What curtainwall system is used for Class A office buildings in Florida?

ACG installs ESWindows ES8000T (thermal break) stick-built curtainwall and Euro-Wall pressure-cap curtainwall on Class A office projects. The ES8000T is a 4½" to 6" system with a polyamide thermal break, achieving U-0.28–0.36 with high-performance Low-E IGU. Euro-Wall pressure-cap offers a narrow sightline with deep thermal break depth. Both are available in HVHZ NOA configurations for South Florida.

What is structural silicone glazing (SSG) and when is it used on office towers?

Structural silicone glazing (SSG) replaces the exterior pressure cap with a silicone bond between glass and frame, producing a flush exterior with no visible aluminum cap. SSG is used on Class A office towers where the aesthetic specification calls for a glass-dominant facade without cap lines. SSG systems require factory-applied silicone (two-sided or four-sided) and field applied two-part silicone seal. ACG installs four-sided SSG systems on applicable projects.

What is AAMA 502 mockup testing for curtainwall?

An AAMA 502 mockup is a full-scale test assembly built before production installation. It verifies that the as-designed curtainwall system, installed by the same crew using the same methods, passes the specified performance tests: air infiltration (ASTM E283), water infiltration (ASTM E331), and often structural performance. On large office tower envelopes, the mockup is typically required by spec and is a condition of the GC/owner approval to proceed with production installation.

How does thermal performance affect Class A office glazing specification?

Class A office buildings often pursue LEED certification, which requires envelope performance per ASHRAE 90.1. Florida's energy code also imposes maximum U-factor and Solar Heat Gain Coefficient (SHGC) requirements. For ACG's typical Florida office work, this means specifying a thermal break curtainwall (U-0.28–0.36) with a high-performance Low-E IGU (SHGC 0.20–0.30). ESWindows ES8000T and Euro-Wall deep thermal break systems meet these targets.

How is a multi-story curtainwall envelope sequenced?

Multi-story stick-built curtainwall is installed floor-by-floor from the lowest floor up. ACG's typical sequence: anchor installation (floor-by-floor, coordinated with structural completion), vertical mullion installation (spliced at intermediate floors), horizontal installations, glass installation, sealant and pressure-cap installation. On high-rise projects, vertical sequencing is coordinated with the GC's floor-by-floor schedule and the elevator/hoisting plan for material delivery.

Does ACG perform AAMA 502 field water testing on office tower projects?

Yes. ACG performs AAMA 502 field water testing through a third-party testing agency. On office tower projects where the spec requires testing, ACG coordinates the test schedule, provides access panels for testing equipment, and is present during testing. Test documentation is included in the closeout package.

What is the difference between stick-built and unitized curtainwall for office towers?

Stick-built curtainwall is assembled piece-by-piece on the building face — vertical mullions, horizontal members, glass, and caps installed sequentially. Unitized curtainwall consists of pre-assembled factory-glazed panels that are lifted into place on the building. ACG installs stick-built systems primarily. Unitized is used on very high-rise or fast-track projects and requires a different installation process and crane coordination.

Office Tower Glazing — Class A Curtainwall & LEED Envelopes

FL CGC

#1531993

350+

Projects completed

1M+ SF

Glass installed

$3M / $6M

Bond capacity

Zero

OSHA recordables since 2021

3 offices

West Palm · Naples · Tampa

Why office tower glazing has different demands

The curtainwall on a Class A office building is the building's face. It drives the aesthetic, the tenant's experience of the space, the energy performance that shapes operating costs, and the envelope longevity that protects the investment over decades. Getting it wrong shows — in energy bills, in tenant comfort complaints, and in maintenance costs when water infiltration hits the interior.

Office towers also involve larger individual scopes. A 200,000 SF tower may have 40,000–60,000 SF of curtainwall glazing. The precision of the bid, the quality of the submittals, and the coordination on site all scale with the scope.

Curtainwall systems for Florida office towers

ESWindows ES8000T — thermal break stick-built

The ESWindows ES8000T is a 4½\"–6\" stick-built curtainwall system with a polyamide thermal break between the interior and exterior aluminum profiles. Thermal performance with standard 1\" dual-pane Low-E IGU: U-0.36. With high-performance triple Low-E IGU: U-0.28. The system holds a Miami-Dade NOA for HVHZ configurations. ACG installs the ES8000T on Class A office, hotel, and mixed-use projects throughout Florida where thermal performance and NOA compliance are both required. For more, see our ESWindows installer page.

Euro-Wall pressure-cap curtainwall

Euro-Wall's pressure-cap curtainwall system offers a deeper thermal break and narrower sightline compared to conventional thermally-broken systems. The pressure-equalized rain screen design provides superior water management for large envelope areas. ACG installs Euro-Wall systems on projects where the architect specifies a more refined exterior appearance with minimal cap dimension. For full Euro-Wall product information, see our Euro-Wall page.

Structural silicone glazing (SSG)

Four-sided SSG eliminates the exterior pressure cap, producing a flush glass face with silicone joints at the perimeter. The glass is bonded to the frame with structural silicone (factory-applied on two or four sides). SSG is the aesthetic specification for the most glass-dominant Class A facades. ACG installs two-sided and four-sided SSG on applicable projects. Key limitations: SSG requires strict quality control of the silicone application process; ACG follows manufacturer-specified quality procedures for all structural silicone work.

Curtainwall system comparison for office towers

System	Sightline	U-factor range	Aesthetic
Conventional curtainwall (no thermal break)	Standard	0.45–0.65	Visible cap lines
ESWindows ES8000T (thermal break)	Standard	0.28–0.36	Visible cap lines
Euro-Wall pressure-cap (thermal break)	Narrow	0.26–0.34	Narrow cap, refined
Two-sided SSG	Narrow horizontal	0.28–0.36	Flush vertical joints
Four-sided SSG	No cap visible	0.28–0.36	Full flush glass face

AAMA 502 mockup testing — what it means for office towers

On large office tower curtainwall scopes, the specification typically requires a full-scale AAMA 502 mockup before production installation begins. The mockup is a test panel built in a controlled environment (or on-site in a protected zone) that replicates the exact assembly — frame, glass, sealant, and anchorage — to be used in production.

Testing sequence on a typical office tower mockup:

Air infiltration test per ASTM E283 (at design pressure)
Water infiltration test per ASTM E331 or E547 (static and dynamic)
Structural performance test per ASTM E330 (at design pressure, inward and outward)
Thermal performance (sometimes) per ASTM C1363 or per simulation

ACG builds the mockup, coordinates the third-party testing agency, and is present for testing. If the mockup reveals a deficiency — typically a water infiltration path — ACG remediates and retests. Production installation does not begin until the mockup passes.

Multi-story envelope sequencing

Installing curtainwall on a multi-story office tower follows a specific floor-by-floor sequence. ACG's standard approach:

Phase 1 — Anchor installation

Slab edge anchors are installed as structural work completes each floor. ACG's anchor crew follows the structural schedule, typically one to two floors below the concrete work. Anchor layout is per the approved shop drawings and PE anchor calculations.

Phase 2 — Vertical mullion installation

Vertical mullions are installed from the lowest floor up, spliced at intermediate floors per the mullion splice detail. Vertical alignment is set with a plumb line or laser from the base. ACG installs verticals with thermal isolators at each anchor to comply with the thermal break requirement throughout the anchor condition.

Phase 3 — Horizontal installation

Horizontal members complete the grid. Horizontal clips, gaskets, and weep system components are installed. Each bay is verified for squareness before glass installation.

Phase 4 — Glass installation

Glass is staged per floor using the building's material hoist or crane. ACG's glazers set each lite from the interior or exterior depending on the floor height and access. Glass installation follows the approved glazing schedule — mark-by-mark verification ensures each lite's specification matches the opening requirements.

Thermal performance for LEED

LEED for Core and Shell (and LEED v4 Building Design and Construction) includes an Optimize Energy Performance credit that rewards envelope performance above the code minimum. For Florida office towers, meeting ASHRAE 90.1 baseline requires maximum U-factor of approximately 0.38–0.42 for the assembly, and SHGC must comply with the orientation-specific limit (typically 0.25–0.30 for south-facing Florida facades). High-performance Low-E IGU on a thermal-break curtainwall typically achieves these targets. ACG can coordinate with the energy modeler to confirm assembly performance against the ASHRAE 90.1 target before the spec is finalized.

Frequently asked questions

What curtainwall system is standard for Class A office in Florida?

ESWindows ES8000T (thermal break) and Euro-Wall pressure-cap are ACG's primary systems. Both achieve U-0.28–0.36 with high-performance Low-E IGU. Both have HVHZ NOA options for South Florida projects.

What is SSG and when is it used?

Structural silicone glazing uses a silicone bond in place of the pressure cap to create a flush glass exterior. Used on Class A facades where the spec calls for a glass-dominant aesthetic. Four-sided SSG provides the fullest flush appearance.

What is the AAMA 502 mockup?

A full-scale test assembly built before production installation to verify the curtainwall system meets specified air, water, and structural performance. Required by spec on most large office tower projects. ACG builds and tests mockups as part of the glazing scope.

How does multi-story curtainwall get sequenced?

Anchors installed floor-by-floor following structural completion. Verticals follow anchors. Horizontals complete the grid. Glass installed per floor from the bottom up. Each phase tracks one to two floors behind the preceding trade.

What thermal performance is needed for LEED?

Florida ASHRAE 90.1 compliance typically requires U-0.38–0.42 maximum for the assembly and SHGC 0.25–0.30 or lower depending on orientation. ESWindows ES8000T and Euro-Wall thermal break systems with high-performance Low-E IGU meet these targets.

Does ACG perform field water testing on office tower curtainwall?

Yes. ACG performs AAMA 502 field water testing through a third-party testing agency on all projects where the spec requires it. Test documentation is included in the project closeout package.

Send drawings to ACG

Office tower curtainwall requires precise execution at scale. ACG has the experience, the manufacturer relationships, and the PE-stamped engineering to deliver Class A curtainwall in Florida — HVHZ or otherwise. FL CGC #1531993. $3M/$6M bonding. 350+ projects.

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Office tower glazing — Class A curtainwall and LEED envelopes

The short answer