Why We Should Build With STONE (Again)

For thousands of years, we used one of the most abundant and beautiful materials to create marvels of architecture, many of which still stand to this day. That material is natural stone. It can be found all over the planet in huge quantities, and many cultures have used stone with great skill to build everything from homes to monuments and temples. However, after all those years, suddenly the material fell out of fashion. But why? I talked with an expert in London and even travelled to a huge quarry in Belgium to see if we can still build with stone in our modern age. And quite frankly, I was shocked about what they told me. In this video, you'll discover why this ancient material could be the solution to many of our modern problems. And we'll see if it's finally time to start building with stone again. I live in Amsterdam, a city built out of mostly brick and wood. But whoever looks closely will see that many plinths of buildings, steps and even the curbs are made from a bluish-gray kind of stone. And that stone comes from this quarry. This is Carrière du Hainon, where a local type of limestone is extracted, also known as Belgian bluestone. I'm here to discover more about this material and to see the extraction process in real life. John Vis is commercial director of the mine. Yeah, my name is John Vis. I'm commercial director of Carrière du Hainon, based in Belgium. So we are standing just on the edge of the quarry to see how the extraction of 200,000 cubes of volume a year come above. The Belgian bluestone is 100% limestone, what is used for more than 135 years in Belgium, Netherlands, Germany. So buildings, pavers for city centers, monuments, what else you can say, kitchen tops, everything what you can think is made from Belgian bluestone. And many buildings in which this stone has been used have stood for centuries. Of course, the use of stone goes back much further. The oldest intact structures built by humans we've found are made from, you guessed it, stone. Göbekli Tepe, a site with mysterious T-shaped pillars with intricate carvings of animals, rewrote our history books. The site is around 12,000 years old. Then there's ancient Egypt with its magnificent thousands-year-old pyramids and the ancient Greek temples still standing to this day. Stone has always been a popular material to build because it can be found basically anywhere. It is hard and durable and it can be pretty beautiful as well. When you see a stone building, there is a big chance it's made from one of the following seven types of stone. Granite, which is super hard and durable. Limestone, a bit less hard, easier to work and with an amazing texture. Marble, with its beautiful veining and glossy polish. Sandstone, composed of sand-sized particles with a rustic look. Slate, which is split into thin sheets and is often used for roofing. Basalt, which is dense, wear-resistant and amazing for cobblestones. And finally, travertine, a bit more porous, which you will find everywhere in Rome. The beauty of stone is that using stone from local quarries gives a city or town its character and identity. The use of stone has declined, however. In the 20th century, a construction industry was set up that revolves mostly around one material, reinforced concrete. In my video on that topic, you learn how destructive that has been. For example, it has spawned a sand mafia that disrupts fragile riverbank ecosystems by stealing the sand from them. Reinforced concrete causes extreme emissions and it doesn't even last long. That we started building with concrete had everything to do with a post-war economy, where building quickly and cheaply was seen as most important. But also with architects who loved concrete, as it gave them so much design freedom. And now that the slow-moving, risk-averse construction industry has been fully adapted to its use, there seems to be no way back. Or is there? People are realizing that it is smarter to move on to more durable materials that can be found locally. Building with timber is all the hype these days, and even ramped earth is making a comeback. But where is all the talk about that one material most of our earth's crust is made from? Who will spark a revival in construction with stone? But before we'll see the new champions of stone construction, I'd like to talk about something else. I'm finishing a new website that will have all my videos, interesting urban projects and much more all under one roof. For this purpose, I'm using Squarespace, the sponsor of today's video. Squarespace makes it super easy to create a completely personalized website using their new design intelligence system. A cutting-edge AI tool to empower anyone to create a beautiful or personalized website, tailored to their unique needs. Squarespace also offers an integrated payments tool, scheduling of client bookings, setting up email campaigns and it's all super easy to use. Check out squarespace.com for a free trial and when you're ready to launch, go to squarespace.com slash the aesthetic city to save 10% off your first purchase of a website or domain. I'm looking at a new building in London with Pierre Bidot, director at the stone masonry company. The building in front of us is built in a very unusual way. Instead of using concrete, they used massive stone slabs that serve as an exoskeleton. His company was involved in building it. So this is a 15-clack and well close and it is designed by Aminta and group works in 2017 and it's a completely functional fully load-bearing stone exoskeleton and so that means that the structure you see is load-bearing stone which itself is hooked to the concrete floor plates that span from the facade to the stairwell, the concrete stairwell. Pierre is a stone mason and knows the material extremely well. Perhaps a fun story is that I found Pierre's company while I was scrolling on twitter where I came upon some of their tweets about their products and stone in general. I had to talk to them. So when I traveled to Poundbury for filming, I first went by their office in London for an interview. So stone is something which is ubiquitous, you know, it's everywhere around us. We walk on it every day. It's a material that we have been working with in the last 20,000 years. So we've got a good knowledge on how to approach that material. So why should we use stone? First of all, stone is extremely durable. It proves also, of course, an extremely resilient material. It can go through the test of times with very little blemish. However, all that need, of course, to take into consideration that it's used in a certain thickness. You know, you cannot compare the strength of a 30 mil thick stone and 300 mil thick stone. When used for the structure of a building, it is mostly used in compression, like by using vaults and arches. Concrete, on the other hand, is often used under tension, using steel rebar inside the concrete to take those loads. But in many cases, rebar starts to deteriorate after 50 years, unless expensive measures are taken to protect it. Where concrete buildings and bridges with rebar will decay, stone buildings will simply just sit there until someone takes them apart. Using stone would change how we think about constructing buildings. For thousands of years, we built buildings where the walls were the main load-bearing structure, in masonry buildings that is. But with the introduction of reinforced concrete and steel, architects started designing buildings with a structural frame, onto which curtain walls were attached. This system is used all over the planet nowadays. But when we build with stone, the walls are the load-bearing structure once again. Stone is pre-cut in massive blocks, giving the building method its name Massive Pre-Cut Stone. This system has multiple advantages. The stones can be sawn to precise dimensions in the quarry or on site. Because the blocks are big, little sawing is required, saving costs. All the lifting and sawing can be done by machines, making it efficient. The blocks can be sawn in such a way that they become modules to build with, turning the building into a sort of Lego set. This makes construction even faster, more efficient and cheaper. Then there are the floor plates of buildings. These need to be made out of a material that works well under tension. Normally, reinforced concrete is used for this, but we already know that these don't last as long. Stone tends to break under tension. But there is still a way to use it for floor plates, by using post-tensioned stone, with a cable running through it, pressing stone blocks together. Another alternative is cross-laminated timber, or simply wooden or steel beams. The system that Vaulted AG is developing, a Swiss startup, would be another option, using flat concrete vaults, without rebar. Built the right way, such buildings could stand for hundreds of years or longer, and the stone blocks could eventually be reused for new buildings. This leads us to the second point. Stone is incredibly sustainable. Architecture is a violent activity. You need to cut, you need to dig, you need to extract, you need to crush, and so on. First of all, we should look at how many holes are we digging to get our material out of the ground. Of course, the very first one is that for stone, you just have more or less to dig only one. How many holes do you need to dig for concrete? You would have, of course, the aggregates. You've got the cement that you've got to produce from lime being crushed, so that's another hole. Usually, they are not the same aggregates. You need sand, but you need iron, because it's reinforced. You're already having quite a big impact just on the impact on the landscape. If we go back just for energy consumption, 50% of modern quarry used electrical power and purely electrical. There is another 50% who still use diesel engine to run that electrical system. There is still a bit of progress to be done. But it could all be electrical. It could be completely all electrical. The best part about natural stone is that it can be reused. Concrete can be reused as well, but with a lot of processing and intermediate steps. While natural stone buildings could be the quarries of the future. Any stone building is a quarry to be. The local amphitheater in south of France was going to be dismantled to build the part of a gothic church. The gothic church that was out of fashion was going to be reused to build a renaissance palazzo somewhere in Italy. I'm talking about solid stone, you know, big solid stone walls, material which by their thickness allow you to be reused again and again and again. An example is what this architecture firm is doing. Atelier Archiplan designed an apartment complex with massive stone blocks. These blocks have such a thermal mass that additional insulation isn't even necessary. But there's more. Stone can also be sawn into bricks. And these bricks are a low carbon alternative to traditional kiln-fired bricks. Finally, there's the element of beauty of course. Most stone, even the more rough and coarse types of stone, are just incredibly beautiful. Think of the Bath limestone. This honey-colored stone is a free stone, which means that it can be cut and squared up in any direction. The stone often has that natural pattern or texture that people crave and like, and it feels good to the touch. And we haven't even talked about all the opportunities of carving stone, by either craftsmen or even by machine, like Monumental Labs is doing in New York City. With ornament carved out of stone, buildings can display their beauty for millennia. So, with all these advantages of natural stone, I can hear you wondering, is there really no drawback at all? The first question is, is there enough stone? There is 15 miles deep crust of stone under our feet, all around the earth. So, we've got a bit of margin. Will we run out of stone? No, we will not run out of stone. And most importantly, we can reuse the stone that we have already here, because any stone building is a quarry to be. So, apparently there's plenty of it. The next question is, can it be used for toll structures? Well, yes. In France after World War II, they built this 16-story tower in Marseille, out of solid stone blocks. And in Algeria, the same French architect Fernand Pouillon built a 20-story totem tower. And making even taller towers should be possible. Just look at the Cologne Cathedral, which is built out of stone, reaches 157 meters. Of course, the question is if we really need to build this tall, but if we want to, it's possible. But I already know what the greatest argument against stone would be. It is simply too expensive. But is that really true? For the last 20 years, there's a huge amount of new architects who decided to look at the use of stone, which I call myself, you know, sort of unsexy stone, which, you know, cannot be used for cladding in rich areas from the city of London to a busy district in New York. And that can be used as a pure construction material. That means that those stones become extremely affordable suddenly, okay? Because nobody wanted them in the last 20 years. Most of the time, quarry output of materials sold is only 10%, even in some quarries, 3%. Okay, so you've got left over 90 to 95% of stone unused. That can go from a beautiful granite from the north of Europe, with just a line of white in the middle, will suddenly make it totally unusable. Sometimes we are in the market, we are checking how the price level is of natural stone. But if you compare it with a sintered material, sometimes even natural stone is cheaper to buy than the sintered materials. But the thing is that behind some brands of ceramics or composites, there are brands who are pushing a lot in marketing. Through that way, people are coming in contact with a kitchen company or a builder and they choose other materials. But sometimes people need to search and natural stone could be cheaper than the other products. So are we open to buy more local? And if we're all buying more local, then we can also drop the price a little bit. Because that helps us. If you have volume, then you can drop your price and everybody is happy. The most relevant question here is if building with stone is simply more expensive or too expensive. This all depends on how much we want to spend. Do we want buildings that last for thousands of years or buildings that we throw away every 50 years because they start to rot? Do we want buildings which we can disassemble to create new buildings or buildings that create streams of toxic waste that are hard to reuse? In France, they're literally building social housing with stone. They see the value of its good insulation and its quality and determine it's worth it. Perhaps to incentivize the construction industry to use stone, it could be subsidized. We are currently also subsidizing things like polluting fossil fuels or carbon neutral concrete. So why not a clean reusable building material? I believe the adoption of stone is not a technical problem. It is a choice we have to make. I envision a future in which our buildings can last for hundreds of years. The next step is to also make them beautiful with ornaments and moldings, ensuring that people will want to keep the I'm really excited about stone because it's just such a cool material. It's abundant, it's beautiful and it's made by our own planet. Of course, I'm a bit biased in this video, but still, by going with the status quo, we will never get more beautiful, livable and long-lasting cities and buildings. We need to explore the opportunities at the fringes. And in the end, I think many of us want a world that excites us, with beautiful buildings that are uplifting and that are truly long-lasting. Stone enables that, and that is why I believe we should build with stone again. Before you click away, have you ever wanted to know how the beautiful cities of the past were built and how we can apply that knowledge to build better cities today? Or are you fed up with how ugly and unlivable our cities are and you want to become a more effective advocate for change? I realize there are few places to learn this, so I'm creating one myself, a one-of-a-kind course that dives exactly into the topic of creating beautiful, livable places. Find more info in the description. A big thanks to my patrons, thank you for watching and see you in the next video!