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Sunhyewon: How SKM Architects Rebuilt a Seoul Mansion as Three Hanok

Otiima — Thu, 15 Oct 2026 10:38:55 +0000

A former family residence in Samcheong-dong becomes a house for art, research, and hospitality, with Otiima’s Correr Plus sliding system and guillotine windows in the envelope.

Samcheong-dong gets quieter the farther north you walk. Near the entrance, the neighborhood is crowded with visitors headed to Gyeongbokgung. Closer to Samcheong Park, the street narrows, the pace drops, and the slope of Bugaksan starts to set the terms. Here, on a raised plot behind a high wall, Sunhyewon sits.

The site has a long story. SK Group founder Chey Jong-gun bought the property in 1968 and lived there until his death. Afterward, it served for years as a corporate training center and guesthouse. It has now reopened as SK’s research institute and a cultural platform open to the public, and the interesting part is how it reopened: SKM Architects did not restore the house. They replaced it.

From Western-style mansion to three hanok

The original building was not a hanok at all. It was a Western-style mansion, a yangok typical of its period. For the new Sunhyewon, SKM Architects worked with Ongjieum Zipgongbang, the studio led by Professor Emeritus Kim Bong-ryeol of the Korea National University of Arts, to turn it into three timber halls arranged in a U-shaped courtyard.

Each hall has a distinct role:

Gyeongheunggak is the main building and the banquet hall. Its name refers to prosperity and is tied to Sunkyung, the company’s predecessor.
Harindang is the more intimate hall, closer to a traditional inner or reception house. Its name points to caring for one’s neighbors.
Dongyeoru is a raised pavilion used as a tea room. Its name suggests moving forward with society.

Together, the three form a single house rather than three separate buildings, and the plan makes that explicit. Reviewers have also noted that this approach is deliberate: instead of preserving the 1960s mansion as a period piece, the team built a new interpretation of hanok construction on the same ground.

Designed as a sequence

The architecture is best understood as a route. Visitors climb a short, turning stone stair from the street, pass a courtyard under the raised pavilion, then climb again. At the top, Gyeongheunggak appears framed at the end of the steps and reveals itself gradually until the lawn opens in front of it. Low to high, narrow to wide, shaded to bright: the proportions do the work, and almost nothing is ornamental.

That restraint matters for what comes next. A hanok is a timber post-and-beam structure with largely non-structural walls, so the envelope can be as open or as closed as the occasion requires. Sliding partitions have always been part of that logic. The architecture is operable by nature.

Where OTIIMA fits

OTIIMA Plus sliding system and guillotine windows were specified for the project, and both follow the same logic of operable surfaces.

Plus is a minimalist sliding system built around slim aluminum profiles. In a building with long timber spans and deep eaves, it stays visually quiet: large glazed panels slide aside, letting the hall meet the courtyard and disappear into the structure when open. Closed, they provide the thermal and acoustic separation that a historic-looking timber building in a dense city still needs.

Guillotine windows work vertically. Instead of swinging into the room or sliding sideways, the panel moves up and down, keeping the floor plan clear and leaving the opening height up to the user. In a raised pavilion with a view, that means the amount of air and landscape is adjustable, from fully closed to nearly fully open, with no hardware projecting into the space.

Together they let a contemporary envelope sit inside a traditional timber frame without competing with it. The frame stays the protagonist and the glazing stays the infrastructure.

An architecture that makes room for art

The first exhibition clarified the building’s character. From September 3 to October 19, 2025, the PODO Museum presented To Breathe — Sunhyewon by artist Kimsooja as the inaugural Sunhyewon Art Project 1.0. The central work covered the floor of Gyeongheunggak with mirrors, so visitors walked across reflections of the timber structure, light, and sky. It was the first time the To Breathe series had been installed in a hanok. Reservations for the show reportedly sold out within two days of opening.

A mirrored floor only works if the space around it is calm: precise proportions, controlled daylight, no visual noise at the edges. The building delivered exactly that.

What the project shows

Sunhyewon is a useful reference for anyone working with heritage typologies and contemporary performance. Three points stand out:

Rebuilding can be a legitimate form of continuity. The site’s meaning- a home that became a place of hospitality and learning, carried through even though the original building did not.
Operable envelopes are native to the hanok. Sliding and vertically moving glazing extend an existing idea rather than impose a new one.
Good glazing is measured by how little it announces. Slim profiles, smooth operation, and reliable sealing are what let the timber and the landscape stay in front.

Sunhyewon began as a private house, became a corporate guesthouse, and now operates as a shared cultural space. Architecture that can be reinterpreted this many times without losing its center is rare. The tools that open and close it quietly are part of why it works.

Solar Control Glass vs Low-E Glass: Understanding the Difference

Otiima — Thu, 08 Oct 2026 07:57:43 +0000

Glass significantly impacts a building’s thermal performance. For architects and specifiers, choosing the right glazing means balancing transparency and daylight with thermal comfort and energy efficiency.

Two commonly specified solutions are Solar Control Glass and Low-E Glass. While both use advanced coatings to improve glazing performance, they address different aspects of heat transfer.

Understanding the difference helps determine which solution or combination is best suited to each project.

Casa AL08 | Estudio Cano Arquiectura | © Tomeu Canyellas

What is Solar Control Glass?

Solar Control Glass is designed to control the amount of solar energy entering a building.

Its coating selectively filters solar radiation, reducing heat transmitted through the glass while allowing natural daylight in. This is especially important for large glazed façades or buildings exposed to direct sunlight.

The performance of solar control glazing is assessed by the solar factor (g-value) or solar heat gain coefficient (SHGC). A lower value means less solar energy enters the building.

By limiting unwanted solar heat gain, Solar Control Glass can help:

Reduce overheating during warmer periods
Lower cooling requirements
Improve thermal comfort
Maintain natural daylight while limiting excessive heat

It is especially relevant in warm climates, highly exposed façades, and projects with large glass areas.

What is Low-E Glass?

Low-E stands for low emissivity. Instead of mainly controlling solar radiation, a Low-E coating reduces heat transfer through the glazing.

The coating is an extremely thin metallic layer that reflects long-wave infrared radiation. In cold conditions, it helps retain heat inside the building instead of letting it escape through the glass.

The insulating performance of glazing is measured by its U-value. A lower U-value indicates better thermal insulation.

Low-E Glass can therefore help:

Reduce heat loss
Improve thermal insulation
Lower heating requirements
Maintain more consistent interior temperatures
Improve comfort near glazed surfaces

It is widely used in double and triple glazing and can adapt to various climatic and performance requirements.

Casa AL08 | Estudio Cano Arquiectura | © Tomeu Canyellas

Solar Control Glass vs Low-E Glass: What is the Difference?

The simplest distinction is: solar control glass controls heat from the sun. Low-E Glass controls heat moving through the glazing.

	Solar Control Glass	Low-E Glass
Main function	Controls solar heat gain	Reduces heat transfer
Main concern	Overheating	Heat loss
Key performance value	g-value / SHGC	U-value
Particularly useful for	Warm climates and solar-exposed façades	Cold climates and heating-dominated buildings

However, these properties are not necessarily exclusive.

Modern glazing solutions combine solar control and Low-E performance, letting the glass limit unwanted solar gains and improve thermal insulation.

Banánka House | Paulíny Hovorka Architekti | © Matej Haka

Which Solution is Right for a Project?

The answer depends on factors such as climate, orientation, glazing area, shading, building use, and heating and cooling needs.

Warm climates and high solar exposure

Solar control is often a priority where façades receive significant direct sunlight. Controlling solar gains helps reduce overheating and the energy needed for cooling.

Cold climates

Low-E performance is important where reducing heat loss is a priority. By improving thermal insulation, Low-E glazing helps retain internal heat and reduce heating demand.

Mixed climates

In climates with significant heating and cooling needs, glazing must balance both properties. A high-performance solution combining Low-E and solar control offers a more comprehensive approach.

Large glazed façades

The larger the glazed area, the more important the relationship between glass performance and the building envelope. Glass should be considered alongside the frame, orientation, shading strategy, and overall energy performance of the façade.

Banánka House | Paulíny Hovorka Architekti | © Matej Haka

Choosing Glass as Part of the Architectural Strategy

Solar Control and Low-E Glass are not just two alternatives. They address different thermal challenges and, depending on the project, can work together.

The right specification starts with understanding how the building interacts with its climate: how much solar radiation reaches the façade, how much heat it retains, and how the glazing contributes to the building’s energy strategy.

For architects and specifiers, the objective is to find the right balance between thermal performance, daylight, comfort, and transparency while preserving the architectural intent of the project.

The best glazing specification is therefore not necessarily the one with the highest performance in a single category, but the one that best responds to the building as a whole.

World Architecture Day 2026: Housing is a human right

Otiima — Mon, 05 Oct 2026 08:51:04 +0000

On October 5, the architecture world was asked to treat housing as a right and build accordingly. The theme serves as a policy statement and a design brief.

Every year, on the first Monday of October, architecture stops to ask what it is for. The International Union of Architects (UIA) created World Architecture Day in 1985 and holds it alongside the UN’s World Habitat Day. The 2026 answer is blunt. The UIA Council chose “Housing is a Human Right. Build It.” as the theme.

A theme with a verb

The second sentence of that theme is an instruction. The UIA asks architects to advance equitable access to housing through design, research, and advocacy, noting that safe, adequate, and affordable housing remains out of reach for millions, with direct consequences for health, dignity, and inclusion.

It also continues a line of thought. Last year’s theme was “Design for Strength”, which asked architects to strengthen the built environment’s ability to withstand, adapt, and be rebuilt. One year asked how buildings endure. The next asks who gets to be sheltered by them.

The size of the gap

The numbers explain the urgency. UN-Habitat now estimates nearly 3.4 billion people lack adequate housing, with close to 1.1 billion living in slums and informal settlements. At that scale, housing stops being a niche within architecture. It becomes the main question the discipline must answer.

What “adequate” means in design terms

“Adequate” can sound abstract, but the evidence behind it is specific. In 2018, the World Health Organization published its first guidelines on housing and health. They cover crowding, low and high indoor temperatures, injury hazards in the home, and accessibility for people with functional impairments. They also summarize existing WHO guidance on air quality and neighborhood noise. They are addressed to policy makers and professionals such as planners, architects, and developers.

Read as a designer, the recommendations turn into a checklist:

Space. Strategies to prevent and reduce household crowding earn a strong recommendation. In design terms, that means floor area and layout.
Temperature. Indoor temperatures should protect residents from cold, with 18 °C proposed as a safe level in temperate or colder climates. Insulation is recommended in new and existing housing. The same recommendations call for strategies against excess indoor heat. In design terms, that means envelope, orientation, and openings.
Safety. Housing should include devices such as smoke alarms and window guards, and it should reduce hazards that cause injuries. In design terms, that means stairs, edges and details.
Accessibility. A home that cannot be used by someone with a functional impairment is not adequate for them. In design terms, that means thresholds, widths and circulation.

The quiet work of the plan

None of this is spectacular and that is the point. Most of what makes a home adequate is decided early and almost invisibly: where a window sits, how rooms relate to each other, what the wall is made of, how a door opens. When it works, nobody thinks about it. When it fails, people feel it every day in cold bedrooms, overheated afternoons, and rooms too small for the family that lives in them.

That is why the UIA’s three verbs are important. Design is the plan itself. Research means learning how homes perform once people live in them. Advocacy means pressing briefs and regulations to require what the evidence supports. Architects hold only part of that chain, but it is where the decisions are first made.

From observance to practice

World Architecture Day usually celebrates what has been built. This year’s theme asks the profession to count what is missing. Housing is the oldest brief in architecture. It came before museums, towers and landmarks, and it is still the clearest test of whether the discipline serves the people it is meant for. A good house is a quiet achievement, and billions of people are still waiting for one.

OODA Launches New Book at Serralves: 15 Years of Portuguese Architecture

Otiima — Fri, 25 Sep 2026 08:21:43 +0000

On October 20 at 18:30, the Auditório do Museu at Fundação de Serralves will host the presentation of Some Kind of Romance, Any Kind of Existence, the new monograph on OODA published by Hatje Cantz. Otiima is proud to support this event, which brings together some of the most influential voices in contemporary Portuguese architecture to mark fifteen years of the Porto-founded studio’s practice.

The book resists the conventions of the architectural monograph. It is structured as a bifurcated narrative with two mirrored halves in dialogue. One half follows the studio’s engagement in Albania, where urban regeneration and identity reconstruction unfold amid rapid change. The other turns to Portugal, tracing how OODA treats time, heritage, and landscape as active materials in both rehabilitation and new construction. Together, the two sections speak less about buildings and more about a way of inhabiting the world, presenting architecture as chronicle.

At the center of the publication is a novel co-written by OODA and Ana Castanho, which moves through the studio’s projects without addressing architecture directly, letting the built work serve as backdrop to the narrative. Surrounding this central text are letters from nearly thirty architects and collaborators close to the studio, including Álvaro Siza, Eduardo Souto de Moura, João Luís Carrilho da Graça, Manuel Aires Mateus, Carme Pigem, Kengo Kuma, Jeanne Gang, and Benedetta Tagliabue. This is an unusual editorial choice: instead of critical essays contextualizing the work from outside, the book gathers testimony from peers who have watched it unfold within the discipline.

Following the presentation, a conversation will bring together four of the book’s contributing authors — Manuel Aires Mateus, João Luís Carrilho da Graça, Nuno Melo Sousa, and Eduardo Souto de Moura — alongside OODA itself. The discussion will have the same openness as the texts: an exchange about ways of seeing and making architecture, not a formal panel on completed projects.

Edited by OODA, with editorial direction by Diogo Brito and project coordination by Marina Rodrigues, the English edition of the volume runs 476 pages. It was designed by The Royal Studio and published by Hatje Cantz in June 2026.

OODA’s decision to frame fifteen years of built work through narrative and correspondence rather than drawings and data alone reflects a conviction we share: architecture is ultimately about how people inhabit space, and technical decisions only matter if they serve that experience. The same logic shapes how we think about our window and framing systems as infrastructure serving the life around them, not as objects to be noticed for their own sake.

Access to the event is free, subject to registration.

Choosing High-Performance Glazing for Luxury Residential Projects

Otiima — Thu, 17 Sep 2026 11:00:00 +0000

Glass has become one of the most technical materials in residential architecture. What once was a simple opening in a wall now regulates heat, filters sound, manages daylight, and carries structural loads across spans unthinkable a generation ago. For architects and homeowners building premium residences, choosing architectural glass is an early performance decision with consequences that last the life of the building.

Choosing well means understanding what each type of glass actually does and matching that function to the specific demands of the site, climate, and design intent.

Choose the Right Glass Early in the Design Process

In luxury residential projects, glazing is frequently the largest single surface on the building envelope. Floor-to-ceiling openings, sliding walls, and corner windows without visible framing place enormous performance demands on a single pane or, more accurately, on a carefully engineered glass assembly.

Getting the specification wrong is expensive to fix later. Getting it right early lets the glass stabilize indoor temperature, reduce HVAC loads, control noise from nearby roads or coastlines, and protect interiors from UV degradation, all without interrupting the view the design was built around.

Bow | Ana Costa | © Francisco Nogueira

The Core Categories of Architectural Glass

Float Glass

The base material for nearly every glazing application. Float glass is valued for its optical clarity and flatness but offers limited thermal or acoustic performance on its own. In residential settings, it serves as the starting point for more complex assemblies.

Tempered Glass

Heat-treated for strength, tempered glass breaks into small, blunt fragments. This is why building codes require it at floor level, near stairs, and in large panes. For sliding doors and expansive openings, a signature move in contemporary residential design, tempered glass is a baseline safety requirement, not an upgrade.

Laminated Glass

Two or more layers bonded with an interlayer (typically PVB), laminated glass holds together when broken instead of falling away. Beyond security, the interlayer also provides acoustic and UV performance, making laminated glass the standard choice for street-facing façades, waterfront homes exposed to wind noise, and any opening where sound insulation matters as much as the view.

Insulated Glass Units (IGUs)

Two or more panes separated by a sealed gas-filled cavity, IGUs are the backbone of high-performance envelopes. The cavity, usually filled with argon or krypton, dramatically reduces heat transfer compared to single glazing. Triple-glazed IGUs improve performance further but add weight and thickness that must be planned for in the frame and sliding-system design from the start.

Low-E (Low-Emissivity) Coatings

A microscopically thin metallic coating applied to one or more glass surfaces, Low-E glass reflects infrared heat while letting visible light through. Depending on the coating’s placement and formulation, it can be tuned to keep interior heat in during cold months or keep solar heat out during warm ones. This is a critical distinction for homes in climates with strong seasonal swings.

Bow | Ana Costa | © Francisco Nogueira

The Impact of Glass on Residential Performance

Thermal performance. Glazing is usually the weakest thermal link in a building envelope. IGUs with Low-E coatings and inert-gas fills reduce U-values substantially compared to single or standard double glazing, lowering heating and cooling costs over the home’s life.

Acoustic comfort. For residences near airports, arterial roads, or dense urban centers, laminated glass with an acoustic-grade interlayer often combined with asymmetric pane thicknesses within an IGU meaningfully reduces sound transmission without adding visible bulk to the frame.

Solar control. In sun-intensive climates, high-performance coatings manage solar heat gain without darkening the glass or distorting color, preserving the neutral high-clarity look that defines contemporary residential architecture.

Structural spans. Large-format sliding and pivoting systems require glass to carry structural weight. Laminated and tempered configurations engineered with the framing system determine how far a wall can open without intermediate supports interrupting the sightline.

Safety and code compliance. Tempered and laminated glass aren’t optional extras near floor level, on staircases, or in large panes — they’re the mechanisms that make expansive glazing legally and practically viable in a residential setting.

Integrating Glass and Window System Design

Glass should never be considered independently of the window system.

The performance of a glazed opening depends on the interaction of:

Glass + Frame + Hardware + Installation

A high-performance glass unit cannot compensate for an inadequate frame or poor installation.

This is especially important in minimalist residential architecture, where the goal is often to combine large glass areas with minimal visible framing.

As the frame becomes less visible, the performance demands on the entire system increase.

Miramar Tower | OODA | © Fernando Guerra

Frequently Asked Questions

What is the best architectural glass for a luxury home?

There is no universal solution. The best architectural glass depends on the home’s climate, orientation, size, solar exposure, acoustic needs, and performance targets.

What type of glass is best for floor-to-ceiling windows?

Floor-to-ceiling windows require glazing that meets the project’s thermal, solar, structural, and safety requirements. The glass must also be compatible with the supporting window system.

Is double or triple glazing better for residential projects?

Triple glazing provides higher thermal insulation but is heavier and thicker. High-performance double glazing offers excellent results in many residential applications. The right choice depends on the project’s specific requirements.

Does architectural glass improve energy efficiency?

Yes. High-performance glazing reduces heat transfer and controls solar gains, contributing to a more efficient building envelope. Its effectiveness depends on the complete window system and building design.

Can architectural glass improve acoustic comfort?

Yes. Certain glazing configurations, especially laminated and asymmetric glass combinations, improve acoustic insulation and reduce external noise.

Miramar Tower | OODA | © Fernando Guerra

The Role of Glass in High-Performance Residential Glazing

The most compelling residential architecture increasingly treats glass as invisible infrastructure: present everywhere, noticed nowhere. This effect works only when the specification is right. A frameless corner window or a wall-height sliding door looks effortless in a finished photograph, but behind it lies a deliberate stack of decisions: pane count, coating, interlayer, gas fill, and structural calculation, all tuned to the specific site and climate.

Residential glazing shapes how a home feels in every season: quiet, temperate, and open, without the comfort trade-offs that once came with large glass expanses. For architects specifying glass for luxury homes and the manufacturers and systems that support them, that combination—performance that disappears into the space experience—is where the real value of high-performance glass lies.

MEXTRÓPOLI 2026: Mexico City’s Architecture Festival Returns for Four Days

Otiima — Thu, 10 Sep 2026 15:35:07 +0000

From September 17–20, Mexico City will host the 13th edition of MEXTRÓPOLI – Festival de Arquitectura y Ciudad, bringing together architects, urbanists, designers, artists, institutions, and citizens to reflect on the city’s future through architecture.

OTIIMA is proud to support MEXTRÓPOLI 2026, joining a program that brings together some of the most relevant voices in contemporary architecture and creates opportunities to experience the city through lectures, exhibitions, discussions, architectural routes, and public space interventions.

MOVIMIENTOS: architecture in transformation

This year’s festival theme is MOVIMIENTOS.

MEXTRÓPOLI 2026 proposes viewing the urban environment not as fixed, but as a choreography of forces, trajectories, and frictions. The movement of people, ideas, spaces, and systems becomes a way of questioning established ways of designing and making cities.

The festival invites architects, urbanists, designers, artists, institutions, and citizens to challenge what appears permanent and explore other possibilities for the future of the city.

Over four days, more than 80,000 people are expected to take part in a program spanning Mexico City, turning its streets and cultural venues into spaces for discussion, observation, and experimentation.

The tree that floated away | Arquine Competition No.27 | MEXTRÓPOLI Pavilion 2025

A meeting point for international architecture

One highlight of MEXTRÓPOLI 2026 is its conference program, taking place at the Teatro de la Ciudad Esperanza Iris on September 18.

The program brings together an international group of architects, researchers, and architectural thinkers, including Riken Yamamoto, winner of the 2024 Pritzker Prize; Lina Ghotmeh, architect of the Serpentine Pavilion 2023; Junya Ishigami, winner of the Golden Lion at the 2010 Venice Architecture Biennale; LANZA Atelier, authors of the Serpentine Pavilion 2026; and Manuel Aires Mateus, co-founder of Aires Mateus and one of Portugal’s most recognized architects internationally.

The conference lineup also includes Anna Puigjaner, Roger Boltshauser, Beatriz Colomina & Mark Wigley, Josep Ferrando, Carlos Jiménez, Fernanda Lonardoni, and Joan Roig.

Together, these different practices and perspectives reflect the breadth of contemporary architectural thinking and the many ways architecture can engage with the city.

Beyond the conference room

MEXTRÓPOLI’s program extends well beyond its conferences.

The 2026 edition includes 12 conferences, three exhibitions, over 10 architectural routes and specialized visits, nine temporary public space installations, a light installation, film screenings, book presentations, and several dialogue sessions.

This multidisciplinary approach is central to the festival’s identity. Architecture is not shown only through buildings or drawings but through how people experience, inhabit, discuss, and transform their surroundings.

The architectural routes offer another way to engage with Mexico City. They take participants to places like Ciudad Universitaria, Reforma, Unidad Independencia, Tlatelolco, and Santa María la Ribera while exploring works by architects such as Teodoro González de León, O’Gorman, and Mathias Goeritz.

Architecture and the public space

Public space takes a particularly important role in this year’s edition.

Nine temporary installations will occupy Alameda Central in Mexico City’s Historic Center and Laguna, exploring relationships between architecture and public space and inviting visitors to interact with their surroundings.

Among them is el muro, the winning project of Concurso Arquine No. 28. Based on a permeable element, the pavilion creates a division that becomes an experience of connection and spatial transformation.

The intervention seeks to change how people experience the space in everyday life, illustrating the festival’s central idea that movement can catalyze transformation.

Three exhibitions, multiple perspectives

The festival’s exhibition program further expands the conversation around architecture and the city.

Entretejidas. Arquitectas mexicanas: presente, pasado y futuro, presented at Colegio San Ildefonso, recognizes the contributions of over 200 Mexican women architects in the discipline’s history.

At the Centro Cultural de España, Polis. Premio Europeo de Espacio Público brings together 32 projects organized around themes such as memory, recycling, mobility, markets, renaturalization, participation, housing, and care.

Meanwhile, Construir Europa. Arquitecturas Catalanas. EUmies Awards 1988–2026, presented at LAGUNA, showcases Catalan architecture recognized and nominated for the European Union Prize for Contemporary Architecture.

Together, these exhibitions broaden the festival’s perspective, connecting architecture with memory, mobility, public space, identity, and the evolution of cities.

A city to be explored

Perhaps one of the most distinctive aspects of MEXTRÓPOLI is that the festival isn’t confined to a single venue.

Its routes, installations, exhibitions, and public-space interventions encourage visitors to experience Mexico City as part of the program.

This approach reinforces the idea behind MOVIMIENTOS: the city is constantly changing, and architecture is one way to observe, question, and shape that change.

OTIIMA at MEXTRÓPOLI 2026

Events such as MEXTRÓPOLI create an opportunity to step back from individual projects and consider the wider questions shaping architecture today: how we move through spaces, how cities evolve, how boundaries can be reinterpreted, and how design can contribute to a better shared future.

From September 17 to 20, Mexico City will be a place to observe, explore, discuss, and transform architecture and the city.

OTIIMA will be there.

Structural Glass Façades: Performance, Materials, and Design

Otiima — Thu, 03 Sep 2026 08:30:53 +0000

Architectural glass has transformed how we imagine and experience buildings. Once used mainly to introduce daylight, windows and glazed façades have evolved into sophisticated elements that shape thermal comfort, acoustic performance, energy efficiency, safety, and the relationship between interior and exterior spaces.

In contemporary architecture, glass can become the opening itself, dissolving boundaries, framing landscapes, and allowing architecture to interact continuously with its surroundings.

As buildings focus more on performance, sustainability, and occupant comfort, the role of architectural glass expands. Understanding how glass has evolved, its types, and performance characteristics that influence specification is essential for architects, designers, and homeowners working with modern glazing.

This guide explores the evolution of architectural glass, its main types and applications, and the technologies shaping the future of modern building design.

CAM Gulbenkian Modern Art Center | Kengo Kuma Associates | ODDA | © Fernando Guerra

The Evolution of Glass in Architecture

Glass has been used in buildings for centuries, but its architectural potential changed dramatically with the development of industrial manufacturing.

Early architectural glass was small, irregular, and expensive to produce. Its primary function was to provide daylight and protect interiors from the elements. As manufacturing techniques improved, larger and clearer sheets became possible, allowing architects to rethink the relationship between solid walls and transparent openings.

The Industrial Revolution accelerated this transformation. Large-scale production of sheet glass enabled new architectural typologies, particularly in public buildings, commercial spaces, conservatories, and exhibition structures. Projects such as the Crystal Palace demonstrated the extraordinary possibilities of large expanses of glass with lightweight structural systems.

During the 20th century, advances in glass manufacturing and structural engineering expanded those possibilities even further. Modernist architecture embraced transparency to create lighter, more open environments. Floor-to-ceiling glazing, curtain walls, and increasingly minimal frames became defining elements of contemporary architecture.

Today, architectural glass can span large dimensions and delivers advanced thermal, acoustic, solar, and safety performance. Advances in framing systems also allow larger areas of glazing with minimal visual interruption.

The result is a shift from glass as a component of architecture to glass as an integral part of the architectural concept.

What is Architectural Glass?

Architectural glass is glass designed and processed for use in buildings. Unlike standard glass, architectural glazing can be engineered to meet specific performance requirements, environmental conditions, and aesthetic goals.

Its characteristics can be modified through various manufacturing and treatment processes, including heat treatment, lamination, coating, insulation, and combining multiple glass panes.

The specification of architectural glass depends on more than appearance. Factors like climate, orientation, building use, dimensions, acoustic needs, solar exposure, safety, and energy performance all influence the right solution.

This is particularly important in minimalist architecture, where large glazed surfaces can account for a significant portion of a building’s envelope.

VILLA SOORI | Laurence Barnathan & Cyril Montaudon | © WE ARE CONTENTS

Types of Architectural Glass

No single type of architectural glass suits every project. Different glass configurations offer various combinations of transparency, thermal performance, solar control, safety, and acoustic insulation.

Float Glass

Float glass is the basic form from which many architectural glazing solutions develop. It is made by floating molten glass over a bath of molten tin, producing a flat, highly uniform surface.

Standard float glass has limited safety and performance on its own but can be processed into more advanced glazing solutions.

Tempered Glass

Tempered, or toughened, glass is heat-treated to increase its mechanical strength and resistance to thermal stress.

A key advantage is its behavior when broken. Instead of large, sharp shards, tempered glass fragments into smaller pieces, reducing the risk of serious injury.

It is widely used in doors, façades, balustrades, large windows, and other applications that require increased safety and strength.

Laminated Glass

Laminated glass consists of two or more glass panes bonded together with an interlayer.

If the glass breaks, the interlayer holds the fragments together. This makes laminated glass valuable where safety, security, fall protection, or acoustic performance are important considerations.

Different interlayers can also provide additional functional properties, making laminated configurations highly adaptable to architectural applications.

Insulating Glass Units

Insulating glass units, commonly known as IGUs or double glazing, consist of two or more panes separated by a sealed cavity.

The cavity is usually filled with air or an inert gas like argon. This reduces heat transfer through the glazing and significantly improves the thermal performance of a window or façade.

Triple glazing adds another pane and cavity, providing further insulation where the climate and project requirements justify the additional thickness and weight.

Low-E Glass

Low-emissivity, or Low-E, glass has a microscopically thin coating that reduces thermal energy transfer through the glazing.

Depending on the coating and configuration, Low-E glass helps retain heat inside a building during cold periods and limits unwanted heat transfer during warm conditions.

It is an important component of high-performance glazing systems because it allows large glazed areas to combine transparency with improved energy performance.

Solar Control Glass

Solar control glass is designed to manage the amount of solar radiation entering a building.

It reduces solar heat gain while maintaining natural daylight and visual connection to the exterior. This makes it especially relevant for large glazed façades exposed to intense sunlight.

Solar control is achieved through various coatings, tints, and glass configurations. The appropriate solution depends on orientation, climate, building use, and desired daylight levels.

Decorative and Specialty Glass

Beyond performance, glass can also be modified for visual and privacy purposes. Frosted, patterned, textured, tinted, and digitally printed glass can introduce different levels of opacity, color, and visual character.

These solutions are often used where transparency must be balanced with privacy or where glass becomes part of the interior or façade design.

Arena Liga Portugal | OODA | © Pedro Cardigo

Energy Efficiency and Architectural Glass

One of the most important developments in modern glazing is the ability to combine expansive areas of glass with high levels of energy performance.

Historically, glass was one of the weaker elements of a building envelope thermally. Contemporary glazing technologies have changed this significantly.

The thermal performance of a glazed opening depends on the entire system, not just the glass. Glass configuration, coatings, cavity, gas fill, frame, seals, installation, and dimensions all contribute to the final result.

A high-performance glazing solution can help:

Reduce unwanted heat transfer
Improve indoor thermal stability
Reduce heating and cooling demand
Increase occupant comfort near glazed surfaces
Make larger glazed areas more viable in energy-conscious buildings

The orientation of the building is equally important. A glazing specification that performs well on a north-facing façade may not be appropriate for a heavily exposed south- or west-facing elevation.

For this reason, architectural glass should always be considered as part of the building envelope rather than as an isolated product.

Solar Control: Managing Light and Heat

Natural light is a fundamental reason architects use glass. Yet uncontrolled solar radiation can cause excessive heat gain, glare, and higher cooling needs.

Solar control is therefore about finding the right balance between daylight, views, and thermal comfort.

Glass coatings can selectively control the transmission of solar energy while preserving a high degree of visible light. External shading, orientation, glass specification, and façade design can also contribute to solar performance.

In contemporary architecture, this balance becomes particularly important as glazed areas become larger.

The goal is to control sunlight intelligently.

Well-designed glazing can allow daylight deep into interior spaces, frame views, and establish a strong connection with the landscape while limiting unwanted heat gain.

BOW | Ana Costa | © Francisco Nogueira

Acoustic Performance

As buildings become more open and connected to their surroundings, acoustic comfort grows more important.

Road traffic, aircraft, urban activity, construction, and nearby buildings can all affect interior acoustic quality.

The acoustic performance of glazing depends on several factors, including glass thickness, pane configuration, cavity width, laminated interlayers, and the overall window system.

Asymmetrical configurations, for example, can help address different sound frequencies, while acoustic laminated glass can further improve sound insulation.

However, glass is only part of the equation. Frames, seals, junctions, installation quality, and surrounding construction can all influence the acoustic performance of the entire opening.

For architects designing homes, hotels, offices, or buildings in dense urban environments, acoustic glazing can therefore be an important part of creating a genuinely comfortable interior.

Safety and Security

Large areas of glass require careful consideration of safety.

Tempered and laminated glass are widely used to improve safety in architectural applications. The appropriate configuration depends on location, dimensions, impact risk, height above ground, and building use.

Laminated glass can also contribute to security because the interlayer helps maintain the integrity of the glazing after breakage.

In large architectural openings, safety cannot be considered separately from the framing system. Glass thickness, panel dimensions, structural requirements, hardware, and frame design must work together as a complete system.

This integrated approach is especially relevant to minimalist architecture, where large panels and reduced framing create demanding technical requirements.

Glass and Minimalist Architecture

Few materials have influenced contemporary architectural aesthetics as profoundly as glass.

Its transparency enables architects to replace visual barriers with continuity. Walls become frames, rooms extend into terraces, and landscapes become part of the interior experience.

This effect is especially evident in minimalist residential architecture, where reducing visual elements is central to the design.

Minimalism demands more than reducing visible materials; the remaining elements must perform at a high level.

This is where advanced window systems become essential.

At OTIIMA, we approach the relationship between glass and frame as a complete architectural system. By minimizing the visible frame, our systems allow glazing to occupy a more prominent role in the architectural composition.

This approach creates a different relationship between architecture, light, and landscape.

Prapanca | PT ARTEMY+PAI-DESIGN

Architectural Glass and Indoor-Outdoor Living

Growing demand for seamless indoor-outdoor spaces has expanded the role of architectural glazing.

Large sliding openings, corner configurations, pocket doors, and minimal-frame systems create continuity between living areas and terraces, gardens, courtyards, and surrounding landscapes.

When closed, these openings provide protection and comfort. When open, they transform the building’s spatial experience.

This approach is particularly powerful in residential architecture, where the relationship between interior spaces and the surrounding landscape is often central to the design.

Glass becomes the element that enables this transition.

The Future of Architectural Glass

The next generation of architectural glass will be defined by a convergence of aesthetics, performance, technology, and sustainability.

One important direction is developing advanced coatings that control solar radiation, thermal transfer, and daylight with greater selectivity.

Dynamic glazing is another development area. Electrochromic and other switchable technologies change their optical properties in response to electrical signals or environmental conditions, allowing buildings to adapt glazing to changing sunlight levels.

Smart glass could reduce reliance on conventional shading systems while giving occupants greater control over their environment.

At the same time, advances in glass manufacturing are expected to support larger and more complex architectural panels. This will expand possibilities for frameless corners, expansive façades, and uninterrupted views.

Sustainability will remain another major driver. Future glazing solutions will need to consider operational energy performance, material efficiency, durability, recyclability, and manufacturing’s environmental impact.

The most interesting developments will likely occur where these different areas intersect: glass that performs better, adapts to its environment, uses fewer resources, and integrates more seamlessly into architectural design.

Designing with Glass: A Holistic Approach

The best architectural glass solution is not necessarily the one with the highest specification in every category because successful glazing begins with understanding the project as a whole.

Climate, orientation, building use, dimensions, solar exposure, acoustic environment, energy targets, aesthetics, ventilation, shading, and the relationship with the surrounding landscape must all be considered together.

This is especially important with large openings and minimalist façades. A visually minimal window must still provide structural stability, weather resistance, thermal performance, acoustic insulation, safety, and long-term durability.

Architecture may make the frame disappear visually, but the technology behind it remains fundamental.

Conclusion

Architectural glass has evolved from a simple source of daylight into one of the most sophisticated components of the contemporary building envelope.

From float and tempered glass to laminated, insulated, Low-E, solar control, and smart glazing, today’s technologies allow architects to create spaces that are brighter, more comfortable, more efficient, and more deeply connected to their surroundings.

Yet the future of architectural glass is now about creating better-performing buildings without compromising the architectural experience.

For contemporary architecture, the ultimate objective is to achieve transparency and performance simultaneously.

When glass, framing, technology, and architecture are considered as a single system, transparency become a way of designing how people experience light, space, landscape, and the building itself.

Smart Home Technology and the Future of Luxury Homes

Otiima — Thu, 27 Aug 2026 11:00:00 +0000

For most of its history, luxury in residential architecture meant marble floors, gold fixtures, and large homes that showed off status. Now, that idea is fading. Today’s homeowners and their architects are redefining luxury as something more subtle and genuine: a home that performs. Comfort that requires no visible mechanism, climate control that happens automatically, and views that remain uninterrupted by the technology managing them. This new approach to high-end home design is based on one idea: the best technology is the kind you never notice.

Smart Façades: The building as an active system

The façade has traditionally been treated as a line separating inside from outside, conditioned from unconditioned. In houses now designed at the top of the market, that boundary is becoming an active system. Sensors embedded in the envelope track solar gain, wind load, and interior air quality in real time. They feed data to systems that adjust shading, ventilation, and glazing performance without occupant intervention.

What distinguishes a smart façade from an automated one is responsiveness at the building-skin level rather than the room level. Instead of a homeowner adjusting blinds in a single room, the entire envelope recalibrates as a coordinated organism. It distributes thermal load across the structure like a well-designed circuit distributes current. For architects, this shifts the façade from a static aesthetic decision to an engineering discipline with its own performance metrics — solar heat gain coefficient, U-value, visible light transmittance — that now sit alongside proportion and material as design criteria from day one.

Dynamic Glazing: Solar control without sacrificing the view

Glass has always been the material of contradiction in residential design: the element clients want most and the one that historically compromised thermal performance most severely. Dynamic glazing — electrochromic and thermochromic systems that shift tint in response to light and temperature — resolves that contradiction without asking the client to choose between an unbroken view and a controlled interior.

The technical proposition is straightforward. Rather than layering curtains, blinds, or external brise-soleil onto a window system after the fact, dynamic glazing manages solar heat gain within the glazing unit itself, tinting incrementally as sun angle and intensity change through the day. The architectural proposition is more consequential: it allows floor-to-ceiling glazing — long the signature move of luxury residential design — to be specified without the acoustic and thermal penalties that once accompanied it. High-performance window systems built around triple glazing, thermal breaks, and precision airtightness already do much of this work passively; dynamic tinting adds an active layer on top, closing the gap between what a glass wall promises and what it delivers.

Net-zero as a design constraint

Net-zero performance has shifted from a certification checkbox to a design driver. In high-end residential projects today, energy performance is set at the concept stage—orientation, glazing ratio, envelope specification—rather than retrofitted through mechanical systems after the architecture is fixed. This sequencing matters because it changes what “luxury” architecture optimizes for.

A net-zero luxury home typically combines a high-performance envelope (glazing, insulation, airtightness) with on-site generation and storage, but the envelope does most of the work. A poorly specified window system forces oversized HVAC to compensate. A well-specified one with the correct thermal break geometry and glazing package for its climate reduces the mechanical load the building needs. Net-zero, in other words, depends more on glazing decisions than on solar panel count. This reframing positions the building envelope as infrastructure rather than finish, which is exactly the role OTIIMA’s window and framing systems are designed to fill.

Integrated Automation: Systems that disappear

The automation defining luxury homes today is notable less for what it does than for how little it shows while doing it. Lighting, climate, security, and shading systems are converging into a single operational layer, but the interface for that layer is disappearing into voice, ambient sensing, and scheduling logic that anticipates rather than waits to be commanded. The visible control panel, once a status symbol, now seems dated; the mark of a well-integrated home is the absence of visible controls.

This directly affects how glazing and façade systems are specified. Motorized shading, automated ventilation flaps, and sensor-linked tinting must be considered at the window-system level from the start. A framing system with the structural tolerance and cable routing to accommodate integration is increasingly a baseline requirement of premium specifications.

Biophilic Design: Nature as system

Biophilic design is often misread as a decorating strategy: greenery, natural materials, water features. In its rigorous form, it is a systems approach to how a building manages light, air, and the visual and physical connection to the exterior. Large-format glazing, operable façades, and indoor-outdoor thresholds are the architectural mechanisms through which biophilic principles get built.

This is where biophilic design and building performance converge. A sliding glass system that opens a living space fully to a garden or terrace is delivering a biophilic outcome — expanded domesticity, unmediated daylight, direct access to the exterior — provided its thermal and acoustic performance holds up when closed. The projects that succeed at this convergence, from residences on the Balearic coast to houses along Portugal’s own Atlantic edge, treat the glazing system as the hinge on which both experience and performance turn.

Invisible Architecture: The common thread

Across smart façades, dynamic glazing, net-zero performance, automation, and biophilic design, a single design philosophy recurs: the best-performing systems are the ones occupants stop noticing. A house that regulates its own temperature, tints its own glass, and manages its own air quality without visible apparatus reads paradoxically as more luxurious than one that displays its systems openly. Sophistication has relocated from what a home shows to what it no longer needs to show.

This is the terrain OTIIMA’s window and framing systems are built for. Minimalist aluminum profiles, engineered for structural performance, are the physical expression of invisible architecture. The technology of thermal breaks and precision glazing works silently so that a room offers its occupants simply the view, the light, and the air, with nothing standing between them and the landscape beyond. As luxury residential design continues its shift from ornament to infrastructure, that is the position worth building from.

Glass Sliding Doors for Seamless Indoor-Outdoor Living: Dunas Douradas

Otiima — Thu, 20 Aug 2026 11:00:03 +0000

Minimalist architecture features simple lines and large glass surfaces. However, achieving a seamless connection between interior and exterior spaces requires systems that become visually imperceptible while providing structural performance, thermal efficiency, weather resistance, and smooth operation.

The Dunas Douradas residence shows how these ideas work in practice. In Portugal’s Algarve region, the house fits into its natural surroundings due to thoughtful design choices, especially the use of glass as a key feature.

The architect’s vision

The concept behind Dunas Douradas aimed to blur the traditional boundaries between architecture and landscape. Each main living area was designed to maintain a constant visual and physical connection with the surrounding gardens, terraces, and natural light.

The architects envisioned continuous transparent surfaces that would frame the exterior and preserve the purity of the building’s minimalist design. The interior spaces had to convey openness, light, and connection with the surroundings throughout the day.

This approach required window frame systems that maximize transparency without bulky profiles disrupting the architectural composition.

Project challenges

Turning this vision into reality presented several technical challenges.

Large glass panels were essential for panoramic views, but larger sizes increase structural demands, panel weight, and operational complexity. The system had to support these panels while remaining easy to operate daily.

Furthermore, the transition between the interior and exterior had to be physically seamless. Visible thresholds, exposed tracks, or conventional frames would compromise accessibility and the delicate architectural details envisioned for the project.

Given the coastal location, the glazing system also had to withstand demanding environmental conditions, including intense solar exposure and wind loads, ensuring long-term durability without compromising thermal performance or weather resistance.

Balancing minimalist aesthetics with engineering performance became one of the project’s key requirements.

The solution: OTIIMA Fusion

To meet these requirements, the project incorporated the OTIIMA Fusion system.

Fusion was specifically developed for projects where architectural continuity is a priority. The system conceals the frame within the surrounding construction, allowing only the glass surface to be visible. Head, sill, and jambs are fully integrated into the architecture, reinforcing the impression that the glass simply emerges from the building itself.

Its flush threshold further strengthens the connection between indoor and outdoor spaces by eliminating visual interruptions and improving accessibility.

Beyond its minimalist appearance, Fusion provides the structural capability to accommodate large-format glazing along with the thermal insulation, airtightness, and weather resistance expected from a high-performance façade system.

For Dunas Douradas, this combination allowed the architectural vision to remain uncompromised while ensuring the house performs as effectively as it looks.

The result

This residence explains how a glazing system can transform the way it is experienced.

It allows natural light to penetrate deep into the interior, blurring the line between enclosed and open spaces. Panoramic views become part of daily life, and the nearly invisible window frame keeps the focus on the surrounding landscape instead of the window.

Large sliding windows create flexible environments where interior spaces extend naturally onto outdoor terraces, encouraging interaction with the weather and landscape throughout the year.

Despite the design’s openness, occupants enjoy excellent thermal comfort, protection from the elements, and reliable daily performance. It is a home with pure architecture and the technical capabilities needed for a contemporary luxury lifestyle.

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High-Performance Window Systems: Thermal & Acoustic Comfort

Otiima — Thu, 13 Aug 2026 11:00:00 +0000

Contemporary architecture is characterized by openness, transparency, and an aligned relationship between interior and exterior spaces. Large glazed surfaces, floor-to-ceiling windows, and minimalist window frames have become distinctive features of modern residential design.

Behind every minimalist window system are engineering, materials, and precision manufacturing that directly impact a building’s performance. They play a fundamental role in creating comfortable living environments by maintaining stable indoor temperatures, reducing noise, and improving energy efficiency.

Understanding the technologies behind these systems explains why high-quality windows are an investment in architectural quality and long-term performance.

Why window performance is important

Windows are among the most technically demanding elements of any building envelope. Besides providing natural light and unobstructed views, they must protect interiors from heat loss, solar gain, exterior noise, wind, and moisture.

Low-performance glazing systems can cause uncomfortable temperature fluctuations, condensation, high energy consumption, and unwanted noise transmission. High-performance systems contribute to healthier, quieter, and more energy-efficient homes while supporting the architectural vision of openness and transparency.

A window’s performance is never determined by a single component. It results from the interaction of various technologies working together.

Thermal Breaks: Reducing heat transfer

One of the most important innovations in modern window design is the thermal break.

Aluminum is valued for its structural strength, slim profiles, and durability, but it is also an excellent heat conductor. Without proper insulation, aluminum frames transfer heat between indoor and outdoor environments.

A thermal break interrupts heat flow by separating the inner and outer aluminum sections with a highly insulating material, typically advanced polyamide. This separation significantly reduces heat transfer and helps maintain stable indoor temperatures year-round. As a result, buildings need less energy for heating and cooling, occupants enjoy greater thermal comfort, and the risk of condensation on interior surfaces is greatly reduced. These advantages are especially important in luxury residences with large glass facades, where maximizing transparency must align with superior thermal performance.

Triple Glazing: More than an extra pane

Triple-pane windows are becoming progressively common in high-performance residential architecture, especially in projects that prioritize energy efficiency and occupant comfort.

Triple-pane windows consist of three glass panes separated by insulated cavities filled with inert gases, such as argon or krypton. These additional layers create multiple barriers against heat transfer, which significantly improves insulation while maintaining ample levels of natural light.

This window system reduces heat loss in winter, improves indoor temperature stability year-round, minimizes condensation, and lowers energy consumption. Triple-pane glass also offers improved acoustic performance, especially when combined with laminated glass. Its effectiveness increases with low-emissivity (Low-E) coatings, which reflect infrared heat while allowing natural light inside. This combination creates bright interiors that stay comfortable regardless of outdoor conditions.

Air Tightness: Preventing energy loss

Even the highest-quality glass cannot function effectively if unwanted air infiltration occurs around the frame.

Air tightness is a window system’s ability to prevent uncontrolled air leakage through seals, gaskets, and moving parts. Achieving exceptional airtightness requires precision engineering, careful manufacturing, and tight production tolerances.

Preventing outside air from entering keeps indoor temperatures more stable and heating and cooling systems more efficient. Airtight window systems also reduce drafts, limit moisture infiltration, improve indoor air quality, and enhance sound insulation by blocking airborne noise from small gaps in the building envelope.

Solar Control: Managing heat without losing daylight

Large glazed surfaces maximize natural light and reinforce the connection between the architecture and the landscape. However, they also increase solar exposure.

Without adequate solar control, interiors can overheat in warmer months, increasing cooling loads and reducing occupant comfort. Modern high-performance window systems address this through carefully selected glazing and specialized coatings that control solar radiation while ensuring transparency.

Solar control glass lets abundant natural light in while reflecting or filtering much of the solar heat. This helps maintain comfortable indoor temperatures, reduces reliance on air conditioning, protects interior finishes and furnishings from harmful ultraviolet radiation, and improves the building’s energy performance. Since every project has unique needs, the optimal glass specification depends on climate, building orientation, façade design, and the architect’s vision.

Acoustic Insulation: Creating quiet living spaces

Comfort is not determined solely by temperature.

As cities become denser and residential developments occupy urban spaces, acoustic performance has become a defining feature of luxury homes. High-performance window systems reduce exterior noise by combining laminated acoustic glass, multiple glass chambers, optimized glass thicknesses, precision sealing systems, and airtight frame construction.

Effective sound insulation results from the interaction of all window system components. This creates a quieter indoor environment that promotes concentration, relaxation, and well-being, even in busy urban areas or near roads, airports, or other sources of environmental noise.

Engineering every component as a complete system

The best-performing windows are not defined by a single specification alone.

Thermal breaks, advanced glazing, airtight construction, solar control, and sound insulation each contribute to overall performance, but their true effectiveness depends on how they work together. This systems-based approach lets architects design large-scale glazed facades that ensure energy efficiency, interior comfort, structural performance, and long-term durability.

As building performance standards evolve, high-performance window systems have become essential in contemporary residential architecture, helping projects achieve sustainability goals and provide exceptional living experiences.

Performance beyond visibility

The beauty of minimalist architecture often lies in what you can’t see.

While slim frames and panoramic views catch the eye, the technologies hidden within a high-performance window system ultimately define its value. These systems improve thermal stability, reduce energy consumption, minimize outside noise, and create consistently comfortable indoor environments, providing benefits felt in everyday life.

In premium architecture, true luxury lies in the invisible engineering that allows buildings to perform as beautifully as they look.