Building services
Mechanical plant you can specify, and then not hear.
Noise criteria definition, duct and silencer design to ASHRAE and CIBSE methods, and vibration isolation from fan coil units to 2,000 kVA generators.
The problem this solves
The most common acoustic failure in finished buildings is mechanical: a rooftop chiller that keeps a penthouse awake, an AHU that pushes a boardroom past its NC target, a generator whose vibration travels three floors. These failures are systematic and preventable. Set the right criteria per space, design the airpath and the isolation to meet them, and verify at commissioning.
What we deliver
HVAC noise criteria definition (NC and NR) for all space types. Duct design and silencer and attenuator sizing. Vibration isolation and noise control design for AHUs, chillers, fans, pumps, and generators. Fan coil and VRV and VRF acoustic compliance assessment. Elevator noise and vibration design and commissioning criteria. Rooftop plant compound assessment with our 3D modeling where the risk extends beyond the building.
Method and standards
Duct and silencer design follows the ASHRAE HVAC Handbook Chapter 48 and CIBSE Guide B5. Criteria are set per space against NC and NR curves, and compliance is verified at commissioning through diffuser noise checks and silencer insertion loss validation by our own testing team.
How this scope is appointed: usually as a sub-consultant to the MEP engineer, directly by the developer where plant noise is already a problem, or as an independent review of a selection that has already been made.
Already holding a plant selection and a noise target that do not agree? Describe the space and the machine.
Proof
HVAC acoustic design for the Marina Tower penthouse in Lebanon to meet NC targets. Rooftop HVAC noise and vibration isolation at AUBMC and CMC Clinics. Chiller compound noise and vibration mitigation protecting penthouses at the Tribute Portfolio Resort. HVAC noise control across the Waldorf Astoria Al Madinah plant schedule.
Questions we are asked
What NC level should a guest room meet?
Typically NC 25 to NC 30 depending on the operator standard. We define the criterion per space and design to it.
Can you fix an existing noise problem?
Yes. Diagnosis by measurement, then targeted mitigation, as in our chiller remediation protecting occupied floors at the Tribute Portfolio Resort.
Which standards govern the design?
The ASHRAE HVAC Handbook Chapter 48 and CIBSE Guide B5 for airpath noise, with vibration isolation assessed against BS 6472 where human exposure in buildings is the concern.
Related services: Industrial Acoustics and Power Generation Acoustic Testing and Commissioning
Send the plant schedule and the space list and we will set the criteria against them.