One-Wall House / Gabriela Casagrande arquitetura + Suna Arquitetura, Innovation
- Mark Lafond, RA
- Oct 1
- 7 min read
Sustainable Change Models of Innovation
The One-Wall House in Angra dos Reis, Brazil, is an innovative residential project distilled to a single organizing gesture: an 80-meter wall that runs the length of the site, aligning arrival, structure, services, circulation, and views into a coherent spatial narrative. On one side of this spinal wall, the house consolidates all technical functions—service zones, storage, and the working backbone of the home. On the other, life unfolds: pool, lounge, living spaces, and the landscape. The result is a residence that reads as both diagram and dwelling, a rigorous linear strategy that produces surprising spatial generosity. ArchDaily
Site, Program, and Concept
Set on a 2,800-square-meter canal-side lot in Angra dos Reis, the project reconciles coastal living with mountainous terrain and lush vegetation. The wall aligns the house to the canal while orienting openings to prevailing breezes and controlled views, bridging two distinct references the clients sought—countryside intimacy and beachside openness. A ground level holds the service and support program discretely behind the wall; above, a suspended bar contains the private suites. Between them, a double-height living volume opens fully to the exterior, allowing interior life to merge with the pool terrace and landscape. Floor-to-ceiling glazing pockets into the wall cavity, so thresholds disappear and the house can perform as an open pavilion when desired. ArchDaily
Spatial Organization and Circulation
The wall is not merely a separator; it is the wayfinding device and structural datum that calibrates gradients of privacy. Public spaces (living, dining, pool) are arrayed along the landscape side to maximize light and cross-ventilation, while the service spine keeps logistics—deliveries, laundry, storage, maintenance—out of sight yet directly accessible. Vertical circulation is folded into the thickness of the wall, maintaining the purity of the open plan. The suspended upper volume consolidates bedrooms into a single, legible bar, ensuring privacy without fragmenting the plan. The living void, positioned between ground-level service and upper-level privacy, becomes a climatic lung where air, views, and people circulate. ArchDaily
Structure and Materiality
Material choices are direct and tactile: exposed concrete, pressed bamboo, and Brazilian marble. These choices deliver a robust envelope capable of coastal performance while preserving a calm, textural interior palette. Prestressed concrete enables clear spans up to 12.5 meters and 6.5-meter cantilevers, freeing the plan from intermediary supports and allowing the façade glazing to retract fully. This structural clarity underwrites the project’s essential diagram: uninterrupted openness on the living side, concealed systems on the service side. The architects pair engineered systems with vernacular methods—ribbed formwork, native wood supports, and precise, low-tech solutions—so the house feels simultaneously contemporary and rooted. ArchDaily+1
Landscape, Water, and Accessibility
The pool is a functional landscape element as much as a recreational one. A helical ramp spirals into the water, creating a dignified, barrier-free entry that serves elderly users and anyone who prefers a gradual, step-less transition. This helix turns the pool into a small piece of inclusive infrastructure—one that aligns with universal design principles without visual compromise. Bathrooms feature retractable roofs to accelerate stack ventilation and allow full, sky-open experiences on temperate days. These devices, while simple, have outsized impact on comfort and energy moderation. ArchDaily
Environmental Performance and Passive Design
While the project’s published documentation does not enumerate mechanical systems, the architecture itself is composed for passive performance in a humid, maritime climate. The orientation along the canal and mountain exposures encourages breeze capture; full-height retractable glazing promotes purge ventilation; the suspended upper bar shades the ground plane; and the mass of concrete stabilizes diurnal temperature swings when properly cross-ventilated. Pressed bamboo adds warmth and acoustic dampening in key interior zones, working as a renewable finish with low embodied energy relative to many hardwoods. Retractable bathroom roofs operate like controllable clerestories, exhausting latent heat and humidity. These are simple, maintainable moves that reduce reliance on active cooling for much of the year. ArchDaily
Technologies and Smart-Building Features
Published sources focus on architecture and structure rather than MEP/BMS detail. In that light, the following technology profile is aligned with the home’s plan logic and typical high-end Brazilian residential practice; it is presented as a compatible specification rather than a claim of installed systems:
• Core network and controls. A distributed low-voltage backbone routed within the service side of the wall, with centralized network switching in a conditioned AV/IT closet. KNX, BACnet/IP, or equivalent open-protocol controllers would allow room-level scenes and whole-house logic without vendor lock-in. The wall’s continuous service cavity is ideal for zoned wiring and maintenance access.
• HVAC and micro-zoning. Variable-capacity heat-pump systems (VRF/VRV or high-SEER multi-split) with concealed ducted cassettes along the service spine, enabling zones for suites and living areas. ERV units placed along the wall can temper humidity during shoulder seasons, while operable façade sections maintain natural ventilation priority.
• Envelope automation. Motorized retractable glazing already implied by the design can be integrated with wind/rain sensors to protect interiors. Automated exterior shades at upper suites and perforated brise-soleil at the living bar would trim solar gains during peak hours.
• Lighting and scenes. Low-glare, dimmable LED downlights and linear grazers accentuate the ribbed concrete; exterior pathway lighting follows the wall datum. Daylight/occupancy sensors default to natural-light priority, with circadian scenes in suites.
• Water management. Smart irrigation zones tuned to microclimates along the canal edge and planting beds; leak detection valves on incoming lines and key wet rooms; variable-speed pool pumps and automated chemical dosing with protected access via the service side.
• Security and life safety. Perimeter cameras and discreet magnetic contacts integrated into glazing frames; addressable smoke/heat detectors and water-mist fire protection in the kitchen where code permits.
These systems align with the project’s split-brain organization—technology to the wall, living to the landscape—while preserving manual overrides and resilience in a coastal locale. Where the architecture already supplies passive performance (cross-ventilation, shading mass, retractable roofs), the smart layer should defer to the building’s form. ArchDaily
Project Data
The house was completed in 2024 with a total built area of 960 square meters on a 2,800-square-meter site. Lead architects were Pedro Sunyé and Gabriela Casagrande; interior design was led by Casagrande. Photography by Fábio Jr. Severo documents the planar clarity of the wall, the retractable glazing, and the bamboo-concrete-marble palette throughout. ArchDaily
Construction Cost Analysis (Methodology and Range)
Brazilian construction indices provide a transparent baseline for estimating costs even when a project’s actual budget is undisclosed. The official CUB/m² index published by Sinduscon-Rio for January 2024 lists high-standard (padrão alto) residential models in the State of Rio de Janeiro around R$3,292.62 per square meter, while clearly noting that CUB excludes foundations, specialty equipment, HVAC, pools, landscaping, designer fees, and other complements—items that are material to a high-end coastal home. Applying that base figure to 960 square meters yields a baseline of roughly R$3,160,915 for the building shell and standard inclusions only. sinduscon-rio.com.br
Market references further suggest that genuine high-end houses in Brazilian capitals commonly exceed the official baselines. Independent cost analyses place premium residential construction around USD$1,420.68 per square meter on average, with other Brazilian sources citing R$4,500–R$8,000 per square meter (and higher in top districts) given imported finishes, complex structures, and integrated technologies. For a 960-square-meter house, that implies an order-of-magnitude range on the completed project (exclusive of land): approximately USD$1.36 million using the international benchmark, or R$4.3–R$7.7 million using domestic high-end ranges before owner upgrades. The One-Wall House’s prestressing, long spans, Brazilian marble, custom bamboo work, helical pool ramp, and motorized glazing would tend to place it toward the upper end of typical Brazilian high-end residential costs. Estimation QS+2Recanto do Guerreiro+2
These figures are estimates based on published indices and market studies, provided to frame the project’s likely magnitude; they should be refined by a quantity surveyor using the issued-for-construction drawings, local contractor bids, and specific equipment schedules. sinduscon-rio.com.br
Other Innovations and User Experience
Two elements stand out for their subtlety and impact. First, the fully pocketing façade transforms the living bar into a breezeway pavilion, collapsing inside and outside without tracks or visible hardware dominating the view. Second, the retractable bathroom roofs bring daylight and sky directly into intimate spaces; coupled with natural materials, they create moments that are both sensorial and sustainable. Together with the wall—which doubles as structure, services, and wayfinding—the house demonstrates how a tight architectural diagram can unlock flexibility, comfort, and delight. ArchDaily
Construction Costs and Specifications
Project: One-Wall House
Location: Angra dos Reis, Rio de Janeiro, Brazil
Architects: Gabriela Casagrande arquitetura; Suna Arquitetura
Lead architects: Pedro Sunyé; Gabriela Casagrande
Category: House (single-family)
Completion: 2024
Site area: 2,800 m²
Built area: 960 m²
Primary organizing element: 80-meter continuous wall (structure + services + circulation datum)
Structural system: Prestressed reinforced concrete with long-span beams; cantilevers up to 6.5 m; clear spans up to 12.5 m
Envelope and finishes: Exposed concrete; pressed bamboo millwork/linings; Brazilian marble in key surfaces
Glazing: Full-height sliding/pocketing assemblies that retract into wall cavities to create uninterrupted openings
Accessibility: Helical pool ramp for barrier-free water entry
Passive strategies: Cross-ventilation via orientation and retractable façades; mass for thermal stability; retractable bathroom roofs for rapid exhaust
Landscape/water: Canal-side pool terrace integrated with living frontage; hardscape aligned to wall datum
Documented MEP/BMS: Not disclosed in published sources; house is compatible with open-protocol controls routed within wall service cavities
Baseline construction cost (CUB, RJ, Jan-2024): R$3,292.62/m²; 960 m² baseline ≈ R$3,160,915 (excludes foundations, pools, HVAC, landscaping, specialty equipment, designer fees, etc.)
High-end market references: USD$1,420.68/m² average for premium homes in Brazilian capitals; domestic guides cite R$4,500–R$8,000+/m² for alto padrão depending on finishes/technology
Order-of-magnitude project range (exclusive of land): USD$1.36 million (international benchmark) or R$4.3–R$7.7 million (domestic high-end ranges), subject to QS validation
Suggested smart-home stack (compatible specification): Open-protocol lighting/HVAC control, automated shades, ERV for humidity management, leak detection/irrigation zoning, pool automation, perimeter cameras, addressable life safety
Photographs: Fábio Jr. Severo
Credits: Architectural design by Pedro Sunyé; interiors by Gabriela Casagrande; project curation by ArchDaily
Items 1–15 and 21–22 are documented in the project’s published record; Items 16 and 20 reflect compatible specifications rather than confirmed installations; Items 17–19 derive from official indices and third-party cost benchmarks as cited.
References
ArchDaily. “One-Wall House / Gabriela Casagrande arquitetura + Suna Arquitetura.” 7 Sept. 2025. Accessed 11 Sept. 2025.
ArchDaily (Spanish edition). “Casa de una Pared / Gabriela Casagrande arquitetura + Suna Arquitetura.” 15 Aug. 2025. Accessed 11 Sept. 2025.
Sinduscon-Rio. “Custos Unitários Básicos de Construção (CUB/m²) – Janeiro/2024.” Issued 31 Jan. 2024. Accessed 11 Sept. 2025.
Estimation QS. “Building Costs Per Square Metre in Brazil – Turner and Townsend.” 7 Apr. 2025. Accessed 11 Sept. 2025.
Arquitecasa. “Índice Arquitecasa – Janeiro de 2025: Alto Padrão na Região Sudeste.” Jan. 2025. Accessed 11 Sept. 2025.
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