A window wall system fills the space between floor slabs. It's one of the most common glazing systems in Florida multifamily construction — but it's often confused with curtainwall. Here's the clear explanation.
The Core Difference
This is the one thing to remember:
- Window wall: Sits between the floor slabs. The frame is supported top and bottom by the concrete structure.
- Curtainwall: Hangs in front of the floor slabs. The frame is anchored to the face of the structure and spans multiple floors.
From the outside, both can look like a continuous glass facade. But the attachment method — and everything that flows from it — is fundamentally different.
How Window Wall Works
Window wall is installed slab-to-slab. Each floor has its own independent unit. The bottom of the frame rests on or clips to the top of the lower slab. The top of the frame is held by the underside of the upper slab.
This makes installation straightforward on repetitive floor plates. The installer works floor by floor. No continuous vertical members span multiple stories. Each floor is its own unit.
The slab edge is exposed on the outside of a window wall building. Designers handle this with spandrel glass, metal panel, or a slab cover integrated into the frame system.
How Curtainwall Works
Curtainwall hangs off the structure using custom anchors attached to the face of floor slabs or structural columns. The framing spans multiple floors — sometimes the full height of the building. The floor slabs are hidden behind spandrel glass.
Curtainwall is more structurally independent. It can accommodate larger spans, more complex geometry, and more variation between floors. It's also more expensive and requires more structural engineering. For a full technical breakdown, see our guide on what is a curtainwall system.
Side-by-Side Comparison
| Factor | Window Wall | Curtainwall |
|---|---|---|
| Attachment | Slab to slab (supported by floor edges) | Anchored to face of structure |
| Spans multiple floors? | No — one floor at a time | Yes — continuous vertical framing |
| Slab visibility | Slab edge visible (covered with spandrel) | Slab hidden behind facade |
| Cost (Florida) | By scope | By scope |
| Best building types | Multifamily, hotels, mid-rise office | High-rise office, commercial, mixed-use |
| Thermal bridging | More heat loss at slab edge | Better thermal control with proper design |
| Floor-to-floor variation | Hard to vary — works best with consistent heights | Can vary easily between floors |
| Speed of installation | Fast on repetitive floors | Slower (more custom anchoring) |
Where You See Window Wall in Florida
Window wall dominates Florida multifamily construction. Drive along any Florida coastline and look at the mid-rise and high-rise apartment and condo buildings. Most of what you see is window wall, not curtainwall.
Why? Because multifamily buildings have repetitive floor plates. Every floor is (mostly) the same height. Window wall installs floor by floor, which works perfectly with the construction sequence of a concrete frame building. Crews follow the structural pour up the building, glazing each floor as it becomes accessible.
You also see window wall on:
- Hotels: Guest room floors are identical — perfect for window wall.
- Mid-rise office: When floor heights are consistent and budgets are tight.
- Mixed-use buildings: Upper residential floors often use window wall even when the commercial base uses curtainwall or storefront.
ACG installed window wall systems on the Bradley Daytona project — a good example of a large-scale Florida multifamily application. See the Bradley Daytona project page for details.
When to Choose Window Wall Over Curtainwall
Choose window wall when:
- Your building is multifamily or hotel with consistent floor heights
- Budget matters — window wall is significantly less expensive
- Schedule matters — window wall installs faster on repetitive floors
- Floor-to-floor height is 9–11 feet (standard residential)
Choose curtainwall when:
- You need continuous vertical expression across multiple floors
- Floor heights vary
- The building is a high-rise commercial office or landmark project
- Thermal performance is critical (properly designed curtainwall has advantages)
For more on this decision, see our services page or explore our multifamily glazing contractor capabilities.
Window Wall Cost in Florida
Factors that push cost higher:
- Complex slab edge conditions
- Custom finishes or profiles
For large multifamily buildings with thousands of square feet of facade, that difference is significant.
Frequently Asked Questions
What is a window wall system in construction?
A window wall system is a type of glazing that spans from floor slab to floor slab — it sits between the structural floors rather than hanging in front of them. The frame is supported at the top and bottom by the concrete slabs. This is different from curtainwall, which uses anchors on the face of the structure and spans multiple floors continuously.
Where is window wall used most often?
Window wall is used most in multifamily residential buildings, hotels, and mixed-use projects where floors are repetitive. The slab-to-slab installation works perfectly when every floor is the same height and layout. Most mid-rise and high-rise apartment buildings in Florida use window wall — it's the dominant glazing system for that building type.