Mass timber has a logic of its own. Long before screws, before industrial adhesives, Japanese carpenters had already discovered that wood, when truly understood, can hold itself up.
That discovery has a name: kigumi. And centuries carved into every joint.
The technique involves shaping timber pieces with such precision that they interlock without any external fastening. What keeps the structure standing is the geometry of the joints — the intelligence of form. The Kintaikyō Bridge, built in 1673 in Iwakuni, is the most eloquent example: a timber arch spanning 36 meters with no intermediate columns, a feat rarely matched even in stone.
What makes this tradition singular is that its strength comes from the most seemingly vulnerable point: the joint itself. Where other construction traditions treat the connection between materials as the weak link, here it is the heart of the project. Stability is not imposed from outside. It emerges from the relationship between the parts.
A project built backwards
The Galeria Samanea began with a challenge from Idea!Zarvos to Architects Office: build a pavilion, not a sales suite, that would anticipate the experience of the Samanea development before the building existed. A timber portal on Rua Francisco Leitão, in Pinheiros, open to the neighborhood.
The initial design, developed by Architects Office under Greg Bousquet, called for a modular mass timber solution: repeatable glulam elements, controlled spacing, predictable construction logic. The conventional approach for timber structures — efficient, rationalized, replicable.
The conversation with Urbem opened a different path. The factory’s inventory held glulam pieces that could not be used structurally in other projects due to dimensional constraints: around 300 m² of engineered wood waiting for a purpose. The proposal that emerged, developed jointly by Urbem’s structural engineering team and Architects Office, was to redesign the project around that inventory.
As the Architects Office team described it: “The turning point was identifying timber as a space for reuse and extreme specificity. Our mass timber projects are usually based on absolute system rationalization. Here, the thinking went backwards: starting from an inventory, from a stock.”
The project changed in nature. From repeatable modules to a composition of unique pieces, each with its own dimensions, its own history from another site.
The structural puzzle
The first step was a detailed mapping of every piece in inventory: which could serve as columns, which as primary beams, which as secondary roof elements. The columns were the only element with a uniform cross-section across the structure, 19×19 cm. From there, everything else was variable.
Pieces were organized by weight and structural role: the most robust at the base, carrying the heaviest loads; the slenderest at the top, supporting the roof. Each beam is made of two pieces that wrap around a central column. From those, secondary beams run in the opposite direction, carrying purlins and rafters. A reciprocal structure: it only works when fully assembled, because each element depends on the others to find equilibrium.
The tension between the geometric rigor of the floor plan and the specificity of each piece produced situations that, in another context, would be problems: beams larger or smaller than intended, offset joints, sections of different depths meeting at the same point. The decision was to hide nothing. That variation became the visual identity of the pavilion. The marks of reuse were made visible as an aesthetic and tectonic quality, not a concession.
In the words of Urbem’s engineering team: “We had pieces of 19, pieces of 18, pieces with very different heights. The floor plan is very systematic, but the way the elements come together is entirely idiosyncratic. Each piece is unique and shares almost no dimension with any other.”
The logic of interlocking joints at industrial scale
For this logic of interlocking joints to work in mass timber, every connection was calculated digitally before any cut was made: load distribution, joint geometry, assembly sequence. Urbem’s CNC machining translated the parametric joints into physical pieces ready to fit together on site. The principle is the same one that guided Japanese carpenters. The tools are those of the 21st century.
The presence of metal is honest and minimal. Metal connections appear only at column bases, raised 5 cm off the ground to prevent water infiltration. Bolts appear at select points to close structural frames where the reciprocal system needed anchoring. Everything else works through the logic of interlocking joints: one piece holding the next.
The roof follows the same honesty: two inverted pitches at 5% slope, channeling rainwater into a central gutter for reuse, with sandwich panel over OSB for thermal comfort. Each slope responds to the structural logic of the available pieces, without forcing a uniformity the material does not have.
A structure that does not end
Galeria Samanea was built around a question rarely asked of a sales pavilion: what happens to this building when it’s done?
The joints that hold the structure together are the same ones that will one day allow it to be dismantled. What was assembled can be reassembled elsewhere, in a different configuration, for a different use. The glulam pieces that arrived as surplus inventory gain new life here, and the timber-to-timber connections ensure that life can continue beyond the pavilion.
Set as a gateway and public plaza for the complex, which includes Café Sagui by chef Cesar Costa, Cine Samanea and the Samanea Dome, the Galeria condenses the built footprint to free up the ground: more green space, more permeability, more collective space. The exposed timber and the biophilic landscaping by Rodrigo Oliveira establish the same atmosphere the permanent development will bring to the address.
What remains
There is a thread connecting the Kamakura-period carpenter to the CNC router that machined the beams of Galeria Samanea. It is not a straight line. It crossed centuries and oceans. But the thread is there: the intention to build with timber as protagonist, reduce the accessory to a minimum, and trust that a well-designed joint is worth more than an extra fastener.
As Urbem’s engineering team put it: “After six years working with structures, this project showed me that it’s not the forces acting on the pieces that matter most, but the way they interlock, the way they distribute through the composition.”
At Galeria Samanea, 300 m² of glulam that had no function gained function, identity and place. A pavilion that is, at once, structure, language and position: a statement that building well means thinking about what comes before the project and what remains after it.
If you are developing a mass timber project and want to understand how timber-to-timber connections and glulam systems can contribute to your build, Urbem’s team is ready for that conversation.
