HVAC Penetrations

HVAC installation guide covering Daikin VRF cooling, fresh air ventilation, silencer schedule, and wall penetration sealing requirements.

CONCEPTUAL ACOUSTIC REQUIREMENT ONLY

This HVAC layout is the acoustic performance requirement only. Final duct sizing, equipment selection, silencer specifications, airflow rates, pressure drop calculations, and installation drawings must be completed by a qualified MEP/HVAC engineer. The silencer attenuation values in this document are acoustic targets — they are not final engineering specifications.

MEP note: Silencer selection must be verified against octave-band noise data (63–4000 Hz) from actual fan manufacturer curves.

System Overview

System 1: Daikin VRF Cooling

Type	Variable Refrigerant Flow (Daikin VRF)
Indoor units	3 wall-mounted IDUs
IDU-04	Serves VO Live only — dedicated (north wall, west side)
IDU-03	Serves Control Room + Editing Suite — crossover duct (north wall, Control/Editing zone) ⚠ Crossover duct between Control and Editing requires 15–20 dB silencer
IDU-05	Serves Video Studio only — dedicated (north wall, Studio side)
Outdoor unit (ODU)	1 unit, south exterior wall

System 2: Fresh Air Ventilation

Purpose	Outside air supply with acoustic silencers
Distribution	Plenum-based via 50 cm ceiling plenum
Silencer runs	5 runs (A, B, B1, B2, C) — see schedule below

Silencer Schedule

Run	Serves	Length	Attenuation	Terminal Velocity	NC Max
A	VO Live (dedicated)	1500 mm	40 dB	1.5 m/s	NC-12
B	Control + Editing trunk	1000 mm	25 dB	2.0 m/s	NC-18
B1	Control branch	500 mm	15 dB	2.0 m/s	NC-18
B2	Editing branch	300 mm	10 dB	2.5 m/s	NC-25
C	Studio (dedicated)	1000 mm	25 dB	2.0 m/s	NC-18

Crosstalk Warning — Trunk B Path:

Room-to-room crosstalk between Control and Editing travels B1→B→B2 = only 25 dB isolation. Dedicated crosstalk silencers on branches B1 and B2 are recommended if simultaneous use is expected.

IDU-03 Crossover Flanking — Control ↔ Editing:

IDU-03 serves Control Room + Editing Suite via crossover duct. This creates a flanking path between the two rooms.
Mitigation: install 15–20 dB silencer on crossover duct.
Risk level: LOW-MEDIUM (NC-25 / NC-25 targets, not NC-12).

VO Live NC-12 — Achievable with Dedicated IDU-04:

NC-12 achievable — dedicated IDU-04 eliminates shared chassis flanking from Control Room. No crossover duct to VO Live.
Confirm: IDU-04 self-noise at minimum fan setting ≤ NC-12 curve with supplier.

Wall Penetration Rules

MANDATORY — All Penetrations Must Comply:

Every duct penetration: oversized sleeve with 25 mm annular gap, packed with Rockwool + sealed with acoustic sealant on both faces
No back-to-back penetrations on opposite walls — offset by minimum 600 mm to prevent direct sound path
Daikin VRF refrigerant pipes: 32 mm sleeve, foam backer rod, acoustic sealant both faces
Buffer spine = ONLY permitted duct routing path between east/west zones — no ducts through perimeter walls between adjacent rooms
Plenum barrier walls: full-height gypsum from ceiling tile to structural slab at every partition — sealed with acoustic caulk on both faces

Penetration Sealing Detail

Layer	Product	Specification
1. Sleeve	Galvanized steel	25 mm larger than duct on all sides, fixed to wall structure
2. Packing	Rockwool	Fill annular gap, compressed to 80% density
3. Sealant	Acoustic sealant (Tremco or equiv.)	Full perimeter, 25 mm depth minimum, both faces
4. MLV boot	1 lb/ft² mass-loaded vinyl	Wrap around duct ±150 mm from wall face
5. Fire collar	Intumescent collar	Both sides of wall — required for fire compartmentation

Daikin VRF Refrigerant Pipe Sealing

Layer	Product	Specification
1. Sleeve	PVC or steel	32 mm diameter, centered on pipe
2. Backer rod	Closed-cell foam backer rod	Fill annular gap, compress to contact
3. Sealant	Acoustic sealant	Both faces, full perimeter

Plenum Barriers

Barrier Location	Material	Purpose
Above buffer spine	15 mm Knauf Soundshield Plus, sealed to slab	Prevents flanking between east and west room pairs
Above VO/Control partition	15 mm Knauf Soundshield Plus, sealed to slab	Prevents flanking between VO Live and Control Room (plenum path)
Above Studio/Editing partition	15 mm Knauf Soundshield Plus, sealed to slab	Prevents flanking between Video Studio and Editing
MLV curtains at duct crossings	1 lb/ft² MLV, ceiling to slab	Acoustic curtain wraps around ducts where they cross plenum barriers

IMPORTANT DISCLAIMER: The above is the acoustic performance requirement. Final HVAC design, equipment selection, and installation drawings are to be produced by the MEP engineering team. All silencer specifications, duct sizes, and penetration locations must be verified by a qualified mechanical engineer before procurement or installation.