is helping to drive sustainability in the construction sector.
“The site’s construction is an excellent example of the benefits timber buildings can bring and I look forward to seeing it when it is complete and in operation.”
Andrew Waugh, Founder and Director at Waugh Thistleton Architects, commented: “It’s great to see the Government taking an interest in engineered timber construction. We need Government leadership and systemic support for the use of regenerative, low carbon construction materials if we are to have any chance of reducing the impact of our industry on the planet.”
Charlie Green, co-Founder and co-CEO of TOG commented: “The Black and White Building is set to be Central London’s tallest mass timber office building. Alongside Waugh Thistleton, we have worked to reduce embodied carbon as much as possible, delivering a building that represents what future workspaces should be.
“It has never been more important to develop techniques and approaches that deliver buildings for a better world. Innovative construction processes and sustainable materials, like those employed here, will form a central part of the sector’s journey to net zero over the coming years.
“We’re really pleased that Lee Rowley, MP, visited the site today to see this evolution in practice and look forward to further engagement.”
For more information on the Confederation of Timber Industries, please visit: www.cti-timber.org.
For more information on the Waugh-Thistleton, please visit https://waughthistleton.com/
WHEN DOES TIMBER MAKE SENSE?
Individuals can make a limited difference to the climate challenge with their daily choices. Yes, we can all do lots of green things in our lives – we can choose not to fly, drive electric cars and eat less meat – this is of course important, but in most instances the reality is that reducing professional emissions will have the biggest impact on achieving a low-carbon society.
As a structural engineer, I am personally responsible for managing huge masses of carbon dioxide. With the strike of a pen, I could add hundreds of tonnes of CO2 into the atmosphere – or make significant savings. That is why it is so crucial that those of us who specify buildings recognise the enormous importance of choosing lower-carbon solutions where possible.
Currently, the construction industry represents around 10% of total UK carbon emissions and directly contributes to a further 47%. As a result, the industry finds itself in a position of great accountability and influence with regards to the nation’s climate change efforts.
Those who design buildings and the structural engineers who determine the frame type have a huge responsibility within the construction industry. Typically, a UK structural engineer’s professional carbon footprint is around 160 times their personal carbon footprint for scope 1 and 2 emissions.
While the industry is taking steps to develop more sustainable working practices, there is a corresponding growth in demand for more sustainable development options from employers and investors and the industry needs to respond to that demand.
Enhanced public awareness of climate change, including a growing understanding of the economic risks it poses, has caused environmental, social and governance (ESG) considerations to rise up corporate agendas. This has resulted in a shift in perception, where ESG is no longer considered a risk to be managed, but rather is a significant driver that is informing company strategy for long-term growth. Traditional barriers to the adoption of more sustainable development, including perceived higher costs and a general lack of awareness, are being outweighed by the increasing importance of ESG in investment and procurement decisions.
As we know, when trees grow they absorb carbon dioxide from the atmosphere locking it away as carbon in the cells of the tree. The reporting of this carbon sequestration is often a source of debate with potential confusion and inconsistency. This often stems around when the carbon sequestration is considered. To help demystify this life cycle analysis can be used which breaks a product’s life cycle in stages. The standard used for this, BS EN 15978, can be broadly broken down into the following modules.
Module A dominates the life cycle emissions, particularly as we see decarbonisation in the operational aspects found in module B. Steel and concrete require a high-energy production process, but energy consumption for timber is also significant due to the harvesting, drying and sawing. Confusion with timber occurs as the amount of carbon stored within wood can be greater than the module A emissions and in some reporting is quoted as immediately carbon negative. This approach would mean that using timber excessively in a building is better for the environment – this is obviously not the case.
There are positives to sequestering atmospheric carbon within long-term timber projects as they act as a carbon sink which is beneficial to the climate. For example, over a 50-year harvest cycle in a managed forest a new tree(s), that has replaced the harvested tree, grows large and sequesters carbon from the atmosphere thereby achieving a carbon negative position. After 60 years of the building’s use, carbon is potentially released back into the atmosphere as the building is either sent to a landfill or burnt in a biomass boiler.
However, in 60 years, it could be appropriate to consider that carbon capture technologies will mean that no further carbon is emitted at the end of the life of the building. Consequently, the timber building remains carbon negative due to the carbon sink of the replacement tree(s) – steel or concrete cannot do this. It should also be noted that an efficient timber design, one which has reasonable grids and optimised design, typically has a lower embodied carbon than either steel or concrete buildings.
Accounting for sequestered carbon is a significantly debated subject, and there is much confusion and inconsistency surrounding it. Reporting sequestration alongside the reported figures of module A or a negative emission can generate the belief that using timber in excess is beneficial to the atmosphere. However when designed efficiently timber frames can be a much better option than steel or concrete frames.
At Ramboll we present our carbon figures in a clear and transparent manner so that clients can make informed decisions about the carbon impact of their projects.
At this point in time, timber currently can offer a lower carbon solution than either concrete or steel with timber having the opportunity to be carbon negative over a 50-year cycle.
If we specify and construct more timber buildings, this will buy us time against climate change to allow technologies to develop to an appropriate level until we can potentially utilise permanent carbon storage technologies or the expected lowering of embodied carbon of concrete and steel in the future.
Currently, timber is an incredibly effective and sustainable building material. However, it is equally important to understand that there isn’t an infinite supply, so attention must be paid to ethical forestry and timber sourcing to safeguard the future of timber as a material.
We currently have the understanding and tools to rationalise our design decisions with respect to the embodied carbon and, for now, timber buildings certainly form part of the solution in addressing the climate crisis.
For more information please visit www.ramboll.com