S03: Sound Barriers – Above Green

(3 points)

INTENT

Increase the level of speech privacy between horizontally adjacent enclosures and highlight design constraints that may hinder acoustical comfort.

SUMMARY

This WELL feature requires design- and performance-based compliance that projects can adhere to in order to bolster acoustical privacy between rooms. This feature can operate in tandem with Feature S01: Sound Mapping by introducing the specific performance metrics of partition acoustical performance criteria and privacy [e.g., Noise Isolation Class (NIC), Sound Insulation (D_w), Speech Privacy Potential (SPP)].

ISSUE

The sound that transmits through partitions that lack acoustical performance can be highly distracting for people who may be located in the adjacent room. This is most noticeable across partitions that separate sensitive spaces that require lower background noise levels (e.g., human resources, legal, AV-equipped conference rooms, wellness rooms, bedrooms, classrooms). As lightweight construction and demountable partitions become the norm in typical architectural design, there is still a need for greater acoustical privacy that can only be provided by less visibly transparent building materials with greater mass. There is evidence that suggests if occupants know that their room is not private (i.e., that sound transmits readily from one room to another), they will be less inclined to divulge personal information to a doctor, colleague, family member etc. When an enclosed, private office allows sound to be transmitted easily, the expectation of privacy is stunted unless acoustical treatment is provided.

SOLUTIONS

Sound has the ability to transmit readily between enclosed spaces if proper acoustical reinforcement is not provided. Controlling the transmission of noise across separating media is crucial in supporting privacy between rooms. Typical partition constructions can be reinforced with privacy in mind to increase the acoustical performance between spaces. One best practice solution for increasing privacy between rooms is increasing the mass of a given partition by providing additional laminations, insulation and/or airspace to interrupt the transmission of sound. Sound can also flank across openings above finished ceilings, imperfections in partition construction and through floors, doorways and windows. Such flanking can be avoided by sealing imperfections in construction and closing any penetrations that may exist in, around or above partitions. While this approach to privacy may seem easier for new construction, acoustical abatement does exist for retrofitting instances where existing partition construction is lacking in the necessary performance for existing fit-outs. A sealant can be provided at partition imperfections, mass-loaded vinyl can be used above partial height partitions to block sound and doors can be provided with gaskets and seals. Lastly, where partition performance may lack, intentional background noise via a dedicated sound masking system can be introduced to bolster the overall SPP in any given receiver location.

IMPACT

Increasing privacy between spaces, especially sensitive spaces, has the potential to reduce distraction or disturbances that external noise sources may cause for occupants.

REQUIREMENTS

Part 1

Ensure Adequate Wall Construction (2 points)

Verified by Performance Test, Design Specifications

For Office Spaces

The following is achieved:

In the spaces listed below, the sum of the background noise level (NC or NR) and sound insulation across a partition (NIC or D_w) meets the minimum SPP ratings listed in the table:

Source Room	Receiving Room	Minimum SPP
Enclosed Offices	Enclosed Offices	75
	Conference Rooms	80
	Open Offices	70
Conference Rooms	Enclosed Offices	85
	Conference Rooms	80
	Open Offices	70
Enclosed Quiet Zones (identified through S01: Sound Mapping, Part 3: Label Acoustic Zones)		75

Note: SPP is the sum of the noise reduction across a partition and the background noise level within a receiving space.

For walls that include a sliding door, decrease the SPP threshold by 5 (e.g., SPP 65 between enclosed source room and open office receiving room).

Performance verification is only required for offices. Dwelling units and educational facilities must only submit a Letter of Assurance by the Architect.

For Dwelling Units

Dwelling unit partitions are constructed to meet the following requirements:

Minimum STC-50 for demising walls that separate dwelling units from other units and corridors.
Minimum STC-45 for walls that separate bedrooms from other rooms within a given dwelling unit.

For Classrooms

Student Classrooms:

Partitions in schools are designed and constructed to meet the following requirements:

Minimum STC-45 for walls that separate classrooms from corridors, staircases, offices or conference rooms.
Minimum STC-50 for walls that separate classrooms from classrooms, therapy rooms and healthcare rooms.
Minimum STC-53 for walls that separate classrooms from bathrooms.
Minimum STC-60 for walls that separate classrooms from music rehearsal or performance spaces, auditoriums, mechanical equipment rooms, workshops, cafeterias, gymnasiums or indoor swimming pools.

Part 2

Ensure Proper Door Specifications (1 point)

Verified by Design Specifications

For All Spaces

Doors which connect private offices, conference rooms, classrooms and dwelling units to other spaces are constructed with two of the following requirements:

Minimum STC-30 acoustical performance.
Gaskets at the head and jambs.
Automatic drop seal or sweep at base.
A non-hollow core door.