Platform on concrete and steel in construction
In this edition of Concrete & Steel Construction, the podcast, two guests join us: Yves Terneu of Aalborg White and Bernard de Troch of the renowned architectural firm Conix RDBM. Topic of discussion: can white cement in a sharply reducing CO2 market?
The construction industry plays a significant role in global CO2 emissions, making it critical for architects and designers to choose low-carbon strategies. How does white cement concrete frame this, and how does it differ greatly from classic gray concrete? The gentlemen come up with surprising insights, discuss unique application possibilities and don't leave out the unknowns either. In short, an interesting talk for anyone who wants to work with white cement concrete and still be able to meet all the sustainability and CO2 reduction objectives.
[00:04] Welcome to Concrete & Steel Construction the podcast. My name is Roel van Gils, I'm the moderator today. And at the table are Yves Terneu from Aalborg White and Bernard de Troch from CONIX RDBM.
[00:18] Gentlemen, please introduce yourselves.
[00:21] Thank you Roel for the introduction. My name is Yves Terneu, I work for Aalborg Portland. Aalborg Portland is a white cement manufacturer that has worldwide productions in some 70 countries,
[00:35] operates and we make, as mentioned, white cement.
[00:39] Okay, thank you very much. Bernard?
[00:41] Thank you, Roel. I'm Bernard De Troch and I work for CONIX RDBM Architect. We are a large, medium-sized architectural firm, operating in the Netherlands as well as in Belgium, and 65, 70 employees who draw, execute and deliver for us.
[01:04] Thank you very much. Gentlemen, or Bernard should I say, what I am wondering. What are the main reasons for choosing white cement concrete?
[01:13] Concrete is a, let me start generally, concrete is a very grateful product. It is almost indispensable in construction. And the fact that it can also be in white gives a very luxurious static appearance in our buildings. It has many advantages.
[01:27] To heating, a black building heats up very quickly, a white building reflects a lot of the heat. So that's to the interior and to the interior quality a big advantage.
[01:39] And of course luxurious appearance. I always compare formerly civilian houses, both in the Netherlands and in Belgium we had a white plaster. And that gives a majestic look. And we still try to get that today.
[01:53] And concrete is a very easy application to apply there.
[01:58] A very rewarding application in that as well. Often people also tell us that white concrete building has a certain look. But it also provides some security.
[02:11] It's also a bit lighter than other buildings in a lot of cases.
[02:16] Yes, now of course we've heard some advantages, are there perhaps some disadvantages? Do I look at Bertrand in particular.
[02:22] There is no problem though. Disadvantages, yes, it's maybe a little bit more expensive because it's very long lasting. And Baton is good for 30, 40 years, so it's a little bit more expensive.
[02:34] But to maintenance, yes, I'm going to go back to orders, because it's such an obvious product. Cons, it also has to be cleaned. On a white facade, you can see the markings of dirt or precipitation under villages and so on.
[02:49] That dictates some prudent intervention or maintenance. To architecture, we can reduce the risks. But to cons, it's a solid product. If you compare it to others, if you go to natural stone, we have to import from far.
[03:03] It also gets dirty. Steel is a little more sensitive to dents, to damage. Concrete damages very hard, or you have to pack really heavy already.
[03:14] Bernard talked about 30, 40 years. I think, if you look at the Pantheon in Rome, which has been there almost 2,000 years, also based on concrete made. There you see that concrete does last a very long time. White concrete has, or colored concrete, I'm going to say more about that in a moment.
[03:30] White concrete, of course, like any other facade, is going to pollute it. Are you in an urban environment, where there's a lot of soot from the cars, you're going to see that on the facade. Are you in a wooded area, it's definitely going to be green.
[03:45] But very easy to clean, because you have a very good surface that you can go and clean perfectly with a home garden and kercher, I'll call it. Are you going to do that every four, five years,
[04:00] then you're back perfect with a very nice building. There are lots of good examples there of buildings that had been there for forty years where a part has been added, where building owners are like yes, I want identical color.
[04:16] There we said of yes, clean the first part, even that in 30, 40 years and just make new white concrete again and it's perfect.
[04:23] But really with home garden and kitchen equipment, you say?
[04:26] Really, with an ordinary normal kercher, certainly no heavy industrial systems needed on that, because then you're going to have another finishing grade. Just very simple, home garden and kitchen kercher, so to speak.
[04:41] Okay, thank you very much. Yves, how is white concrete actually made?
[04:45] White concrete is made from white cement. You're going to have the most beautiful result with that. White or colored concrete also, because we talk about white concrete quite often here, but also all the colored concrete.
[04:58] We're here in the Netherlands, suppose you guys would like to make a very nice orange concrete, that's perfectly possible. And then if you're going to do that based on white cement, you're going to get a very nice stable color and a uniform color there.
[05:12] That's because of the properties of the white cement. White cement has almost all the ferrous parts removed from it and therefore you're going to be able to use all kinds of color, or most kinds of color pigments perfectly there to make a whole
[05:29] nice homogeneous color of it. Okay, thank you, interesting. Bernard, does constructing with white concrete require additional considerations?
[05:40] Yes, each product has its own applications. I was thinking about that later, if you would develop organic facades with round shapes, then concrete is more difficult, the formwork is more requirements imposed.
[05:55] So from the moment you make a choice to a material you have to respect certain rules of the game. And that is the challenge of every architect to find an optimal combination ahead of that. So indeed, but I also pointed out, concrete is a very grateful product and almost indispensable
[06:11] to build. As Ivo also said, the pantheon stands for 2000 years to make such a dome, there is almost no other way than with concrete. Hence, even in the future, concrete will still have a very high added value or almost endcontournable
[06:25] is. We want to make buildings that can be used for different applications. Not just residential, not just retail. And then concrete is a very useful product because it can encompass all applications and
[06:39] can also allow multiple uses in the future. But yes, those are the rules of the game you have to know and then it's optimal. That's where
[06:47] the architects for. Yes, you mentioned some examples of course. Do you yourself have any recent examples of projects that we can admire for example in Wilmerton? Yes certainly,
[06:56] it's because I know Yves so well. Balconies is a very standard product that we always do in white, that gives a visual accent. Now in Nostende our
[07:08] facades, on the coast that is also radiant, if there is a white concrete facade for high-rise buildings is often applied. Or they architectural plinth, that will be there in concrete and then we can combine that with masonry. A standard product, again, I think we need concrete for a long time to come.
[07:26] have and CO2 we do have to try to reduce or offset for that.
[07:32] Okay, maybe a nice bridge naive.
[07:36] Yes, indeed. CO2, very important topic right now. Alborg has been working for years to start limiting all possible CO2 reductions teismaterial.
[07:59] That clinker that then the white cement is made with is also going to be reduced. For example, we have new our D-carb, which is already 15% less and even compared to other 36% less in terms of CO2.
[08:14] Also from governments, from things that we certainly have to comply with now, but certainly 2030 and 2050.
[08:28] So we are also working on going to capture our entire CO2. So we're going to capture the CO2 in the chimney, we're going to then liquefy it and work with leatherliquid, who are then going to be able to provide other purposes with that product as well.
[08:54] What are actually the biggest differences from traditional gray concrete, Yves?
[08:59] Well, gray cement-based concrete has a different look, has a different appearance, also looks gray,
[09:18] is used for all structural applications, all the basic elements that you need in the concrete in the building. White concrete or colored concrete based on white cement is then a little bit of a change in that. White concrete based on white cement is always going to stay white. To give you a
[09:33] example to give, and some architects dare to do that sometimes in a building. Concrete base of gray cement there pour a bucket or a glass of water over it then you're going to see that that turns a very dark color.
[09:47] Your light gray concrete as you know it is then going to turn very dark gray that is the effect of that water on that concrete. With white cement again as I said later because all the ferrous parts are out of it,
[10:02] you're not going to have that. That's going to stay very white. So on rainy days you're still going to have that very white, radiant building.
[10:11] Okay, do you recognize that, Bernardo?
[10:13] Yes, absolutely. I don't think we are going to suggest facades of gray and concrete to clients. That's good for infrastructure works, motorways, bridges. Even there we see white concrete being used if you want an eye-catcher. As architects we then have the ambition to put something beautiful where it is pleasant to look at.
[10:32] Gray concrete is not suitable for that. The fact that white cement is already added also puts an additional requirement towards finishing, towards a neat formwork. And then a contractor or an outverder also knows, oh, we want to get something nice here. That's not the intention with the gray concrete, that doesn't work. That's subtle.
[10:55] that doesn't work. Subtly, no. So it also requires more constructive or more higher requirements, say, during assembly, during execution. That's why we're so proud of it,
[11:00] white cement, everybody hit motivated, white concrete, everybody put their best effort, but we know, this is going to be the end effect. And then there's an overlap, concrete has a load-bearing function, so it's already used in the shell construction, but we don't want that... That's a visible element of the load-bearing structure,
[11:17] and white cement helps to give that the attention it needs and that we don't get into the appreciation of that of, hey, something happened here to stay and be attractive. Yes. To stay beautiful
[11:32] for years and indeed from the first time it's good if you make a nice white concrete, from the first time it's going to be perfect. If you take care of that properly and everybody takes their responsibilities,
[11:48] then that's also not going to be extra difficult than, say, making gray concrete. No, it's all the same. But of course you have to give proper attention to it because you want that one beautiful material or beautiful panel immediately right for the next 30, 40, 50 years.
[12:10] And much longer. And much longer still. Yes, if I may chime in, because because of that attention from the beginning it is indeed pure and then we come to a little prefabrication as well. Concrete becomes
[12:22] poured in conditioned factory halls. If you want the groomed finish at brick or metal on a job site, it's done on site. And there you have more risks. You have the weather conditions
[12:37] not under control, you don't always have your people... You also have to achieve it at the workplace. Concrete has the advantage in that that that is made in a factory and then was assembled on site all at once. And so that has a quality guarantee.
[12:52] It can also be repeatedly finished cleanly and correctly in the same way every time. The drip noses, if you made the detail once, that balcony can be repeated, built and assembled a hundred or two hundred times.
[13:05] So you have a quality guarantee, an aesthetic guarantee, which is a security as an architect to get an acceptable result at the end.
[13:13] Is that also an argument precisely for choosing white concrete or constructing modular elements? Definitely.
[13:18] A combination of, modular certainly because indeed the repetitiveness is there. If it has to be aesthetic and visible, go ahead and make it in white concrete.
[13:29] In fact, it is becoming a necessity. The number of workers in the yards are becoming very scarce. And it's almost a necessity to try to go from in factory conditions and from performance in the yard still being limited to an assembly work.
[13:44] The elements, the components arrive from a secured factory environment and those are just assembled. And that's an advantage. Yes, almost inevitable.
[13:56] Urban environment it is also increasingly difficult to find space to go and make that yard complete. As a result, it is often very easy to have a number of trucks with
[14:09] the elements on that and then just assemble. Because how do you embrace in a contemporary
[14:17] design carbon-free, low-carbon elements? Super important answer. Before, actually is
[14:27] it an obvious question, but formerly the question limited to the architects, say yes, what is it going to cost? How do you determine the price? Today we absolutely have to go there and we are working with that to say not only, what is it going to cost, Mr. Construction Weather, but what is the carbon footprint? And also
[14:40] there, and then you feel that the equation as an architect, you don't have any ready-made solutions. But you have to be able to be able to say to the construction weather from in the beginning, approximately, what is that going to cost? And what are the CO2 emissions? We can't go around that anymore. And so the question of measurement states and unit prices are
[14:58] become obsolete if you can't directly add CO2 emissions there. And so as an architect we give a comparative study there by getting bimon designs and quantities out in time. And the challenge actually there is not great. Instead of saying what is the
[15:13] cubic meter price of concrete, what is the cubic meter emission of CO2? And there we get then let's be honest there we as architect are obviously also stimulating party but we look the challenge lies with Yves. Yves has to make sure that that concrete and
[15:27] are the cement still remains durable and it has already been cited that also the government imposes rules and I also say for us as architects the building weather is also asking the party in that because
[15:41] I put you right out of the link developers get favorable credit terms if they can demonstrate that a building is sustainable or look for a certain co2 emissions from that that point of view the challenge just becomes an obvious one guys
[15:56] tell me what is the co2 emissions that applies mainly to belgium I think or is that also an op is
[16:00] european europe and certainly in the Netherlands you are much more advanced on that point if I may say so compared to Belgium at the moment. The MKI calculations have been going on for years,
[16:14] whereas with us those are still kind of only now coming out fully. So no, certainly also in the Netherlands.
[16:21] We look over the wall to see how those calculations are done in the Netherlands. There are already databases for that, comparative studies. Because obviously we have to have an objective parameter. An estimate price, there are prices from databases for that. But for a CO2 emission, those products,
[16:36] and then is that certified, can we move forward on that, what does an architect base that on? And indeed the Netherlands is a little further ahead on that. The same thing for nitrogen emissions. You can put a yard silence if the nitrogen emissions are too high. We are not that far yet in Flanders.
[16:50] Fortunately, I almost want to say.
[16:53] For the progress of construction projects, indeed.
[16:58] The tuition money is paid in the Netherlands.
[17:01] Can we still come back to the production of white cement concrete? In terms of targets, what exactly are you guys doing to reduce CO2 emissions yet?
[17:16] As I pointed out there a moment ago, we're trying to start using as many materials as possible such that to start reducing CO2, so to start reducing the clinker number.
[17:29] We do that with, for example, putting limestone in there. In one of our applications, that's about 16-17% that's in there, so you already have that gain immediately.
[17:41] That's one. Meanwhile, there are a lot of other things we're researching. Second, as I touched on that a little bit later, the carbon capture and
[17:55] storage factory. That's in fact, you should almost imagine that a plant is as big as a cement plant that's going to be next to it, which so convert that entire, yes, from gaseous to liquid. So that's what's going to happen. As a result, we're going full CO2, outside of transportation of course,
[18:19] but are we going to have a completely carbon-neutral cement within 2-3 years.
[18:25] Yes, that was my next question indeed, from within now in 2-3 years.
[18:29] Within about three years, that will go. The factory since six months, they are building there. Where is your factory actually located? Our main factory is in Aalborg,
[18:41] Denmark. We are right on the water there, so we can ship everything by big ocean-going vessels to all the different locations where we have that. So that's very easy. I then want to
[18:53] just continuing very briefly on your question of what else do we all do. We have a surely state-of-the-art plant in Denmark there. And the residual heat from our furnaces and so on is used to supply households in Aalborg city, for example,
[19:13] to start heating those. So we are very inventive about that, also for years. A second example is the water of our quarries where that gallstone is extracted. Which is 9 degrees cold or 9 degrees cool all year round. And that water is used as water for air conditioning in various industries.
[19:44] Already in a hospital about two kilometers, 2-3 kilometers from the factory. So that 9 degree cold water is used there to start supplying that air conditioner with water. Especially in the summer period where tap water is somewhere between 15 and
[20:04] can be 20 degrees, that makes a very big difference. When I look back at, briefly at
[20:10] Bernhard look. Bernhard, do you anticipate a greater preference for low carbon products, cement end products in your future projects?
[20:18] A good question, but let me be honest. As an architect, it makes the end result important. And whether a lot of CO2 comes out or not, actually the result has to be there. And I think the biggest pressure is going to come from the financial corner, where that CO2 is going to be penalized by adding a supplement to cost price on that. And I am absolutely supportive of helping Yves to make sure that that cement cost or poor is going to be produced. But I don't turn the knobs there.
[20:52] I just hope I'm going to be able to keep using cement and concrete because it's so indispensable. As architects, set that to enable us to make sustainable buildings. Look at it the level of a building. Buildings in themselves should also be sustainable as a whole.
[21:08] And cement is 2% of all building elements in there. So let me say, the question is not only to IEVE to make low-CO2 building products, but also that the shop should be low-CO2. We get difficulties, for example, to sell aluminum, or to use it as a facade finish,
[21:26] because there is a very heavy sustainability footprint there as well. There the solution is circulating and recycling. The hang out is everywhere and we are a partner in that. I'm not going to be able to eliminate concrete,
[21:39] also don't want to cut, let me be very clear there. And I hope it remains affordable. For me, the building has to remain affordable, and then of course there comes a pressure there from the building owners. Of guys, everything is getting more expensive, we have to push some more sustainable. For example, let's have the
[21:53] grant buildings a longer age. And that means that as a builder says, look, instead of a ceiling height, I'm just saying something like 2.70 meters right now, let's make the baseboard standard at 2 meters, 3 meters, so that we can make stores there as well.
[22:06] And that that can still be such an application later on for residential construction. And that means that we have to think longer term, both as an architect, also from the concrete industry, to reduce the carbon impact, but also for the building lakes of people.
[22:19] We all have a mission for future generations. Is it going to be cheaper? No. Let us think along and we are fully engaged. Hence this conversation to convince us of that.
[22:33] You mentioned a number of arguments. Efficiency, speed, quality, high quality, durability. We haven't talked about fire resistance yet. Perhaps we can pick up on that.
[22:43] I think Bernard is quite qualified to go and explain that as well, but we all know that concrete has a very high fire resistance.
[22:54] Absolutely, absolutely. What happens there, for example, is the facades. The facades, if you do them in concrete, both exterior and interior, you can pack the insulation between the interior shell and the exterior shell.
[23:08] Today we're doing that with polaritanium, which should go to rock cavity, but because you're working with precast e elements, you can prevent that fire penetration between in the cavity, by lifting those elements off relative to each other.
[23:20] That's an exercise. We are also trying, we are building very many stoops today. The buildings are super insulated to not give off heat output. Does that mean in the summer the buildings heat up too much?
[23:34] And I think, that's a whole other discussion, but we have to go to a balance there that the insulation doesn't become too much. We're getting to 30-centimeter crap packages now, that facade construction is becoming almost impossible to do.
[23:47] So there are advancing insights there as well to optimize that. Fire spread is an essential element again, whether that's solved in concrete or with other elements, there are always solutions.
[23:59] But concrete is indeed non-combustible and may that fire spread, there's one less concern there.
[24:04] Do you guys notice that too, that that's precisely why that's chosen?
[24:08] Absolutely, if you see, worldwide a lot of architects are taking advantage of that, to indeed show those exterior shields, those façade elements and those balconies and so on, to show all that in that concrete.
[24:26] So indeed we experience that globally as well.
[24:33] To that, could you perhaps finally name a nice reference project in white concrete?
[24:39] Yes, I think OCIE in Ostend is I think a very nice example, Bert. Yes, wonderful.
[24:44] Ief, you keep going on in my mouth, that's one of the bigger projects. We've already done four phases, 50,000 square feet each. And white concrete has come in every building.
[24:57] It has had advantage that that can move forward quickly there. We're in a tourist season there that limits the execution time. And also the buying seasons are very regulated there on the coast.
[25:10] And yes, I stand by that. As architects, we try to be creative. And we also equipped a lower building with a white facade brick. And yes, we have to admit in that that that I mentioned there a moment ago that the
[25:25] quality on the paint is always harder to guarantee and yes I am sorry of yet to have to admit good that placing those those beautiful white facing bricks has not at all yielded freshest results and complaints from the owners with concrete as said in those
[25:42] prefabrication, the quality assurance is more obtainable. And, of course, it's a sales element. With that first tower, we used a lot of white concrete. And so the customer was in demand
[25:55] to get into the next two, three and the fourth phase that we're implementing today... I'm talking about a lead time of eight years now. So after eight years, we're down to the final phase of another 50,000 square feet of apartments.
[26:09] And so there's the developer's sales department asking later please include enough white facade elements in there that look that promotes that that fresh effectile as well
[26:21] the sales result completely clear to that is so also a very beautiful building when you arrive there if you drive in ostend towards the sea then not towards the center of Ostend, but really towards the beach.
[26:37] And then at one point you look to the left and you see all these beautiful buildings one after the other. Very, yes, really a, what do you call it?
[26:47] Landmark.
[26:48] A landmark, indeed. Thank you, Bernard.
[26:50] Worth visiting, then. Absolutely.
[26:53] All to the yards of CONIX RDBM.
[26:56] Let's do that.
[26:57] Thank you.
[26:58] Well, we talked about white concrete today. The benefits have been discussed, the arguments. So if tomorrow we can put up buildings in nice white, almost carbon-neutral concrete, then everyone will be...
[27:15] Is everyone winning.
[27:17] Good. Thanks for sharing that with us. Berna, you wanted to add something?
[27:21] Yes, not only us, but also future generations.
[27:25] Look, thank you guys for being there. And listeners, thank you for listening. Until next time. And stay curious. Concrete Steel Construction, the podcast, is a production of Lauer Media Group.
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AALBORG WHITE cement-based products have great undiscovered potential that offers opportunities to challenge the familiar and push the boundaries in terms of aesthetics. They are the building materials of the future. Plastically moldable properties, the true colors of the rainbow or the smooth white surface that allows the play of light [...]
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