By adding oversized glass to our architectural portfolio, OBE is responding directly to the growing demand for larger, more transparent building designs, As architects continue to push design boundaries and redefine skylines, they value collaborating with a single, trusted partner like OBE to reliably deliver oversized glass solutions that combine performance with architectural impact.”
- Mark Adamson,
CEO of Oldcastle BuildingEnvelope

The Only Storefront Systems Featuring Thin Triple Glass for Superior Thermal Performance
DALLAS – (March 09, 2026)
Meeting evolving building codes for glass storefront thermal performance can be challenging, especially in regions like the Northeast and Northwest where higher standards and stretch codes demand superior solutions.
Oldcastle BuildingEnvelope eliminates much of the inherent complexity with its next-generation Series 6000 XT and Series 3000 XT storefront systems, engineered for IECC Climate Zones 3–8, including the Northeast and Northwest. They can be specified with either 1-inch insulating glass for enhanced energy efficiency or a 1-inch thin triple insulating glass unit for optimal thermal performance.
Storefront Systems with Thin Triple Insulating Glass
The Series 6000 XT and Series 3000 XT are the first and only storefront systems to offer a thin triple insulating glass unit. This design delivers up to 25 percent better thermal performance than traditional double-glazed storefront systems, without increasing system depth. The dual pour and debridge thermal break help maximize energy efficiency.
Designed to be compact, the Series 6000 XT is just 2-inches by 6-inches, and the Series 3000 XT features an ultra-low-profile, 2-inch by 4.5-inch design. These two storefront innovations also enhance condensation resistance, ensure long-term durability, and provide excellent comfort to occupants.

Key Features
- Infill options: 1/4 inch to 1-1/8 inch
- Accepts 1 inch insulating glass or a 1 inch thin triple insulating glass unit
- Outside glazing configuration
- Center set
- Screw spline assembly
- Thermally broken using a dual pour and debridge pocket
- High performance sill receptor requires no additional anchoring of sill member
- Accommodates zero sightline vents
- Tested to multiple standards
- Red List Free Option
When selecting storefront systems that are both flexible and capable of meeting the most stringent thermal performance requirements, the Series 6000 XT and Series 3000 XT set a new benchmark for thermal performance in storefront systems.
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