Soundproof Secondary Windows

A: A secondary soundproof window is a separate interior sash installed inside your room, a few inches in front of the existing window. Rather than replacing your primary glazing, it creates a sealed, decoupled air cavity that interrupts sound transmission. Three physical principles drive the performance: mass (acoustic laminated glass resists vibration), damping/decoupling (the air gap breaks the vibration path), and airtightness (continuous compression gaskets stop high-frequency leaks). The result is a dramatic reduction in traffic, rail, aircraft, and street-level noise without touching the exterior façade. Because the unit mounts to interior framing, it’s ideal for high-rises, condos, leased spaces, and historic buildings where window replacement is restricted. Our systems are custom-fabricated to the millimeter, ensuring a snug fit around out-of-square openings and masonry returns. Choose fixed, hinged, slider, or lift-out panels based on your access and cleaning needs. In day-to-day use, you simply engage the latch, the seals compress, and the room becomes notably quieter—often within seconds.

A: Typical secondary systems can achieve up to 20 dB of additional reduction (perceived as up to a 75–90% drop in loudness) depending on your existing window performance, the air gap depth, and perimeter sealing. Larger air gaps (3–6 inches) generally improve low-frequency control (trucks, trains), while acoustic laminated glass excels at mid/high frequencies (voices, sirens). Real-world outcomes also depend on wall construction, spandrels, vents, and flanking paths (e.g., through walls or HVAC). The bottom line: with a well-designed secondary window, intrusive street noise becomes a background hush.

A: Installations are performed entirely from the interior, avoiding scaffolding and exterior access. After precise site measurements, we fabricate your units and return for a scheduled install. Our technicians prepare the opening, place shims as needed, anchor the frame into the surrounding jambs (not the primary window), set the sash, and apply continuous compression gaskets. We protect finishes, vacuum as we go, and coordinate with property management to minimize disruption—most rooms are completed in hours, not days. Because the system is independent, your original window remains untouched and operable; we do not drill into or modify historic sashes or curtainwall framing. If you ever relocate, many configurations are removable and can be reinstalled elsewhere, making them ideal for leased spaces.

A: Every opening is different, so we tailor each unit. Glass options include acoustic laminated (varied thickness/interlayers), low-e for energy savings, security interlayers, and tinted or privacy glass. Air gap depths are selected to target your dominant noise frequencies. Frame profiles come slim for minimal sightline impact or robust for wide spans; all are powder-coated in standard or custom colors. Operation choices: fixed (maximum performance), side/top-hinged for access, lift-out for seasonal use, or acoustic sliders where daily operation matters. Frames are available in a variety of colors.

A: Properly designed, it improves thermal comfort and energy performance. The added airspace acts like an insulating layer, reducing drafts and surface temperature swings, which helps HVAC run more efficiently. To prevent condensation, we manage interior humidity, specify warm-edge spacers where applicable, and select glass/air gaps to keep interior surfaces above dew point in your climate.

A: Our secondary windows are built for decades of service. Frames are aluminum with baked-on powder coat; seals use long-life compression gaskets that resist compression set. Acoustic laminated glass features a PVB or ionoplast interlayers that not only improves sound control but also adds safety and UV filtering. Routine care is simple: clean glass and frames with non-abrasive agents and periodically wipes the gaskets. Inspect latches annually to ensure proper compression; we can provide a preventive maintenance plan for larger properties. Unlike some magnetic DIY panels, our engineered systems won’t yellow, warp, or fall out under repeated use. DDS backs installations with a product and workmanship warranty, and we stock common replacement parts. If space use changes (e.g., converting offices to guest rooms), we can re-tune panels or swap glass types to match new acoustic goals, protecting your investment over time.