Built Environment Matters

Sustainable Buildings: PassivHaus, low carbon design and NABERS: Bryden Wood’s Head of Sustainability, Pablo Gugel, talks to Jaimie Johnston MBE

• Bryden Wood • Season 1 • Episode 14

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Learn about the key ways we’ll achieve net zero building using sustainable design and modern methods of construction. Check out this month’s episode of our podcast, Built Environment Matters. Bryden Wood’s Head of Sustainability, Pablo Gugel, joins Jaimie Johnston MBE. 

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Hello, welcome to Built Environment Matters. A monthly podcast brought to you by Bryden Wood, an international company of technologists, designers, architects, engineers and analysts working for a better built environment. Bryden Wood believe in design to value to cut carbon, drive efficiency, save time, make beautiful places and build a better future.

Jaimie Johnston:

Hello, and thanks for joining this edition of Built Environment Matters the Bryden Wood podcast. I'm your host, Jaimie Johnson. I'm head of global systems at Bryden Wood. Today I'm joined by Pablo Gugel, who's our head of sustainability.

Pablo Gugel:

Hi, Jaimie, how are you? I

Jaimie Johnston:

public? Yeah, great. Thanks. Thanks for joining. So let's kick off. Can you give us a bit of an intro to yourself your background and how you came to join Bryden Wood?

Pablo Gugel:

Yes. I'm an architect educated in Spain and I moved to the UK I think like 13 or 14 years ago, and I worked for a couple of years as an architect in Grimshaws, an old friend of Bryden Wood. And then I started a masters in sustainable environmental design, which is what changes everything from an architectural career into sustainability. And that led me to teaching I've been teaching in the UCL architecture Association and a real College of Arts work for 10 years at Chapman, VSP unintelligent afterwards, so that we basically was the what I got on my technical knowledge, and then I decided to move to Bryden Wood six months ago, I think more or less. The reason is because I wanted to explore new new approaches. And I found that when I learned about the Bryden Wood, this really interesting potential connection between modern methods of construction information sustainability, there's a real link there that we need to explore it. And that's what we've been trying to do for the last six months.

Jaimie Johnston:

Yeah, it's great. I come from an architectural background, I suppose that inherently you're sort of taught how to think in terms of integration, how to lead a project, that's quite an interesting way into it. So rather, from an engineering background, you started as sort of architect and came into it, perhaps you can talk a bit more about, you know what that means to us in terms of the integration. That link, as you said, between MMC and sustainable design?

Pablo Gugel:

Yes, that's actually important because when I started learning a bit of a sustainability, I realised that there are two languages almost as the architectural language, and there's the engineer language. And there's like, complete different knowledge, you need to have to be able to interpret both languages. So if you want to have an integrated design, which means that you have all the different subjects feeding into in the same direction in a project, there's a unique opportunity in Bryden Wood did it and that is that we have all the disciplines in one under one roof, we have architects, we have engineers, we have what civil engineers and building services engineers, and we have a sustainability and building physics team. So that means that that integration happens in a more natural way, you can get integrated design in normal projects where you have all the different members of a team in a room. And in those meetings, you can achieve that integration. But it is more natural and easier when you have all the disciplines in one roof. And I think the objective is to make sustainability, the glue, being at the centre of the conversation so that all these different disciplines learn in the language and talk about sustainability, and try to push in the same direction.

Jaimie Johnston:

Yeah, it's interesting, because we've talked on this podcast before I think about translation into different languages. So you're almost saying sustainability should be the common language. If everyone if everyone talks about them, whether you're an architect or an engineer, you're sort of heading in the same direction, at least it gives you a common point of reference and the sort of common common aim to achieve on every project,

Pablo Gugel:

I think so I think it's important that we learn that language and I think everything is going into this interaction, there's a lot of interest and pressure in sustainability to make more sustainable buildings. And I think we I think we have a very collaborative team. And I think collaboration is really important, because one thing that tends to happen in sustainability is that unless you start talking about it, in the early stages of design, it is really difficult to root it in in the project. So when we tried to do is creating an iterative process, a collaborative work, where at every stage is rearranges, your sub workshops with all these different specialists, and then at each RIBA stage, we do like a feedback loop. We've revised it and then the ambitions will revise the targets, we try to push harder. And that gives a lot of very useful information. There's a lot of like a cyclical feedback that I think is important for us because we need to constantly learn this is a lack of sustainability is a moving target, but it also adds maximum value to the client. clients want to understand what they are doing and they want to get that that kind of feedback. I think one of the That characterises Bryden Wood a the stability and belief is extreme within Bryden Wood is that we are a science based team. We like data, we like graphics, we like to understand how things operate, and we like simulating it. And we have like a wide range of technical knowledge. And that enables us to deliver all the different aspects of sustainability at a very highly technical level. So we can do from things such as operational energy and carbon, embodied carbon we can do for sunlight optimization, daylight, sunlight and glare in simulations, we can do things which are really specialised, such as CFD, and benchmarking, which is like the umbrella of sustainability in a way. So I think we have the capability of offering offering integrated collaborative and science based in design and projects.

Jaimie Johnston:

So it's a field that's awash with them, acronyms and terms. So even in that sort of last answer, there's quite a few terms knocking around, I think it's one of these things where perhaps people use them interchangeably, which may be for a while was sort of, you know, it was a, it was a direction travel, I think, now it's getting to the point where some of these things make a difference. So perhaps you can unpack some of these terms. So you've mentioned embodied carbon, net zero, carbon gets talked about PassivHaus, building physics, perhaps you can, can you start with building physics? Just to clarify that, and then we'll, we'll get into some of those other terms.

Unknown:

Yeah, I think building physics is an interesting one, because the way I see sustainability, sustainability is a bigger term. And building physics is a way of doing things to service the sustainability. So Building physics is basically understanding the physical concepts, then the concepts, but also the the maths behind how you can simulate and how you can emulate the performance of a building. And that can be calculating the energy consumption of a building over some period of time. And to the thermal comfort, you can simulate thermal comfort, you can simulate the daylight a performance of a building, or demand of solar radiation through a window. All of that is data. All of that is pure physics, essentially. But it's called building physics, because it's the physics that relate just to how a building performs. And I think there are lots of terms as you said, one of them that I mentioned is CFD, that's computer fluid dynamics, that that's one very specific one that that explains how temperatures and air movement moves within a building or around the building. Or you can simulate the winds or wind paths. And that's important to us, because that enables us to understand in complex geometries how temperatures move. So let's say if you design an atrium, which is a complex thing to design, what happens to the temperature, the lower level of the atrium? And what happens to that with the temperatures at the higher level of that, that space? How the air moves from the adjacent rooms into that space? How, how, how's thermal comfort, perceived? So all of that can only be done by a data driven calculations and science.

Jaimie Johnston:

Yeah, the speed of that is obviously getting quicker and quicker as computing power becomes cheaper and cheaper. I mean, I remember back in the day, you might have run some of these simulations, maybe once as part of a building control report, just to say, yeah, we've done it, it doesn't it doesn't, you know, exceed some of the the expectations, whereas now I guess it's much more iterative, isn't it, you can run those simulations that much more quickly, and feed it back into the design. I think that's a big shift that we've seen over the last few years,

Pablo Gugel:

Yeah, completely. And there are a couple of servers that enabled us that integration of and that is iteration. So we use grasshopper and within grasshopper, we use tools that they are called the ladybug and honeybee that enables us to simulate, for instance, different facade parameters like a window you value and you value the window size, then the prosthetics of the world, different orientations, all of all of that combined in one go. So you simulated them in maybe like a whole day. And then you got the best performing combination of all those different factors. years ago, that would take days of work. Now, we can do too much quicker, because there's technical capacity and software availability, which is Yeah, ready, ready for us?

Jaimie Johnston:

Yeah, so we're gonna kind of come back to that, because I want to talk about that on specific projects like The Forge but you're just working through some of these terms. Perhaps you can talk about passivhaus because I hear it used quite a lot. And I'm not sure it's, it's completely well understood out in the industry.

Pablo Gugel:

Yes, I think there's a growing interest in in passivhaus. passivhaus is a standard for low energy buildings that was, was born in Germany, and I think is quite well established in in Europe in general, and I think is picking up in the UK. And I've noticed that we've been preparing an article about PassivHaus soon and in doing that, they realise that theres a growing interest in the UK. And there's a heated debate about its suitability to achieve net zero carbon buildings which I will explain in a second. But essentially just to explain what it what it does passivhaus asks you for a very specific performance targets one of them is to achieve a heating energy demand of less than 15 kilowatt hours per square metre per year, which is really low. For people who are not familiar with with kilowatt hours is a really low energy demand, then it asks you to have a good overheating performance to try to avoid overheating. And if you have a cooling system, it also has to be low energy. And then the characteristic that defines it the most is that is its air tightness is really low. So that means that there's no air leakage through its envelope is so most thermal bridge free, and that makes a really airtight building that doesn't lose any heat. So there are multiple benefits from from passivehaus. The main one is that it's a well recognised a mark that achieves really low or ultra low energy and carbon performance. But there are other benefits. One is that then the occupants perfect experience or perception is really good because the the air quality is high, because you have a heat recovery system that feeds Fresh air. So the in the air is controlled constantly being replenished. But also the temperature levels are really, really good. So you don't experience overheating. Now there are challenges to passivhaus. One is that because it requires this very airtight envelope, additional insulation, additional overlaps of membranes to create that air tightness. It's more design is more expensive to design it but it's and it's more designed more expensive to, to to build it. And there's also some skill shortage. So you don't find many contractors that can design a easily or comfortably a PassivHaus building. And that creates a bit of a problem. The good thing or the good news for us is that because we are specialised in a platforms and dfma that's a really good solution to these challenges. Because the complexity of of the facade design can be resolved by by platforms, which platforms in itself, in its essence try to tries to simplify the structure facade and the facade design basically ordered all the different assemblies. And that simplifies the design simplifies the cost creates a reduces the programme, probably you can explain this better than me, Jaimie, because you're a specialist in the field. But one of the key aspects is that it facilitates that the labour can learn them the methodology to build it, so that that the skills shortage problem disappears. So yeah, there's this really interesting view at using dfma to resolve these challenges in passivhaus.

Jaimie Johnston:

Yeah, one of the key things about platforms is trying to get kind of manufacturing, industry levels of quality into construction. And normally those things are poles apart. So we work with me like much higher tolerances and construction, whereas platforms are trying to get much closer to zero tolerance if we can get away from it. And yeah, that that would instantly kind of help with things like air tightness. You made a point that I think it's quite interesting about the user experience. So it's now defunct, but things like code for sustainable homes. One of the criticisms was it encourages tiny windows and therefore, you know, very stuffy buildings, you make them so airtight with so little glazing to prevent overheating that. Actually, it's sort of heading towards these are dark, dingy spaces, but passivhaus doesn't doesn't lead you in that direction. So yeah, what it does in terms design, I think it's quite an interesting thing to to expand upon.

Pablo Gugel:

Yeah, yeah, definitely serve it. When you do passivhaus. Design, one of the things you need to look into is is overheating. And it is true that bill regulations, some of the standards in the UK to design a sustainable residential buildings, mainly, the big can create sometimes an overheating problem that but that's addressed by the passivhaus approach. One of the things I mentioned before I don't want to forget about is that there's a heated debate about passivhaus, which is, well, you know, there's a lot of pressure to be into design, net zero carbon buildings. One thing that passivhaus does really well is designing netzero buildings in operation. So basically be net zero will, again, related to heating, cooling, lighting, the operational side of things that passivhaus doesn't really care about what happens with embodied carbon. So the criticism from some people comes, or the other views is that passivhaus doesn't do anything about it. So it's not the right approach. But some other people say that actually passivhaus doesn't really affect the possibility of making a low carbon building from an embodied carbon point of view. So one thing that we've been doing at in the building physics and sustainability team is doing a calculation to try to understand The truth and then the technical and the reasoning behind this. And what is interesting is that it is true that if you have a PassivHaus, you have triple glazing and an mvhr heat pump additional insulation, and that increases the the carbon or the embodied carbon of a building, but at the same time, you have a reduced boiler size, you have reduced number of radiators, you have an reduced size of PV arrays, and you have a compact shape. By having a compact shape, you have less materials. So we did a detailed calculation of this. And in total, the embodied carbon compared to a typical building was reduced by 0.7, which is virtually zero. So that means that you didn't win, you don't lose effectively have a normal building from the point of view of embodied carbon, you can make it low carbon by just, incorporating all the other measures you would put into any other building like you would look into the specifications, try to use teamwork, try to use low carbon steel, try to use low carbon concrete, and try to make it as close to zero as possible. So from my point of view, PassivHaus is a good way to achieve net zero carbon building from operational point of view and also from an embodied carbon point of view.

Jaimie Johnston:

Yeah, it's interesting, you talked about the, it starts with a design process heading towards it, which is we've talked a lot on this podcast before about it's the same with design for manufacturing assembly or MMC. It kind of starts with the design process, you don't post apply this it starts it's quite embedded in the design process. So in that, in that sense, it's quite aligned, isn't it with the kind of aspirations of MMC, you're sort of heading in the same direction? Or it's another one of these things which is pointing in the in the same direction? So overall, better Building Performance?

Pablo Gugel:

Yeah, yeah, definitely. I think there's there are lots of synergies with between dfma modern methods of construction and try to make more sustainable buildings. And I think one of the key in discussions in the sustainability industry at the moment is net zero carbon in general. And I think there are lots of possibilities from dfma and modern methods of construction to make it more to reduce embodied carbon and operational carbon, I think, theres a growing pressure, because as you probably know the built environment is around 40% of the UK, totalling a carbon footprint. And there are bodies like LETI, RIBA and UK GBC, who are leading the discussion and try to, to to bring net zero carbon discussion to the centre of the of the agenda. And there's even a project to make a new building regulations item which is but set, I think, to try to calculate them, but the company doesn't exist at the moment, but I think his target is four to 2030. So there's clearly a direction and a lot of pressure to reduce carbon. And I think it's I think it's feasible. I think it is feasible in the long term if you use things such as a carbon offsetting schemes and a power purchase agreement, but I think it's probably important to explain that nowadays we just assigned me And so within the constraints of a building, it is very difficult to make a netzero carbon building. So what tends to happen is that you first try to reduce the carbon by a design means and then on the operational side, you need to pay to use renewable electricity. And on the embodied carbon side of things, you need to look for a carbon offset scheme. And again, pay for that. And the quantities can be substantial. So when you look at let's say, 20, like a tower building or like a 20 20,000 square metre building, you can be talking about a couple of millions of pounds to settle all that amount of of carbon. So it is possible, it is desirable, but it can be expensive. If If a If you leave the design issues until the end of the design process.

Jaimie Johnston:

Is it fair that net zero carbon people are generally at the moment they're more focused on the operational carbon? They're less focused on embodied carbon? Because it seems to still be quite hard to calculate the you know, the data is not necessarily there. Is that fair as it moved on?

Pablo Gugel:

From? I think it has moved? I think traditionally, yes, there's been definitely a lot of knowledge in terms of energy simulation carbon simulation in operation. And the industry has been growing over the last I would say three years in terms of the capabilities of professionals, but also the software's available to calculate embodied carbon. And the industry, I think, has pushed in the direction and nowadays, I think most architectural or builder services engineers, firms, firms, they have a an expert or person who can estimate to a certain degree embodied carbon. Now, it is true that there's some data missing one particular part of the data is MEP. So building services, there's not a lot of information. And that's one of the key challenges where you want to design in when you want to calculate embodied carbon. So we have lots of data about all sorts of materials, but not MEP MEP items, and is not a negligible quantity. Typically, the MEP requirement of a building would be 15%. So if you don't calculate that you're missing a big part of the puzzle, but I think in general, yes, there's a growing knowledge and an interest in, in in product governance in the industry.

Jaimie Johnston:

But it also it seems to, you need to know quite a lot about the building is quite specific. So travel distance of materials, so where you're sourcing the materials where you're deploying them. Again, all of that makes it more complicated, because you can't just model the building, you also have to think quite a lot about the construction process, the procurement process, all of those things. So that seems to also make it more complex or more building specific maybe than than some of the other parts that you might do.

Pablo Gugel:

It is it Yes, and luckily, there are a couple of software's available and that simplify all that complexity, because they have the right database and is arranged in a way that already includes assumptions for transportation distance, or for the amount of waste generated or to what happens at the end of the lifetime of a building in terms of whether the materials are disposed to landfill or they're recycled, etc. But what some of the leaders in the industry trying to do, and that's something that we have done as well as developing our own in house tool. So we use third party verifier software's but we also have a tool that can go into a lot of detail into those details like we can refine the transportation distance, we can refine the amount of waste generated, we can we find the the material use and and that's really important for us, because since we are specialists in design for manufacture and assembly, one of the things that we need to do is try to quantify the detail of how much transportation we're eliminating, because we we are simply assembling components somewhere else. So how much waste we are reducing because our our our, our buildings, they and they are much more refined, or whether the opportunities to disassemble a project building elements sorry. So that instead of going to the to to the landfill, we can recuperate that material and reuse it for some other purpose. So we have that capability. And we have been developing it over the last few months and years. But history is complex here.

Jaimie Johnston:

It just just to give a sense, have you got any examples of how significant waste and transport are particularly in terms of overall embodied carbon? Is it a couple of percent or is actually quite significant? Does it make a big difference?

Pablo Gugel:

It is not it just through the I mean, it is important to look at all the different aspects of the process. So just to give you a slight summary of how it normally works, you have the first part of the first phase of a of a whole building lifecycle analysis is the manufacturing. And that could easily account or amount for 60% of the total, they have a second phase, which is the waste and transportation, that could be just 5% is not a lot. But when you're trying to push through netzero carbon, you want to address every single bit and piece so that you reduce embodied carbon, then there's a second or third phase that is has two small parts, one of them, it's really important, and it's one of my favourite topics about embodied carbon , which is refrigens and I will I will explain a bit more about that in a second. And then there's the replacement. So in a building or materials, they need to remember it well not all of them, many of the materials they need to replace be replaced with steel and concrete, probably not. But all the finishes, they need to be replaced every 20 or 30 years of 10 years depending on the on the material MEP items, they need to be replaced every 20 years. And that means that they need to be remanufactured installed again. So the amount of carbon over let's say six years, adds up to a much bigger figure. And then the last part is then the end of life part which is when you quantify what happens if it goes to landfill if you reuse it if you burn it, etc. And just going back to the topic of refrigens, because I think it's really important. When we talk about buildings we always think about steel elements the structure the roof, the foundation cetera we can think about the MEP it is but most people forget about refrigens, because it's just what happens when the gas is released to the atmosphere Isn't he doesn't seem to material, but it has a huge impact, especially in buildings which are heavily cool like a data centre for instance, you can inspect that the refrigerant could have an impact of 15 20% of the total of embodied carbon. And that's a discussion that is a becoming more important the industry, the CDC released tm 65, which is a methodology to try to quantify the embodied carbon of MEP items. And they put a lot of stress in there looking the impact of refrigens , because this is really high. So we need to when we decide in building systems, we need to look into words, refrigerants we use, because they they can have a really high impact in the total of the whole lifecycle of a carbon of a building.

Jaimie Johnston:

I'm presuming that's going to have a big impact on how We design buildings, so particularly data centres, they're becoming more prevalent. Yeah, certainly, you know, lockdown has taught us as that reliance on good data infrastructure is becoming more important. So have you got any sort of thoughts on where that's going to start to lead us in terms of the design of some of these very energy intensive building types?

Pablo Gugel:

Yes, I think one of the key aspects is that when you design a refrigerant with a low global warming potential, that has a knock on effect, the first one is that the efficiency of the cooling system drops, which means that you either have to have more chillers and more equipment essentially. So that increases embodied carbon on on one on the other side. And that also affects the design of the plunger that mean, that can mean that in the sizes bigger, so that then knock on effects on the architectural design as well in terms of space planning. And they're one of the downsides as well is that apparently the refrigens that have a low lower global warming potential, they are more subject to to burn. So and I know that we all know that in the industry. Now, fire protection is a sensitive subject. So we need to be also aware of that. But I think one of them that the smart way to address it is to try to find ways to create frequenting opportunities looking at maybe thermal labryniths, pre cooling, overnight use and thermal mass, any kind of means to try to reduce the active cooling and try to facilitate if possible, a passive passive cooling of free cooling.

Jaimie Johnston:

Yeah. Which, which then leads on to material choice. So one of the things I was really keen to talk about, I know we've spoken about it previously is the ongoing steel versus concrete versus timber debate. So I know there's a sort of knee jerk thing that says, well, timber, must must be the right answer. But it's a lot more complex than that. Perhaps you can unpack that a bit.

Pablo Gugel:

It is complex, it is slightly controversial, because I think when you open a newspaper newspaper, there are always news about a sustainability and construction. And you can see lots of articles, talking about timber constructions, like if it was a holy grail, like if it was the resolution, but it's actually complicated. So concrete, it is true that concrete has accumulated for most of the embodied carbon emissions over the last decades, because it's a material that is carbon ntensive. But the positive hing of concrete is that robably due to that ongoing ressure, the industry has been hifting and releasing products hat have low low lower carbon, ot low carbon, which is omething that is still at least n the UK cannot do yet. So it till is really carbon i tensive. That's partially due t the process of manufacturing. A d the way to reduce it would b to use electric electric arc f rnaces, which, which are fed b renewable energy, if p ssible, an increase in the p rcentage of recycled content. B t that's not available in the U. So you need to source it f om Europe. And complicate c mplicates things. So that m ans that we need to wait p obably a decade or two, I d n't know for how long but p obably for a long time until t e whole industry in the steel i dustry gets up to speed in the U, when it comes to low carbon m terials. I think concrete has b en faster than that. Now, when i comes to timber, yes, timber c ptures a carbon. But what most p ople don't talk about is what h ppens at the end of the l fetime of a building. So just e plain you the process of how t mber captures in carbon, when a tree grows, obviously captures c rbon in its different parts of i s body, then you cut it b cause you don't use the b anches, the leaves and the r ots. So you probably release 5% of its carbon emissions when y u chop a tree, and you're u ing just half of it. And t at's stored in your timber b ams and columns and floors, e c, until you demolish your b ilding. And that time, d fferent things can happen. If y u release them timber into a l ndfill, it releases carbon, so y u lose the positive benefit. B t it also releases methane. A d missing is more he has a m ch higher global warming p tential impact than than carb n. So he has a really nega ive impact. Now, there are ways to attenuate that one is that in some landfills, you can actu lly carbon, capture the carb n. So there are ways to do it. nd the most efficient or the est way to do it would be to t ke that template and reuse it. o that puts a lot of pres ure on the design. We need to d sign for buildings that get dism ntled easily. And that can reus the material for future proj cts. But it's easier said than done. So one of the chal enges is that something exci ing we can do. But clients they need to to to be on the same line. They need to be clear abou whether they can have the capa ity that so that in 60 year time they can say well I'm goin to demolish my buildings. But hese pieces they're going to b used in a different way, that s really difficult to say, is a really difficult commitment for client. So that completely dism ntles the potentially the bene it of timber, there are othe sides of the discussion. Sorr, I'm moving on sending a lot f this, but I think it's impo tant to spend that timber has ome fire implications, it has ome implications of coor ination, because you have down tand beams that they are dee er. So you can coordinate a con rete slab or frame with a steel rame slab in easier probab y, and the other sort of the thi gs that people don't talk ab ut, which is the timber release a volatile organic compoun s, which are bad for your he lth. And that's somethi g that doesn't happen we with st el and concrete, and one of the hing is that timber is solid m terial. Concrete has thermal mas, we know the thermal mass has lots of benefits in terms of the mal comfort. So the equation is omplex is not a simple dis ussion. So you need to acc unt for many things. And it' not like timber is better. Wel, it depends. Concrete can be etter than timber. And steel can be better than timber, dep nding on the characteristics and the specifications of those mat rials.

Jaimie Johnston:

Yeah, just I mean, in my head, it feels like like all these things, they're all very complex, we need a rich mix of things moving forward, it feels like the route to low carbon concrete much quicker than steel. I mean, all of the big steel manufacturers seem to be on the path of electric arc furnaces, but it feels like that's quite a way off. It feels like there's quite a lot of technology for concrete, there's on the starting blocks that feels like timber is a very good interim while we get there. Could we get to the point where concrete makes more sense sustainably than than timber? Or do you think timber will always have an edge if we can sort out sequestration?

Pablo Gugel:

I think if we solve the sequestration and the carbon capture, it will always have the edge. But yeah, that's that's a big problem. I think in the meantime, we can reduce embodied carbon from concrete by big proportion, to the degree that it can compete with some timber structures and with the best of steel structures. So I think when we look at embodied carbon, we need to look at a on a project basis, we cannot say that a steel is better than timber or concrete is better than steel, we need to look into the characteristics of the building the grid of the building on things such as semi coordination, the potential problems of overheating, take all of that in the equation and say, Okay, I think probably makes sense to, to go down this route and select this material.

Jaimie Johnston:

Yeah, the other thing I mean, no one's ever answered this question to my satisfaction. Do we know how much timber is available to build with inkling that you go, I bet we couldn't grow enough timber to make every building we ever need. But I don't know whether that's just a completely. That's just my perception of or whether anyone's actually looked at it properly? Or, you know, where's it going to come from? We can't grow necessarily as much in the UK as we'd need. I don't know if you know, anybody

Pablo Gugel:

I will leave you disappointed? Unfortunately, the answer? So yeah, in that's actually a really complex subject, because you need to, the right way to do it is to source timber is to source them from sustainable sources. And not all the forests in the world, they are certified. And that already limits the amount of timber that you have. But it is true that if all the if all the buildings in the world, they decided to be building timber, I don't think there would be enough timber. And on one hand, we need to look at how we make business which are more sustainable, but at the same time, we need to allow for forests to grow, I think, disagreeing pressuring in the sustainability debate to increase the mass of trees. And we cannot just if we fight in the opposite direction. So yeah, there are side effects directly impact on ecosystems and their global and yeah, climate balance of all the different countries, etc. So it is complex, and I don't have that clear answet. But I also think that we cannot build all the buildings within the in one go. This this note enough thing, the problem.

Jaimie Johnston:

Yeah. Okay. So you know, you slightly more me, if anyone's listening and has any answers, or knows of any research that's been done, we'd love to hear from you. Because this is a huge topic, isn't it? And yeah, we could talk about this all day. But just that complexity between those three material types is there's so many unanswered questions. And it's such a tricky thing to get your head around. But you know, the industry needs to get some answers to these questions fairly quickly, doesn't it? So anyway, any pointers will be gladly received. So moving on a bit. So we've talked a bit about the Forge. Certainly, this podcast we've touched on it. That is the UKs first net zero commercial building. We're delivering it for Landsec at the moment. It's the first project using platforms, perhaps you can, you can talk a bit about the design process and the metrics we're getting on that building and what that means in terms of net zero how that's being achieved. Etcetera.

Pablo Gugel:

Yeah. So yeah, as you said, is the first commercial building in the UK to align with the UK GBC framework. For net zero carbon that means that it is net zero in operation, and is net zero in for an embodied carbon point of view. And that's important to highlight because there are many buildings out there that claim to be net zero, but they are just netzero at one part of the equation regulated energy only, or sometimes the whole operational energy. But I don't think there's any commercial building, this will be the first one in the UK to cover a whole spectrum. And one of the reasons one of the one of the things that we did to achieve a low carbon building, and then do further steps to become netzero is to adopt NABERS design for performance scheme, which for people who are not familiar with it, you probably will know that we in the UK, we use pattern to calculate carbon emissions of the regulated side of the energy. But there's some well known and established knowledge that and that pattern doesn't define very well how the building operate, there's a performance gap. So there are all the schemes such as CIBSE TM 54, are now neighbours that try to define the performance of buildings in a more accurate way. In doing so, what tends to happen is that the more accurately you are, the more carbon emissions you you calculate, or you estimate the more energy intensive your buildings become, because you're closer you're closing the gap to help buildings operate. And that means that you need to to reduce more carbon, you need to reduce more energy, and it's a bit more challenging and requires more work. And that's something that we have done for for NABERS, we are pioneers in NABERS, we are advocates from NABERS, we want more buildings to be done using this NABERS scheme because it's more accurate and is more representative of the performance. And in doing that we have reduced the energy, not just the small parts that are addressed by building regulations, but we have looked into the lived state equipment, each single part it's single bits and piece from the energy consumption of the building that has made a huge difference. Now the embodied carbon side of things. The greatest achievement is that when we started with a calculation that we did we in coordination and collaboration with candles is that we reduced 19.5% of the embodied carbon by using DfMA that's a lot that's a lot of carbon just by using a platforms based approach. And it's great news for us it's good news for for the industry in general, because it shows that it can be done and there has a lot of benefits. And then once we did that, the design evolved and we kept on looking at specifications and other ways of reducing embodied carbon and we reduced from 19.4 to 24% which is a quite a lot. So, what happened after that is that submission before when you first you tried to push to reduce embodied embodied and operational carbon and then you need to use a power purchase agreement which is renewable energy and pay to offset so that was the last part so that we we can claim that the building is netzero carbon. And there are lots of interesting exciting strategies that we put in place to to reduce carbon and I think the most the general concept is that this is a lean design. So in doing a in decent DfMA, we have tried to simplify the structure we have tried to simplify the facade in the frame, we have eliminated suspended suspended ceilings in most of their spaces in the building, they are not needed. So basically the their design approaches eliminate what is not needed. If you eliminated you reduce carbon by from design. And we have looked at then ways to be low carbon by selecting concrete that has a percentage of of cement replacement. So basically, you're eliminating cement by using other material. In this case, it's called ggbs. And we have looked and what if we use a recycled reclaimed raised floors there's a lot of because it's an office building, there's a lot of a raised floor surface and we are using reclaimed raised floor that that reduces carbon by quite a lot. And all the important strategies that did in the building is designed for the construction. So it was mentioned before, it is important that the buildings can be disassembled so that rather than throwing things to the landfill, you can reuse it for some other purpose in the future. And then from the operational side of things. So there are a few lessons learned from this building. The first one probably one of the most important says that NABERS creates a huge opportunity for us to close the performance gap. Another one is that the concrete that was originally specified is self compacting concrete and self compacting concrete is more carbon intensive. So what we did to try to compensate in this way is using GGBS or another cement replacement but we need to find opportunities to avoid using self compacting concrete if possible, and that's a one challenge that we need to address us as designers. Another interesting thing to look into in general is that when you design an aluminium elements, if you use powder coated aluminium is less capital intensive than a conventional anodized aluminium. And that's what we have to use for, for some elements of the facade. And I think one really important thing to always look into is the importance of sourcing. So um, in in the structural approach, we have some micro columns, which they are tubular shape, and they are EU sourced. So I think it's a bit more complicated to sources from the UK, but in sourcing them from the from Europe and the percentage of recycled content is lower in the in the UK is by you can start assuming that is 20% in Europe is zero. So if you source some certain steel materials from the UK, you havent mentioned that, and aluminium in this case, many of the aluminium materials that we use that we specified, they came from Poland, and Poland depends a lot on the coal, which means that the embodied carbon of all the materials there are always more carbon intensive. So it is better to look into other countries for for your aluminium. So there's always something you learn about it. And in the forest, there are lots of interesting lessons lessons learnt

Jaimie Johnston:

during those numbers 24% reduction embodied carbon, that's a, that's a huge step forward. But what you're saying is over time, obviously, one of the benefits of platforms is you continue to continue to refine them, you continue to get these things to be better and better. So yeah, we'd hope that those figures improve. One of the things you mentioned was offsetting, but you you need to do that almost as a last resort, I guess people might think I can just offset this, but you go, Well, there's only limited capacity in the grid for offsetting, not everyone can do it. You want to do that, you know, almost as a kind of last resort once you've designed out as many of these things you possibly can to try and limit that that pressure on the the offsetting part of the grid. Is that right?

Unknown:

I completely agree. And I think one of the reasons is First, you need to be honest about your design. So you need to design buildings, which are at low as low carbon as possible within the possibilities of its design. And only then you offset that will make your project a bit more honest, from my point of view, from my current point of view, but also at the same time when you've set you need to pay. And as I mentioned before, the constants that you need to pay, they are non negligible, you can be talking for a large project, we can be talking about millions. So when clients hear that you designed a building, and you don't care about reducing measures, and all of a sudden you can be the figure, hey, by the way, you need to pay 2 million pounds. That's obviously not good news. And the carbon prices are increasing and are likely to increase. So yes, probably you don't want to give that kind of bad news to your client, you want to reduce their carbon, the carbon emissions and operational carbon emissions from design opportunities, which are free, essentially.

Jaimie Johnston:

So it's very safe for clients listening, it's better to spend more money on design, and less on offsetting Just saying. Perfect, just conscious of time now we need to, I guess, wrap up quickly. But yeah, we would like to ask guests what their sort of view of the industry looks like over the next 5-10 years. Obviously, it feels like, yeah, we've made big inroads with the Forge. For all the reasons you've talked about. There's obviously growing acceleration of interest in this topic that the data is getting better, the software is getting better. Where do you think we could be in 5-10 years towards sort of, you know, making some really big inroads into into dramatically reducing embodied carbon and operational carbon in the built environment.

Unknown:

I'm optimistic in general person, but I'm optimistic in also about the industry, because there are lots of people pushing in this direction, you can see lots of building which are fighting to to get the right headline lag, this is the first building that is net zero, or my building has reduced this amount of carbon emissions in operation. And they said through fight by clients to be at the, at the end, Leading the Leading the game, essentially. And I think there are lots of bodies like a GLA LETI, RIBA who are pushing in this direction. Billing regulations are changing in the right direction, although the good push a bit more in for you is I think that's what most people think. And so far, from that point of view, I'm optimistic and I think in five years time, designg net zero buildings would be quite common. And hopefully, in 10 years time, we'll be talking about huge changes in the industry. One of the key differences that will completely change things is that the ingredients being decarbonized. And that will affect the materials that will affect the performance of the buildings. And that's that's good news, in general. So, in general, I'm optimistic , although when you look at the outside world, it thinks related to global warming a bit less optimistic and problematic that I guess it's a different story.

Jaimie Johnston:

But it's always needed as a stark reminder, isn't it? We have to get this to be business as usual. We have to move beyond the kind of, you know, the nation's first the world's first and into kind of Yes. Yeah. Almost needs to be a strange event if someone doesn't designs a building that isnt net carbon zero? That's where we need to get fairly quickly, isn't it?

Unknown:

Yeah, yeah, absolutely. I think we need to do our part in the construction industry. There are lots of different factors in the when it comes to reducing the impacts of global global warming, and we need to do our fair bit.

Jaimie Johnston:

That's great. That's probably all we got time for so we'll have to wrap up there. We could obviously have talked about this for a lot longer. But yeah, as I say, if anyone's got any further insights, further research that we can have a look at then, yeah, wed love to hear from you. So Pablo thanks so much for joining me. And yeah, enjoy the rest of the day.

Pablo Gugel:

Thank you very much.

Jaimie Johnston:

So thanks so much for listening in and please join us next time for more Built Environment Matters.

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