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Build 07 — Observation Window OW-1

2-pane, large air gap, 5° tilt, flush in the deepened 150mm W6 · click any drawing to zoom · acoustics5

What you need

1
OW-1 unit (STC 50, 80×55cm) · OW-01
Qty: 1
2-pane: 8mm float + ~110mm air + 12.8mm laminated
2
Powder-coated steel frame (~170mm) + neoprene strip · —
Qty: 1
Set flush in the 150mm wall on neoprene
3
Desiccant + absorptive reveal lining · —
Qty: 1 lot
Dry cavity; mineral-wool splayed reveal
4
Non-hardening acoustic sealant · —
Qty: 1 lot
Full perimeter (no foam, no rigid bridge)

Detail — OW-1 (click to zoom)

VO LIVE CONTROL air gap ~110mm (+ desiccant) Outer pane: 8mm float (VO side) Inner pane: 12.8mm acoustic laminated (Control) tilted 5° (one pane) — breaks parallel-pane flutter Absorptive reveal (mineral wool) lines the jamb Neoprene isolation strip frame→structure; no rigid bridge Non-hardening acoustic sealant full perimeter (NOT foam) W6 stays DECOUPLED at 150mm staggered / resilient-channel studs — never a single stud bridging both leaves W6 wall = ~200 mm (150mm studs) window ~170 mm — sits FLUSH inside the wall (no box-out) Vertical section — tilt & sill finished floor W6 below sill sill 100 cm AFF 5° head (frame) opening80 × 55 cm

Build sequence

1
Frame the flush opening

Build the window box in the deepened 150mm W6 so the ~170mm frame sits flush. Set the steel frame plumb on a neoprene isolation strip.

2
Line the reveal

Line the splayed reveal with mineral wool (absorptive) and confirm the frame is decoupled from the structure.

3
Set the outer pane

Install the 8mm float pane (VO side) on its spacer.

4
Set the inner pane (tilted 5°)

Install the 12.8mm laminated pane (Control side) tilted 5° to break parallel-pane flutter; add desiccant to the cavity.

5
Seal & inspect

Seal the frame-to-wall perimeter with non-hardening sealant; check sightline/tilt and STC certificate before sign-off.

Golden rule: Isolation lives in the air gap + asymmetric panes. Keep the gap; resolve depth with the boxed reveal, not by thinning the gap. Glazier must certify STC 50 (ASTM E90).