Product Spotlight: Milgard's New 4SG Spacer System, Now Standard on C700 Fiberglass Windows
Most people don't think much about the edge of a window's glass. But that thin strip between the panes, called the spacer, does a lot to keep a window sealed, efficient and comfortable for years. Milgard has upgraded it on their C700 Fiberglass Series windows, and it's a change worth knowing about.
What's New?
Milgard is now building C700 Fiberglass windows with a black thermoplastic spacer system called 4SG. It's standard on these styles:
Single-Hung
Casement
Awning
Horizontal Slider
Double Vent
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What Is a Spacer, and Why Does It Matter?
Dual-pane windows have two sheets of glass with a sealed space between them. The spacer runs around the edge to hold the panes apart and keep that space sealed. If the seal fails, you can get fogging between the panes and lose some of the window's energy efficiency.
Traditional spacer systems are built from several parts: a spacer bar, a primary seal and a desiccant to absorb moisture. 4SG replaces all three with one piece of warm-edge material.
The Benefits of 4SG
A seal built to last. 4SG bonds chemically to the glass and stays flexible. Glass expands in the heat and contracts in the cold, and 4SG moves with it instead of fighting it. That helps the seal hold up through years of temperature and pressure changes.
More comfort inside. 4SG uses warm-edge technology, which means it transfers less heat and cold through the edge of the glass. Outdoor temperatures have less effect on your indoor comfort, especially near the window.
Made for real-world conditions. Hot afternoons, cold nights, changes in altitude or pressure: the flexible edge is more forgiving under all of them. It's a good fit for the range of climates Milgard windows are installed in.
A cleaner look. The new spacer is black, so the edge of the glass looks sleek and low-profile.
Notes for Contractors and the Trade
Black foam spacer is still available to finish existing projects and for service needs, with a list price adder.
The Sales Order Number is now etched on a corner of the glass instead of printed on the spacer. Keep that in mind when you identify units for service or warranty.
Orders already in the system will be updated automatically to show the new spacer type and color.
The Bottom Line
The 4SG spacer is a small part that makes a real difference. It helps C700 Fiberglass windows hold their seal longer, stay more comfortable and keep performing season after season. If you're planning a replacement or new construction project, it's one more reason to consider Milgard's C700 Series.
Have questions or want a quote? Contact Lion Windows & Doors. We're happy to walk you through the options and help you find the right windows for your home or project.
