Walk past any modern office tower and you will see a smooth wall of glass. Ask two people what it is called and you might hear “curtain wall” from one and “structural glazing” from the other. Both are right, and that is exactly why the terms get confused. The simplest way to understand curtain wall vs structural glazing is this: a curtain wall is the whole facade system, while structural glazing is one way of fixing the glass to that system.
This guide explains both, how they differ, and how to choose for your project.
What Is a Curtain Wall?
A curtain wall is a non-load-bearing outer wall, usually made of an aluminium frame filled with glass, metal panels or stone. It is called a “curtain” because it hangs off the building’s structure, attached at each floor slab, rather than holding up any of the building’s weight. Its job is to keep out wind and rain, let in daylight and give the building its look.
The frame is made of vertical members called mullions and horizontal members called transoms. Glass or panels sit inside the grid they form. Corinzo’s curtain wall and curtain wall system pages show this in practice.
Types of Curtain Wall
- Stick system: mullions and transoms are fixed to the building piece by piece on site, then glazed. It suits low and mid-rise buildings and smaller projects.
- Unitised system: large panels, already framed and glazed in a factory, are lifted into place and hooked together. It is faster on site and suits tall buildings.
- Semi-unitised system: a mix of the two, with some parts assembled in the factory and the rest on site.
What Is Structural Glazing?
Structural glazing is a method of attaching glass to the frame using high-strength structural silicone instead of visible metal caps or beads. The silicone bonds the glass to the aluminium frame behind it and carries wind loads, so from outside you see a continuous sheet of glass with only thin joints between panes.
There are different degrees of it:
- Two-sided structural glazing: two edges of each pane are bonded with silicone and the other two are held by visible caps. This gives strong vertical or horizontal lines.
- Four-sided structural glazing: all four edges are bonded, giving an almost frameless, all-glass look.
So How Do They Relate?
This is where the confusion clears up. Structural glazing is very often used within a curtain wall. A “structurally glazed curtain wall” is a curtain wall frame where the glass is bonded with silicone rather than held by external caps. A curtain wall can also be “capped”, with visible aluminium pressure plates and covers holding the glass on the outside.
So the real choice is usually not curtain wall or structural glazing, but which kind of curtain wall: capped, partly structurally glazed or fully structurally glazed.
Curtain Wall vs Structural Glazing at a Glance
| Point | Capped Curtain Wall | Structural Glazing |
| What it is | Full facade system with visible frame caps | Glass bonded to the frame with structural silicone |
| Look from outside | Visible aluminium grid lines | Smooth, near-continuous glass |
| How glass is held | Mechanical pressure plates and caps | Silicone adhesive bond |
| Design style | Strong framed rhythm | Sleek, minimal, monolithic |
| Workmanship needed | Standard facade installation | High; bonding is usually done under controlled conditions |
| Glass replacement | Simpler, remove caps | More involved, silicone must be cut and re-bonded |
Advantages of Each
Capped Curtain Wall
- Visible grid adds rhythm and character to a facade
- Glass is mechanically held, which many specifiers like for security
- Easier to replace a broken pane
- Suits a wide range of building types
Structural Glazing
- Clean, all-glass appearance that looks premium
- No external caps to collect dust or need painting
- Smooth surface sheds water well and is easy to clean with building maintenance units
- Popular for corporate offices, showrooms and hotels
How to Choose for Your Project
- Design intent. If the architect wants visible lines and depth, choose a capped or two-sided system. For a sleek glass box, choose four-sided structural glazing.
- Building height and wind load. Taller buildings face stronger wind. The system and silicone must be engineered for the site.
- Maintenance access. Consider how glass will be cleaned and, if needed, replaced.
- Heat and glare. Large glass facades need the right glass, such as reflective or insulated units. Thermally broken frames help too; see our guide to thermal break aluminium windows. External fins and aluminium louvers can also shade the glass.
- Installer experience. Structural glazing in particular depends on careful workmanship and quality control. Work with an experienced facade team.
Glass Choices for Curtain Walls
The frame holds the glass, but the glass decides how the building feels inside. Toughened or heat-strengthened glass is standard for safety. Laminated glass is often used where broken pieces must stay in place, such as above walkways. Insulated double-glazed units reduce heat and noise. Reflective and low-emissivity coatings cut solar heat gain and glare, which is important on large west-facing facades. Fritted or tinted glass can add privacy and shading while creating patterns on the facade. The right combination depends on orientation, height, use and the look the architect wants.
Common Misunderstandings
“Structural glazing holds up the building.” It does not. The word “structural” refers to the silicone carrying wind loads on the glass, not to supporting the building.
“Curtain walls are only for skyscrapers.” Stick-built curtain walls are common on low-rise offices, showrooms, hospitals and even large villas.
“All-glass means poor energy performance.” With the right glass and frame, a glazed facade can perform well. Glass choice matters as much as the system.
Final Word
A curtain wall is the complete glass and aluminium skin of a building; structural glazing is a way of fixing the glass so the frame almost disappears. Most projects choose a curtain wall and then decide how much of it to structurally glaze. To plan a facade for your building, explore Corinzo’s curtain wall systems or speak to our team.
Frequently Asked Questions (FAQs)
1. What is the difference between curtain wall and structural glazing?
A curtain wall is the whole non-load-bearing facade system. Structural glazing is a method of bonding glass to the frame with silicone, often used within a curtain wall.
2. Is structural glazing a type of curtain wall?
Structural glazing is a glazing method rather than a separate wall. When used in a curtain wall, it is called a structurally glazed curtain wall.
3. Does a curtain wall carry the building’s load?
No. It only carries its own weight and wind loads, and transfers them to the building structure.
4. Which looks better, capped or structural glazing?
Capped systems show a framed grid; structural glazing gives a smooth all-glass look. The choice depends on the design.
5. Is it harder to replace glass in structural glazing?
Yes, slightly. The silicone must be cut out and the new glass re-bonded, which needs skilled work.
6. Are curtain walls used in residential buildings?
Yes. They are used in premium apartments, villas and mixed-use buildings as well as offices.