23 SUL Digs Down and Opens Up a São Paulo House Instead of Stacking a Second Story on Top

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This article covers topics related to Residential Building, Commercial Buildings, Building Design, Brazilian Architecture, São Paulo Architecture, Concrete House, Portuguese Architecture. In São Paulo, 23 SUL exposes timber trusses, strips old brick and excavates a meter into the ground to grow a one-story house without adding a floor.

In São Paulo, 23 SUL exposes timber trusses, strips old brick and excavates a meter into the ground to grow a one-story house without adding a floor.

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UNI Editorial published Blog under Residential Building, Commercial Buildings on Oct 31, 2026

Most renovation briefs that begin with "the house is too small" end with a second floor. The Caraçá Residence in São Paulo, by 23 SUL, refuses that reflex. The existing single-story brick house no longer fit its new residents, and the architects did need more room. They found it by going up inside the existing envelope and down into the ground, not by stacking a new volume on top. The result is a 233 m² home that keeps the proportions of the original building and feels far larger than it should.

The trick is not a single gesture but a set of small subtractions. The ceiling comes out, so the timber roof trusses become the ceiling. The stucco comes off, so the solid brick becomes the finish. Part of the site is excavated about a meter, taking advantage of the fact that the house already sat roughly 1.5 meters above the street. Bricks from demolished walls return as the perforated walls of a new outbuilding. We think this is the most interesting kind of addition: one built mostly by removing things and reusing what was already on site.

Removing the Ceiling to Find the Volume

Open living space under exposed timber trusses with a concrete kitchen island and a woman walking toward the sunlit courtyard

Long view down the timber-floored living area with a concrete island, bar stools and shelving beneath a skylit truss roof

Open living area under exposed timber trusses, with a pink daybed, leather chairs and shelving against a whitewashed brick wall, skylights admitting daylight

The defining move happens overhead. With the flat ceiling removed, the original wooden trusses sit exposed above a long, continuous living space, and skylights cut between them pull daylight down the full depth of the plan. What had been a dead attic now belongs to the room. The section grows without changing the roofline the street sees.

The architects divide the house by ceiling height: social spaces get the tall, truss-lined volume, and private rooms are kept lower and more enclosed. It is a simple hierarchy, and it reads immediately. You know where you are by how much air there is above your head.

A Kitchen That Doubles as the House's Spine

Kitchen island with wooden stools and a black steel hood beneath angled roof trusses and a skylight, glazed wall opening to garden greenery

Kitchen counter with concrete worktop, open shelves of glass jars, a green pendant lamp and a terracotta water filter by the window

Open shelving unit of ceramics and glassware below a library loft, with leather chairs in a patch of afternoon sun

Concrete shelving stacked with dishes beside a pink sofa and leather chairs, facing a whitewashed brick wall with small square windows

Whitewashed brick wall with small framed windows and artworks above a pink sofa, with a dog resting on the rug

The concrete island and black steel hood anchor the long room, set directly beneath the angled trusses. Open shelving does a lot of quiet work here. Instead of upper cabinets, glass jars, ceramics and dishes are stacked on concrete and timber shelves. These double as room dividers between cooking and lounging zones, so the kitchen never closes off from the rest of the space.

Against this, the whitewashed brick wall with its small square windows is the most restrained surface in the house. It keeps the original openings at their domestic scale, framing art and a pink sofa rather than competing for attention. The old house is still legible here, just painted lighter and given more room to breathe.

The Mango Tree Courtyard as the Real Living Room

Folding timber doors open from the kitchen to a brick-paved courtyard with a mango tree and perforated brick wall in backlight

Courtyard of terracotta paving around a large mango tree, with an open timber-framed kitchen on the right in afternoon sun

Dining table with bentwood chairs beneath a sloped timber ceiling, large glazing opening to a courtyard tree and dappled sunlight on the brick floor

Timber-framed window and open door looking onto a mango tree branches and a wooden deck scattered with fallen leaves

Gabled glass-fronted pavilion opened onto a terracotta-paved yard, its kitchen and dining area lit at dusk beneath a mango tree

If the trusses define the interior, the mango tree defines everything else. Folding timber doors pull back from the kitchen onto a courtyard paved in terracotta, and the dining table sits right at the glazing so the tree's canopy becomes the view from every meal. At dusk the gabled, glass-fronted volume reads almost like a lantern hung under the branches.

This is where the decision not to build up pays off most. A second story would have shaded the courtyard and loomed over the tree. Keeping the house low leaves the mango as the tallest thing on the lot, and the architecture arranges itself around it rather than the other way around.

Demolished Brick, Rebuilt as a Screen

Covered outdoor kitchen with a concrete and timber counter, pizza oven, grill and perforated brick wall beside a leafy tree

Side passage along the exposed brick wall with timber eaves, stepping stones in grass and a feathery bamboo in sunlight

Concrete stair rising past a planted bed of monstera and vines against an old brick wall, over a terracotta tile floor

Whitewashed brick stairwell with a small square window and a hanging mobile, terracotta steps catching a patch of sunlight

Stair landing with a white paneled door, board-formed concrete wall and a bookshelf above, sunlight falling across terracotta tiles

The project's material logic is circular. The two longitudinal walls of the original house stay, their stucco stripped to show solid brick. The walls that had to go were not hauled away. Their bricks were reused to build the hollow-block walls of the new outbuilding, including the perforated screen behind the outdoor kitchen with its pizza oven and grill. In backlight, that wall filters sun and air in a way that recalls the Brazilian cobogó, though here it is made from the house's own debris.

The stairs show the same mix of old and new at close range. Terracotta treads climb past old brick, board-formed concrete and a planted bed of monstera. Small square windows drop patches of sunlight onto the steps. None of it is precious. It is ordinary material handled with care, which is harder to do well than it looks.

Bedrooms Pressed into the Ground

Square dark steel window frame set in a brick wall, framing a bedroom with built-in white wardrobes and a blue bed

Bedroom with board-marked concrete ceiling and open sliding glass door to the garden, a blurred woman pushing a door beside a child's table

Living room with herringbone parquet floor and concrete ceiling, opening through glass doors to a terrace with potted plants and a tall tree trunk

Bedroom beneath a sloped timber ceiling with a ribbon window, white brick wall, wardrobes and a patterned throw over the bed

Bathroom under a sloped timber ceiling with a skylight, concrete bathtub, terracotta floor tiles and a potted plant in raking sun

Close-up of oak floorboards meeting terracotta floor tiles at a steel drain channel, with leaf shadows falling across both

The bedroom area is excavated by about a meter. Because the house already stood well above the street, this does not bury the rooms. It gives them the head height they need without lifting the roof. The private zone feels deliberately calmer than the social one: built-in wardrobes, board-marked concrete overhead in places, and doors sliding straight onto the garden.

Details carry the transitions. Oak boards meet terracotta tiles at a steel drain channel, a clean line between dry and wet floors. The bathroom keeps a sloped timber ceiling and skylight above a concrete tub, so even the most private room gets the raking light the rest of the house enjoys.

A Library Tucked Under the Roof

White bookshelves dividing a parquet-floored upper level, with a person seated on a bed by a window framing treetops

Upper-level reading nook with white bookshelves, a leather sling chair and a steel railing under a pitched timber ceiling with skylight

Freeing the roof space also makes room for a loft level of white bookshelves and reading corners above the living area, edged by a slim steel railing. Window seats look straight into the treetops. This is extra floor area won without adding a story. It lives inside the pitched volume the old ceiling used to hide, and it shows how much usable space sits unclaimed in many low houses.

Roof Deck, Night Light and a Modest Street Face

Timber roof deck with two folding canvas chairs, a small cedar cabin and a cat beneath a mango tree in afternoon sun

Covered brick ground-floor space with an open stair, a standing figure and a child's bike, string lights hanging in the tree at night

Street view at dusk of a low house behind a white wall and leafy plants, with the gabled glazed roof showing above

Outdoor space is layered vertically too: a timber deck with folding chairs and a small cedar cabin sits beneath the mango canopy, and a covered brick ground level holds the stair, a child's bike and string lights in the branches. From the street, though, the house stays almost anonymous: a low white wall, plants, and just the glazed gable peeking over. All the generosity is turned inward, toward the garden.

Plans and Drawings

Ground floor plan drawing showing living, kitchen and dining rooms, a carport and garden areas with tree canopies marked in green

First floor plan drawing showing an open living and dining area, a bedroom and bath wing, a staircase, and a side deck with a small pavilion

Section drawing cutting through a long flat-roofed volume with two hanging hoods, a lower level, a small pavilion and tree outlines beside it

The two plans show how the program spreads across the sloping lot. The lower level holds the carport and garden areas, with tree canopies drawn in green. The upper level holds the open living and dining zone, the bedroom and bath wing, the stair and the side deck with its small pavilion. The section is the most revealing drawing: it shows the long volume, the hanging kitchen hoods, the dropped lower level and the trees that the whole scheme was designed to leave standing.

Why This Project Matters

Cities like São Paulo are full of aging single-story brick houses that no longer suit the families who buy them, and the default answer is usually demolition or a heavy vertical addition. Caraçá Residence makes a convincing case for a third path. You can audit the section before adding mass. Ceilings can come down, attics can open up, and a raised site can be cut into. Much of the space a family needs may already be there, hidden above a plaster ceiling or under a meter of soil.

Just as important is the material ethic. Keeping the load-bearing walls and exposing the trusses saves embodied carbon, and so does turning demolition rubble into new walls. 23 SUL treats that as a design opportunity, not a compliance exercise, and the house is richer for it. It respects its original proportions and its mango tree, and it still feels unmistakably new.

Caraçá Residence by 23 SUL (lead architects Gabriel Manzi, Ivo Magaldi, Luís Pompeo, Luiz Florence, Moreno Zaidan and Tiago Oakley; coordination by Larissa Napoli), São Paulo, Brazil. Area: 233 m². Completed: 2023. Structural engineering: MR2 Engenharia. Landscape: Arboreto. Photography: Pedro Kok.

About the Studio

23 SUL

Official website of 23 SUL, one of the studios behind this project.

23sul.com.br

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