Construction Guides Construction Detail

Junction & Isolation Details

Wall junctions, vibration control, and maintenance access for acoustic integrity. Every connection point is a potential sound leak — this guide covers each one.

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Junction Types
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IDU Units
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Structural Columns
BUILDER CUSTOMIZATION GUIDE -- JUNCTION ISOLATION

CUSTOMIZABLE -- Sealant gun brand, backing rod manufacturer, surface preparation tools, visible trim and cover strips at exposed junctions (colour and profile).

DO NOT ALTER -- Isolation gap widths between wall and floor/ceiling, resilient channel and clip placement at junctions, sealant type and bead dimensions, acoustic caulk specifications, double-stud separation distances at partition intersections, floating floor perimeter isolation strip material and thickness, ceiling plenum barrier continuity at wall heads. Junction details are the critical path for maintaining STC continuity between assemblies.

Junction Details

Connection Types

Wall-Floor Junction

Most Critical

STRUCTURAL SLAB (CONCRETE) Sylomer SR 28 @ 400mm spacing PLYWOOD 1 PLYWOOD 2 (staggered joints) STUD TRACK ROCKWOOL 2x GYPSUM 10mm 5mm gap sealed ACOUSTIC SEALANT Tremco Acoustical STUD ON PLYWOOD WALL-FLOOR JUNCTION CROSS SECTION

Wall-Floor Junction — Cross Section View

Layer-by-Layer Build-Up

# Layer Material Thickness Product Critical Note

Critical Construction Rules

! Float floor MUST be continuous under wall — stud sits ON plywood, NOT on slab
! 10mm perimeter gap maintained on ALL edges — filled with acoustic sealant, NOT foam
! No rigid fasteners through float floor into structural slab

Wall-Ceiling Junction

Plenum Critical

STRUCTURAL SLAB ABOVE PLENUM SPACE 60cm HEAD TRACK (FLOATING) NO FIX RESILIENT CHANNEL GYPSUM TO PLENUM PLENUM BARRIER FIRE-RATED SEALANT SUSPENSION GRID ACOUSTIC CEILING TILE ROOM BELOW 60cm WALL-CEILING JUNCTION CROSS SECTION

Wall-Ceiling Junction — Plenum Detail

Layer-by-Layer Build-Up

# Layer Material Product Critical Note

Critical Construction Rules

! Head track floats — NO screws into structural slab above
! Gypsum extends above ceiling line into plenum as continuous barrier
! All plenum gaps sealed with fire-rated acoustic caulk at every joint

Wall-Wall Corner Junction

Decoupled

WALL A GYPSUM (CONTINUES PAST CORNER) WALL B GYPSUM ACOUSTIC SEALANT at all junctions STUD FRAMING NOT INTERLOCKED 400mm OC Wall A gypsum Wall B gypsum Acoustic sealant WALL-WALL CORNER — PLAN VIEW

Wall-Wall Corner — Plan View (Top Down)

WALL A GYPSUM (continues past corner) WALL B SEALANT BEAD Wall B butts into Wall A CORNER JUNCTION — ISOMETRIC VIEW

Wall-Wall Corner — 3D Isometric View

Layer Sequence

# Layer Detail Critical Note

Critical Construction Rules

! Stud framing must NOT be interlocked between perpendicular walls
! Wall A gypsum continues past the corner — Wall B gypsum butts against Wall A face
! Acoustic sealant bead at every gypsum-to-gypsum junction, full height

Buffer Spine Intersections

Isolation Core

BUFFER SPINE STC 55 GREEN GLUE FULL-HEIGHT ACOUSTIC SEALANT NO MECHANICAL CONNECTION THROUGH GAP PARTITION WALL (terminates at buffer face) VO LIVE STUDIO CONTROL EDITING 15cm BUFFER INTERSECTION — PLAN VIEW

Buffer Spine Intersection — Plan View

FLOAT FLOOR 2x12.5mm GYPSUM + GREEN GLUE 70mm STUDS + ROCKWOOL PARTITION FULL-HEIGHT SEALANT AIR GAP CONTINUOUS floor to ceiling CEILING LEVEL BUFFER AT PARTITION — VERTICAL SECTION

Buffer Spine at Partition — Vertical Cross Section

Layer Sequence

# Layer Detail Critical Note
Buffer Construction

Critical Construction Rules

! Partition wall NEVER passes through buffer air gap — terminates at buffer face only
! All connections to buffer surface only — sealed with acoustic sealant, full height
! Buffer air gap must remain continuous from floor to ceiling — no bridging at any point
Vibration Control

Equipment Isolation

Mechanical equipment produces vibration that can transmit through structure. Every IDU, ODU, and connection must be vibration-isolated.

IDU Mounting Detail

CEILING STRUCTURE SPRING HANGERS IDU UNIT NEOPRENE MOUNTS FLEX DUCT FLEX REFRIG. CONDENSATE P-TRAP IDU CEILING MOUNT DETAIL

ODU Vibration Isolation

GROUND / EXTERIOR CONCRETE PAD RUBBER ANTI-VIBRATION PADS ODU UNIT FLEX PIPE TO BUILDING 150mm MIN CLEARANCE BUILDING STRUCTURE NO RIGID LINK ODU EXTERIOR MOUNT DETAIL

Structural Column Clearance

Walls must NOT connect rigidly to structural columns. An isolation gap is required where acoustic treatment meets column faces.

Ongoing Integrity

Maintenance Access

Acoustic isolation degrades over time if seals crack, pads compress, or penetrations develop. Regular inspection preserves performance.

IDU Access Panels

  • Ceiling access hatch above each IDU location
  • Minimum 600mm x 600mm opening for filter service
  • Hatch must include acoustic gasket seal
  • Spring hanger adjustment access from above

Silencer Access

  • Access through buffer plenum space
  • Removable ceiling panels above buffer partition wall
  • Silencer end-caps accessible for cleaning
  • Airflow verification ports at each silencer

Sealant Inspection

  • Annual visual check at all perimeter junctions
  • Look for cracks, shrinkage, or separation from substrate
  • Re-apply sealant where gaps exceed 1mm
  • Check door seals and drop-seal mechanisms

Float Floor Inspection

  • Check isolation pad compression every 2 years
  • Verify perimeter gap integrity (10mm maintained)
  • Inspect for rigid bridging (cables, pipes touching slab)
  • Test for structure-borne vibration with impact hammer
Approved Products

Material Reference

Flooring Products

Product Use Spec

Sealant Products

Product Use
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