The Portuguese language dictionary tells us that the word ecology comes from the Greek oikos (house, place where one lives) and logos (study), literally meaning “study of the house” or “study of the environment in which one lives.” In this studio, located in Porto, the concept is taken very seriously and becomes visually evident in every project.

In fact, sustainability and innovation are two concepts that have always been present at Hori-zonte since day one, more than ten years ago. “The studio bases its approach on the integration of nature in all projects, resulting in energy-efficient buildings that prioritize light, wind, sound, and water as protagonists.” Hori-zonte’s goal is to continue this path and, by 2030, to be able to always work on projects that are net zero.

But ambitions and dreams for the future do not end there. The strong respect for the local context of each client is reflected in the studio’s desire, led by João Castelo Branco, to contribute more to public space.

Masterplan Gaia
Gaia Hori-zonte
Do you remember the first time you realized you wanted to be an architect?

That’s an easy answer for me. My father is an architect. Since I was a child, I used to accompany him to the office. I can even say that I still keep the drafting table he used. I always saw him drawing, making models, designing. From a very young age, I would go there — first just drawing with colored pencils, later helping him with the models, even without fully understanding what I was doing. These are memories I’ve had since at least 2007.

And did your path end up following your father’s?

Yes, my father was always a self-employed architect. I graduated, with his help, and started working with him. I even spent some time abroad, mostly in Africa, at a time when the crisis was pushing us to look for opportunities elsewhere. But I came back, continued working with my father, specialized, did further training beyond my architecture degree, and together we developed the office. Over time, we realized that my father’s positioning in architecture was different from ours. A generational difference emerged, and he kindly stepped aside, handing the studio over to me.

Historic Palace Porto
Historic Palace Porto, Hori-zonte
Was that when you decided to expand the structure?

When I started taking over the studio, I realized my limitations as a designer. We know some things, but we never know everything. That was when I decided to expand the company into a partnership. I invited Diogo and Federico to join me. Later, André joined us. Diogo was my college colleague, and has been my friend for many years. He spent eight or nine years in Austria and also wanted something more local and connected to the philosophy we were implementing. The synergy was immediate. Federico began collaborating on occasional projects, and we quickly realized it made sense to integrate him. André came afterwards. He’s a force of nature, very sharp. When we created this group, each one bringing their own strengths, it became a stronger whole. That’s how Hori-zonte was born.

Sustainability is a very important point in your new work. Luxury or necessity?

It’s a necessity. First of all, we even want to demystify the word “sustainability.” It became a buzzword, but there is still a lack of knowledge about what it really means. It is necessary to improve living conditions in our apartments. By taking care of what is ours, we improve the whole, creating a symbiosis between nature and construction. In the 1980s and 1990s, there was mass construction, with many pathologies evident today — not in every building, but in many, due to the lack of basic care. Something as simple as cross ventilation is enough to solve many of these issues.

Historic Palace Porto
Historic Palace Porto, Hori-zonte
In practical terms, what does that mean for someone living in a building?

Air quality. Breathing better brings healthiness, fewer headaches, fewer respiratory problems. On the other hand, shading, for example, when well calculated, lowers the temperature in the summer and warms the house in the winter, thanks to more direct solar entry. This avoids thermal peaks and reduces the need for mechanical solutions like air conditioning which, in addition to being expensive, consume a lot of energy. Minimizing these efforts also means minimizing consumption. It creates a more comfortable environment, whether for living, working, or being.

There is a very distinctive identity in your projects.

Yes. At a very early stage of each project, we analyze the territory, carry out a bioclimatic study, understand where the winds come from, how the sun behaves in summer and in winter. We run simulations, and from this we define orientation, shading, ventilation. These studies, combined with municipal and national regulations, give us a very solid working base. That’s where the uniformity in the projects comes from. It’s not similarity by repetition, but continuity through the applied methodology.

What defines a luxury project?

More than money, luxury lies in the time to think. When there is time, solutions emerge with more quality, with more detail. Of course, there are materials that are recognized as luxurious, but a well-designed project can be inexpensive and still be a luxury solution, because it saves energy over time, lasts longer, and provides better quality of life.

Macau Valley
Macau Valley, Hori-zonte
Any recent project that you consider a good example?

We recently worked on a project with CLT (Cross Laminated Timber), with the goal of creating a net zero building. This requires investment, and not all developers are willing to make it. But we want our projects to be net zero by 2030. Another remarkable project was the residential building in Vila Nova de Gaia, on Rua de Macau, which we called “Macau Valley.” The street has a steep slope and the building was located on one side of the valley. The streets were not parallel, and the land was very steep. With a volumetric study, we managed to increase the building area by one thousand square meters (which pleased the client) and, at the same time, improve the quality of the building. We achieved our goals and exceeded the client’s expectations. It was a very rewarding project.

What would you still like to do in the future?

At Hori-zonte, we divide the work between public space and buildings. We do allotments, housing, small buildings, but we would like to do more public facilities. We have already participated in competitions, tried to apply our sustainable approach, came close in the results, but have not yet been selected. We would like to contribute with what we know for the good of the community. Working for the private sector is good, but we also have this desire to have a broader, more collective impact.