Southern Urbanism has partnered with Building Optimism and Building Culture to bring you the best stories from the people who build our cities. In this guest essay, Austin Tunnell explains how the study of ancient development informs his practice today.

Hi! It’s Austin. Welcome to The Building Culture Playbook.

Over the past decade I’ve built a vertically-integrated real estate development company from the ground up. I left my CPA career in 2012 for the Peace Corps in search of meaning and adventure. I stumbled into inspiration, which has since developed into a lifelong mission: building a thriving world for people.

This journey began with a two-year apprenticeship of hard labor laying brick for a master builder. Fast forward 9 years and Building Culture is an award-winning design + build company with exceptional emerging talent and a growing team. I’m now working on the last piece of the puzzle: syndicating and sponsoring our own developments—our first of which is a $33MM urban neighborhood slated to break ground late 2024.

Join me in real time as we pioneer a new way to approach development, fusing the liberal arts with construction and real estate to build a more beautiful, resilient, and thriving world for people. I’m glad to have you along for the ride! Cheers to building a richer life and a better world.

Segovia, Spain, and the nearly 2,000 year old Roman aqueduct that was still in use until the 1970’s.

Last summer I spent a couple weeks in Segovia, Spain, studying historic masonry structures with some of the top experts in the world. One of those professors I met, Philippe Block, a pioneering structural engineer and inventor, has shifted my perspective about concrete — one of the most widely used materials on planet earth — and how to think about it.

Years ago, I’d already moved away from the purist idea that everything should be “a traditional brick wall,” and shifted my language from saying “load bearing brick masonry” to “masonry-based construction systems” in terms of what we, at Building Culture, advocate for.

That is, using masonry, brick or stone, as the structure of a building as it has been used for thousands of years, and not just a siding held up by a wood or steel structure behind it, as is the case for the past 100 years.

Left: Solid triple wythe brick wall (load bearing brick masonry—the masonry IS the structure). Right: wood frame structure + single wythe brick veneer attached via metal ties.

I can promise you this: if the Roman aqueduct had been built with a wood or steel structure behind it, or even reinforced concrete with a stone veneer, it would have been destroyed within a few centuries of building it, probably less. Instead, they just stacked solid stones—that’s it—and it has persisted for 2,000 years.

But within that initial paradigm shift of me being open to various forms of structural masonry and not just “the traditional triple wythe brick wall”, I hadn’t fully come around to concrete, as so much of the concrete used today is destructive and used poorly.

We use what’s called “reinforced concrete”: loads of steel rebar encased in concrete. It’s extraordinarily strong — you can drive heavy vehicles across it. The problem? Concrete is porous and steel rusts. When steel rusts, it expands up to TEN times its original size — which destroys the concrete.

It’s a strong, but vulnerable system.

Degrading steel reinforced concrete. The concrete has broken away from the steel and will further accelerate rusting and self-destruction.

I say this often: failing infrastructure in America isn’t failing concrete, it’s failing steel.

Even though we now use epoxy coated rebar in big infrastructure projects, I’m still not big on embedding a ticking time bomb into our infrastructure that we could be building to last multiple centuries instead. We should be solving for long-term resilience over pure strength. But hey, it increases GDP when it crumbles and we have to rebuild ….

Also, remember that horrible condo building collapse in Florida in 2021? Failing rebar.

But concrete, like stone or brick, doesn’t have tensile strength – it works in compression. You can theoretically stack brick thousands of feet high before failing in compression (starts to crush itself under its own weight), but cantilever a single brick 4” from a wall, put weight on it, and the brick will break off easily. It wants to work with gravity.

So that’s exactly why people put steel in concrete! To add tensile strength and span large distances. You can’t embed rebar into stone or brick in the same way because it’s solid, but with concrete you can form it up, lay down grids of steel rebar, and pour the wet concrete in. This is what it looks like to rely on steel and tensile strength to span horizontal distances:

Using steel to span horizontal distances

You might be wondering: so if brick and stone work in compression, how can they span large horizontal distances? The arch! You don’t need any steel or tensile strength when you use the right geometry.

Using geometry to span horizontal distances

The humble arch has been around for millennia. And while I won’t get too technical here, the incredible thing about the arch is that it keeps everything in compression. Remember when I said you could stack brick thousands of feet high before failing in compression? Meaning a brick arch, entirely in compression, is incredibly strong. Or efficient is probably a better word.

Here is the single sentence Philippe Block uttered that fundamentally changed how I thought about concrete: Concrete is just artificial stone.

While I suspected this was how to think about it, I’ve never seen concrete used in this way in the context of traditional building systems. Modern engineers only use reinforced concrete, and traditionalists generally despise concrete altogether. Every expert I’ve met has been on one side or the other.

Until Philippe. But the moment he said this, it all clicked into place.

If concrete is really interchangeable with stone or brick, then it follows that the natural form of concrete to span openings is also the arch. There is no need for steel. You just need the right form.

The implications of this are shocking. Rather than 2 feet of this for a floor system:

Typical steel reinforced concrete floor system

You can just add a little curvature to it, get rid of 70% of the concrete and 90% of the steel (except for some external tie bars to resist thrust – depending on set up), and do this instead:

Philippe’s Rippmann floor system. Look how thin it is!

Why is this a big deal? Well, a lot of reasons that I’m interested in, but I’ll give you one of Philippe’s examples: floor systems in commercial buildings are a huge part of the material, labor, cost, weight, and carbon emissions of the entire building.

On a 25-story mid-rise, if you swap out conventional reinforced concrete floor systems with one of the unreinforced systems Philippe has pioneered, it saves 1200 concrete trucks and 20km of steel in the floor system alone. That’s before accounting for the reduced weight and implications on the piers and foundation. This is unbelievable.

Also, conventional concrete floor systems are extraordinarily heavy, and often kill people in earthquakes or fires. The twin towers collapsed straight down in a pancaking process as the floor system failed, up high, and began falling on each other in succession.

Would one of Phillipe’s floor systems have prevented a total collapse? I have no idea. But I’m pointing out that they are 80%+ lighter, and it certainly seems possible that a collapse of a few of those floor systems may not have led to a collapse of the whole building, as the lower floor systems could have supported the 80% lighter falling debris. Just a theory from a non-engineer.

Philippe also introduced me to Graphic Statics and the concept of strength through geometry – the ability to design hyper-efficient structures by only putting the material where you need it, enabled by understanding the flow of forces through a structure.

Remarkably, this isn’t new technology, though Phillipe is certainly innovating and building off of this millennia-old knowledge. Check out the King’s College fan vault (500+ years old) compared to Philippe’s floor system.

King’s College, UK

Versus this. See the resemblance?

Philippe’s Rippmann Floor System. See video here.

Pretty cool, right?

Or take the Pantheon, a 2,000 year old, unreinforced concrete dome that’s still standing.

There is a ton more to say, but here is how I’ve updated my thinking:

1. Unreinforced concrete is a viable, discrete masonry unit interchangeable with stone or brick—but can be formed into all kinds of unique shapes due to coming in liquid form and hardening through hydration. This opens up all kinds of possibilities, and has immediate implications at Building Culture.

2. The next evolution of “mass wall masonry” may very well be to reduce the mass for lighter and more efficient structures – which also happens to bring down costs, materials and carbon. Mastery of something is very often tied to increased efficiency – that is, doing away with everything that isn’t necessary. The fastest runners, for example, learn to limit any extra movement so that everything is in service of running faster. They only make movements that are necessary. The same can be applied to “mastery of masonry,” I think. This is a whole new world for us to explore at Building Culture, and I’m stoked.

In conclusion, below is a 2 minute episode trailer for my recent podcast with Philippe. It’s worth watching as you can see the floor systems in real life. Catch the full episode on your favorite podcasting platform here, or on YouTube here.

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Austin Tunnell is the Founder, CEO, and Head of Product at Building Culture, a holistic real estate development company dedicated to creating beautiful, resilient, and thriving places.

The keys to solving our housing crisis, climate challenges, and growing social isolation all lie in the way we design our cities. This summer, 24 students of all ages will journey from across the world, gathering in Charleston, SC to uncover the secrets of creating thriving urban spaces.

From July 7 through 19, these students will learn how to build resilient, beautiful, and prosperous places from industry leaders and academic specialists. While courses on net-zero construction and real estate investment abound, structured education on creating human-centered urbanism is strikingly absent. This gap is even more stark when looking at opportunities for students and young professionals. I know this far too well, as my own journey to understanding urbanism was not straightforward.

In 2008, on a mission to sharpen Spanish speaking skills, my high school class ventured across the Atlantic. After shuffling through airports, shuttling on buses, and scurrying to our hotels, we arrived at Toledo, the first stop of our language immersion trip. As the medieval gates of the city emerged in front of me, I could feel a subtle shift. I stepped through the towering gates of Toledo and basked in what I knew to be a sacred moment. This was my first true taste of historic urbanism - of how communities were once built - and I was witnessing something divine. With the zeal of a fresh convert, I frantically combed through narrow pedestrian corridors and lively plazas. Never in my life had I imagined that people could live in a place like this. Where were the cars? The strip malls? The front yards? I couldn’t make sense of it, but I knew my soul was soaring.

Just one week of wide-eyed journeys through a parade of urban spaces changed the course of my life. I may not have returned home fluent in Spanish (lo siento Señora Vasconcelos), but just six months later, I was applying to several undergraduate architecture programs to make the design of cities my profession. There was much to learn. I took classes in everything from the conventions of drafting plans to the science of how buildings stand up. Design studio became my second home, where I spent late nights in studio exploring ideas and making jokes with friends. For a few semesters, I was even able to trek across the globe through my program, studying the design of cities on three continents. I was doing everything I could to get a well-rounded education, but something was still not quite coming together. Regardless, I was on my path and I followed through, graduating with two degrees in architecture and one in real estate development.

It took many years for me to unravel the disconnect I felt in school. I now know that these programs taught how to craft artistic narratives and assemble the various parts of a building, but none were grounded in the values that make strong communities. In fact, I only had one class in six years of studies that even addressed the design of cities; it was taught as a history class, divorced from the way we build today. I must admit, I was lost when I graduated. Was I going to enjoy working as an architect? How could I make the kinds of spaces I experienced in Toledo if none of my schooling even mentioned urbanism?

To my surprise, the fog in my mind cleared quickly after graduating. After a desperate 6 months of job searching during the tail end of the last recession, I experienced the greatest bout of luck I have experienced: I stumbled into an internship with Lew Oliver. Within weeks of apprenticing alongside such an experienced urbanist, unconscious contradictions between my schooling and my experiences were exposed. The values of life and community that I held were being given real, tangible form. I began to devour everything I could about new urbanist theories, pedestrian cities, and how to design places we love. I travelled anywhere I could that exhibited great urban design. Very quickly, Lew began involving me in large and exciting projects, where I began relearning how to design and think about urban spaces. In everything from designing for small urban infill sites to laying out the masterplan of Trilith, Lew threw me into the fire. The passion that had slowly faded throughout my education had been reignited.

I now realize that this clarity came from seeing community values take physical form under the guidance of a master. Design is not simply a channel for creativity to be unleashed - it is an avenue to advocate for a better way of living. Community is not easily built or maintained in the isolation of the half-acre suburban lots choking Atlanta. Thriving is not a word you could use to describe sitting in traffic for hours on end each day. Inspiration is not easily found in the monotony of corporately developed 5-over-1 apartment buildings. There are much better ways of living, the design of our communities has significant impacts on our daily lives, and we can build a better world.

I was not alone in this journey – speak to any New Urbanist and they will have a similar winding path to clarity. The creation of Citymakers Collective and our inaugural Summer Studio is rooted in our team's desire to give others an easier path than we had. All of us involved have had similar experiences and want to provide a foundation for urbanist thinking to give the next generations a head start. We are curating resources and experts across all corners of urbanist professions to teach the principles of designing beautiful, resilient, and prosperous places – and in collaboration with INTBAU USA, we are creating programs to teach how to create better environments for people. Unlike most contemporary design programs, the Citymakers Summer Studio has been structured with our values at the base, blending theory, historic examples of loved spaces, and hands-on application. Participants will learn not just how to create spaces, but how to create lasting urbanism that fosters connection, resilience, and pride. By equipping the next generation of urbanists with the tools to design thriving communities, we’re not just shaping careers – we’re shaping the future of our cities.

Applications for the Citymakers Summer Studio will close on March 15. Don’t miss this opportunity to join a movement reshaping the future of our cities. Visit https://www.citymakerscollective.org/summer-2025 to apply or reach out to us at team@citymakerscollective.org to learn more.

To tell your freinds about Citymaker’s Collective, be sure to share this article.

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Will McCollum is a registered architect who has been working alongside celebrated urbanist Lew Oliver since 2015 to create meaningful and beautiful communities across the United States. He currently serves as Vice President for CNU Atlanta.

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Written By Austin Tunnell

We need to go back to the point where we were still building architecture that inspired, lifted the human spirit, and lasted millennia—and build upon those practices. Let’s apply building science with the same vigor, but to the time-tested building methods born from thousands of years of innovation, and then continue that tradition. We need to go back and explore mass-wall.

If you ask a child to draw a picture of a house, nine times out of ten they’ll draw a rectangle with a triangle on top. Why? Because it’s the most distilled representation of what we mean by a house. It’s symbolic, not just of a building, but of a concept—home.

That certainly varies by place and culture; not all houses should have gabled roofs. But good buildings—buildings that create harmony, comfort, and facilitate human thriving—do not have to be complicated. Some of the greatest cities, towns and neighborhoods are made up of 99 percent good buildings—simple, authentic structures arranged in a way that create spaces and provide a meaningful context for the 1 percent of great buildings. A mosaic of largely mundane pieces with a few jewels that all together create a masterpiece.

Traditional materials, with their inherent limitations, generally express themselves in very simple forms. It’s impossible to build the complex forms of a McMansion with traditional methods at a reasonable price. These constraints generally lead to better buildings. And with an average house size in the US of 2,500 square feet, we have some cushion for increased quality and smaller footprints.

While the masonry I do is beautiful for this century, I’m merely creating thoughtful, proportional buildings from authentic, durable materials. I am no master mason or craftsman, and certainly no brilliant designer. I am simply a builder: someone who facilitates the building of beautiful things, and wears whatever hats I need to wear to get it done.

In a hyper-specialized, increasingly complex world, professionals are often stuck in the silo of their specialty. Developers are stuck with spreadsheets and bank loans, architects with blueprints and building codes, general contractors with crews and construction. All of this generally pressures people to pursue giant projects, and giant projects rarely lead to good architecture. It’s too bureaucratic, like trying to paint a portrait by committee.

There will always be a place for big projects, but the fabric of good neighborhoods, towns, and cities is woven by small people doing small things. Small projects allow for a more flexible, organic development that keeps you engaged with the building as it unfolds over time. It’s like an author writing a novel. You set the characters in motion, but then they take on a life of their own. The characters begin to shape the story with you. You are not just imposing the story, but responding to it. Smaller building projects have fewer constituents and allow you to express your creativity and vision. To paint your portrait. To write your book. It’s the product of a human, not of an institution. Vernacular isn’t a style—it’s a process. 

In my experience, one person is entirely capable of developing, designing, and building at the scale of a six-home pocket neighborhood. I know an architect who just developed and built eight townhouses and a builder who is in the process of designing and building ten houses, plus a small duplex development. Everyone has their strengths, the things they love and are best at. And that’s good. But you can be good at design and still learn how to build a construction budget, run a pro forma, and learn how to talk to banks. On a small scale, none of this stuff is nearly as complicated as it seems.

The barrier to entry is extremely low. You don’t have to have a lot of money or experience to get your feet wet. You could buy a house as your “primary residence” with a conventional mortgage at 5 percent down and remodel the kitchen or bathroom. This would give you a chance to learn the permitting process, meet some subs, practice budgeting, and get some hands-on experience. If remodeling with cash isn’t an option, you could buy a house, or refinance one you own, with an FHA 203(k) loan that lets you wrap up the renovation costs into the mortgage. You can put as little as 3.5 percent of the total down to limit your out-of-pocket costs. For example, a $250,000 house plus remodel at 3.5 percent down is $8,750 cash out of pocket.

The FHA route is the most cumbersome, but also lets you get started with very, very little cash. If you buy a reasonably priced house in an even mildly appreciating area, it’s extremely low risk. If you get into a bind, you can either sell the house, rent or Airbnb it, and then move into a cheaper rental. You could also work through the FHA to buy and remodel up to a fourplex, or even to construct one from scratch. The only requirement is that you have to live in it for one year for it to qualify as your “primary residence.” If you rent the other units, you could then live for free, build equity, capture tax advantages, and benefit from appreciation.

After a year you could move out, rent that remaining unit, and qualify for another primary residence with a conventional mortgage. You would now have a cash-flowing fourplex in your portfolio that could be used as leverage to secure loans for larger projects. With the resultant access to capital, you’re on the road to becoming a developer, to controlling your own destiny—doing projects that you want to do in the way that you want to do them.

You don’t have to quit your well-paying job to make $12 an hour, as I did a little over five years ago. You can start with a small project on the side. You can work within your own limitations and set things in motion. In the process, you’ll meet suppliers and contractors, build relationships with banks, learn more about financing, and get to know city officials, inspectors, realtors, and other people in the business.   

Creating a new building culture doesn’t mean storming the barricades of the current institutions and power structures. It means taking action in our own spheres of influence to create compelling alternatives. To become builders. To remind people that humans don’t have to be destructive forces—they can cultivate and enrich. As we change the culture, policies and institutions will follow.

It’s not about a particular style or replicating some classical Order precisely, but about the continuation of the classical tradition, which ultimately is a value system. A system that values beauty, harmony, and stewardship, and celebrates the infinitely creative human spirit. Those values bridge across all places, cultures, and economic statuses yet express themselves uniquely in each, because humans are wonderfully diverse and enormously inventive. And when we take those values and express them in a durable architecture, we not only enrich the world we live in, but we also preserve and perpetuate those values, allowing posterity to build upon our accomplishments rather than having to overcome them.

No one else is going to do it. It will take you and me: small people doing small things.

Austin Tunnell is a Designer, Builder, Mason, Urbanist. After a brief stint as a CPA at KPMG and 2 years in the Peace Corps, Austin’s path into building began in the jungles of Panama where he was first introduced to the idea that how we build shapes how we live.  Captured by the idea, he went on to apprentice for a master mason and timber framer.  He plans to expand Building Culture to include apprenticeship programs, R&D, manufacturing, education and resale of traditional materials and methods—aiming to build a culture that expresses its ideals in a multi-century architecture: a whole new Building Culture.  @Build_Culture

This is an excerpt from a piece that was originally posted on Strong Towns on August 26, 2021. All photos provided by author.