Arquitetura Nacional Fits a Porto Alegre Law Firm into 100 Square Meters with Oak Walls That Open and Fold

Q: Who wrote "Arquitetura Nacional Fits a Porto Alegre Law Firm into 100 Square Meters with Oak Walls That Open and Fold"?

This article was written by UNI Editorial and published on uni.xyz, a platform for design professionals and creative thinkers.

Q: What is "Arquitetura Nacional Fits a Porto Alegre Law Firm into 100 Square Meters with Oak Walls That Open and Fold" about?

This article covers topics related to Office Building, Architecture, Interior Architecture, Porto Local Tiles, Building Planning & Design, Architectural Portfolio, Brazilian Architecture. In Porto Alegre, a real estate law firm downsizes by a third into a fit-out where oak joinery, copper services and sliding partitions do the work.

In Porto Alegre, a real estate law firm downsizes by a third into a fit-out where oak joinery, copper services and sliding partitions do the work.

5 min read·0 reads

UNI Editorial published Blog under Office Building, Architecture on Oct 10, 2026

Downsizing is rarely the brief architects ask for, but it is often the more honest test of design. When Escritório Piratini, a law firm specializing in real estate law, moved its headquarters into a 100 m² commercial unit in a new Porto Alegre building in 2017, it gave up roughly a third of the floor area it had before. Its previous office was about 50 percent larger. Arquitetura Nacional, with a team led by Lucas Pessatto alongside Eduardo L. Maurmann, Elen B. N. Maurmann and Paula Otto, was asked to make the smaller space work without making it feel smaller.

What interests us is where the design effort went. There is no grand gesture. Instead, the project puts its intelligence into three systems: a continuous oak joinery wall that absorbs storage, a set of movable white partitions that let rooms merge or separate, and a network of copper service pipes left fully exposed against a raw concrete ceiling. Marble supplies the ceremony at the entry. Everything else is calibrated so that a law office, a typology usually buried in paper, can carry its archive without being swallowed by it.

A Marble Threshold for a Legal Practice

Man pushing open a tall white pivot door in a marble-clad entry hall under copper conduits and a branching light fixture

Visitor walking through the opened white entry door with a firm nameplate, past a marble wall and tufted bench

Man standing before a marble partition in the entry hall, with a closed paneled white door and a tufted bench beside him

Entry vestibule with a veined marble reception counter, flush white door and copper ceiling pipes under soft cove lighting

Marble-clad reception corner with a tufted bench, branching copper chandelier and exposed copper pipes beneath a concrete beam

Reception desk with a mesh chair facing a copper branch chandelier, alongside a long oak panel wall in soft daylight

The entry hall is the one place where the project spends lavishly, and that is the right call. A veined marble wall and reception counter, a tufted bench and a tall white pivot door bearing the firm's nameplate give clients a reception sequence that reads as established and trustworthy. For a firm dealing in property transactions, that first impression is part of the service.

Note how compact this sequence actually is. The marble block does double duty as counter and partition, screening the working office from the threshold. A branching copper chandelier with bare filament bulbs hangs in front of the stone, the only decorative fixture in the scheme, and it borrows its language directly from the service pipes running overhead.

The Oak Wall as Storage Machine

Oak storage wall with pivoting doors swung open onto shelves, a blurred person walking past a marble counter

Oak cabinet wall with one tall door swung open and a man reaching inside, beside a marble counter edge

Pivoting oak veneer panels swung open to reveal shelving of books and boxes, beside a marble counter under exposed copper pipes

Corridor lined with oak cabinet doors and recessed pulls, ending beside a marble-clad block and a branching copper chandelier

Corridor of oak cabinet doors leading to a marble reception counter, with a copper chandelier and a glass door at right

Corridor of oak veneer cabinetry leading to a marble reception desk, with a person behind it and a branching copper chandelier overhead

The strongest move is the long oak-veneer wall lining the central corridor. Closed, it reads as a calm, continuous surface with recessed pulls and nothing to catch the eye. Open, its tall pivoting doors reveal shelves of books, binders and boxes. This is where the square meters lost in the move are recovered: storage that once needed its own room now lives in the depth of a wall.

The corridor framing also matters. Views down the oak run terminate at the marble reception block and the copper chandelier, so the circulation spine, often the dead zone in a small office, becomes the project's main visual axis. The joinery by Móveis Monte Castelo carries the whole idea, and it shows care in the alignment of door lines and pulls.

Copper Services on Display

Close-up of copper pipes on an orange steel bracket above an oak-veneer cabinet and exposed concrete ceiling

Close-up of a copper sprinkler pipe with a bracket and sprinkler head above an oak panel edge

Looking up at a diagonal copper pipe joined to a bracket under a concrete ceiling, with a tube light at right

Copper sprinkler pipe with a pendant head hanging below a concrete ceiling above oak cabinet tops and a glass strip

Copper sprinkler line running along a pale concrete ceiling above oak cabinets, with a glass gap between ceiling and joinery

Close-up of a copper pipe and bracket running above an oak shelf, with a light fixture beside the concrete ceiling

Rather than hiding the sprinkler lines behind a suspended ceiling, which would have cost precious height in a low commercial unit, the architects ran them in copper directly under the exposed concrete slab. Orange steel brackets hold them in place, and the pipes branch, turn diagonally and drop pendant heads with the precision of a drawn detail.

We think this works because it is consistent. The copper reappears in the light frames and the chandelier, so the services stop being an embarrassment and become the project's ornament. A thin glass strip between the top of the oak cabinetry and the ceiling lets the joinery read as furniture rather than a wall, and keeps the pipes visible along their full run.

Partitions That Rearrange the Plan

Man pushing a white sliding partition panel beside a meeting table, with copper pipes and tube lights along the concrete ceiling

Man opening a tall white folding partition beside a meeting table, with window light falling on a potted plant

Man in a white shirt standing by the window past a closed white sliding partition, copper pipes running overhead

Meeting room with two white tables, grey perforated chairs and copper-framed tube lights, daylight pouring through the window

Meeting table with pale grey task chairs beside a wall of oak shelving, under copper-framed linear light fixtures

Man in a white shirt working at a desk with two monitors beside a window overlooking distant buildings

The brief asked for spaces that could be divided according to the clients' needs, and the answer is a set of tall white sliding and folding panels. Pulled closed, they give the meeting room the acoustic and visual privacy a legal consultation requires. Pushed back, the meeting table joins the daylit perimeter and the office reads as one continuous floor.

This flexibility is worth more than a fixed extra room would have been. A small practice needs a conference space perhaps a few hours a day; the rest of the time that area serves as overflow work space with views across the city.

Working Rooms Built Around the Archive

Office workstations with white desks and mesh chairs under copper-framed tube lights, sunlight streaming across the floor through roller blinds

Office workroom with curved white desks, oak shelving of archive boxes and copper-framed light fixtures, daylight entering through the window

Workstation with curved white desk and mesh chair beside a glass partition, with filing cabinets under copper light fittings

Office corner with curved desk, filing cabinets and archive boxes on oak shelving beneath suspended copper light fixtures in daylight

Narrow office aisle with white filing cabinets, oak shelving and copper-framed tube lights hung below a concrete ceiling

Office corner with white drawer cabinets, archive boxes, a printer and a potted plant under copper pendant lights

The work areas follow a disciplined palette: curved white desks, mesh chairs, white filing cabinets and oak shelving stacked with archive boxes. Copper-framed linear lights hang below the concrete, and roller blinds temper the sun across the floor. The rooms are dense, but the repetition of a few materials keeps the density from turning into clutter.

A glass partition beside one workstation borrows light and depth from the neighboring space, a small but useful tactic in a unit where every opaque wall would shrink the perceived volume.

A Library Wall for Legal Books

Wall of white shelves filled with books behind a long desk and four grey chairs, copper-framed lights overhead

Meeting room with white shelves of books against an oak wall, under exposed copper pipes and tube lights

Oak wall panel with orange door lettering beside white folded-metal shelves holding worn legal books and hardcovers

Oak wall with white bookshelves holding rows of books, seen past a table edge under suspended copper tube lights

Corner of an office with white built-in cabinets, grey chairs and a framed photograph beneath copper-trimmed tube lights

Law firms still keep physical books, and here they are treated as a design element rather than hidden. White folded-metal shelves set into the oak walls hold worn legal volumes and hardcovers, giving the meeting areas the gravitas of a library without the mass of floor-standing bookcases.

Orange door lettering on the oak panels picks up the color of the pipe brackets, a small wayfinding touch that ties signage back into the service language of the ceiling.

The Kitchenette and the Return of Marble

Compact kitchenette with marble backsplash and sink beside a long oak-veneer wall, copper pipes running along the concrete ceiling

Kitchenette with a round marble table, framed photographs on a white wall and a marble splashback lit from below

Branching copper pipe chandelier with bare filament bulbs hanging in front of a veined marble slab wall

The compact pantry repeats the entry's marble as a backsplash, lit from below, with a round marble table set against framed photographs. Bringing the reception material into the staff kitchen is a democratic gesture: the best surface in the office is not reserved for clients alone. Copper pipes run past the oak wall here too, so even the most utilitarian corner stays within the same vocabulary.

Plans and Drawings

Floor plan drawing of an office with reception, meeting rooms, work areas, pantry and restrooms arranged along a central corridor

Two circular construction detail drawings of the joinery unit, showing a laminated glass panel, wiring voids and an LED strip recess

The floor plan clarifies the strategy: reception, meeting rooms, work areas, pantry and restrooms are threaded along a single central corridor, with the oak storage wall lining it. The circular construction details of the joinery unit are revealing. They show the laminated glass panel, wiring voids and an LED strip recess built into the cabinetry, confirming that the oak wall is also a service and lighting element, not just storage.

Why This Project Matters

Piratini Office is a useful case study for anyone designing small professional interiors. It shows that losing a third of your floor area does not require losing function, provided storage moves into walls, rooms are allowed to change shape and the ceiling is not sacrificed to hide services. The result is an office that feels generous at 100 m².

It also argues for restraint as an identity. Oak, marble, white and copper, deployed with consistency, give a law firm a recognizable character without branding gimmicks. The exposed copper sprinkler lines in particular show how a code requirement can become the thread that holds a design together.

Piratini Office by Arquitetura Nacional (lead architect Lucas Pessatto; team Eduardo L. Maurmann, Elen B. N. Maurmann, Paula Otto and Lucas Pessatto), Porto Alegre, Brazil. Area: 100 m². Completed: 2017. Photography: Marcelo Donadussi.

About the Studio

Arquitetura Nacional

Official website of Arquitetura Nacional, one of the studios behind this project.

arquiteturanacional.com.br

Share Your Own Work on uni.xyz

If projects like this are the kind of work you want to make, uni.xyz is a place to publish your own, find collaborators, and enter design competitions.