Soundproofing Walls and Ceilings in Your Gym

gym soundproofing tips

From SoulCycle to Barre to Zumba, it seems like there’s a new workout craze every week these days, and with all these fitness classes come new gyms on every corner.

Blaring music, loud equipment and stamping feet may pump you up while you work out but for the daycare center and office building next door, the constant noise can be problematic to say the least.

So what can these gyms do to combat noise complaints and keep their neighbors happy? Soundproof, of course!

Floors

Gyms are typically built with hard flooring to fight against damage from heavy equipment. This type of flooring may be great for protecting against dropped weights, but sound easily echoes off of these hard surfaces, creating a lot of extra noise, especially for your downstairs neighbors.

To muffle sound without sacrificing tough flooring, install sound dampening composites directly onto bare floors for an overall quieter structure.

Walls

Many gyms are located in places with thin walls, like strip malls, which do nothing to stop noise from traveling between facilities.

To stop noise from seeping through the walls and into your neighbors’ space, consider hanging “acoustical wallpaper,” which will suppress sound from moving through even the thinest of walls. This one is easy to install and can even be primed and painted over, so you don’t have to sacrifice style when soundproofing.

Ceilings

If you’re gym is located in a multi-story facility, you’re likely irritating your upstairs neighbor with every class you offer.

By installing these noise-blocking panels to your ceiling, you will stop noise from escaping through to the floors above you.

If your gym is constantly fielding noise complaints from angry neighbors looking for some peace and quiet, it may be time to start soundproofing. By following these easy tips, you’ll be able to easily trap noise in and keep your bothered neighbors at bay.

Understanding Expected IIC and STC of Assemblies – Case Study

An architectural firm in Florida is undergoing the process of reviewing standard details in their design assemblies, including the expected IIC and STC of these assemblies. Since these details are used on a number of developments, it is critical to understand how these details are performing in the field, and compare those against the expected values in the laboratory tests.

A drawing package review was completed prior to the site visit. Testing was performed with representation from the Architecture team and Construction team present.

This report includes findings from the design review and site observations, as well as all testing data compiled in Appendices A-E.

Findings

  1. WF-9 Tenant-to-Tenant Wall

The first test was conducted on WF-9 Tenant-to-Tenant Double-Stud Wall (Appendix A). This wall had a 10” top plate spanning the two sets of 2×4 studs. The shared top plate diminishes the sound-blocking capacity of this wall from an STC 55 to STC 51 (see Appendix H, figures 10 and 11) below, since it allows direct propagation of noise through the wall along the top plate. Since there is only a top plate connection, and no bottom plate, the expected STC may be closer to 53. Upon discussing with the architect, this top plate is necessary for fire-stopping and draft control. However, if another means of fire stopping may be implemented, such as plugging the 2” air gap with plywood, then the wall may perform closer to its lab value.

After the field test was complete, a leak check was performed on this wall, to determine if more sound was transmitted through it in some locations than others. The SPL (Sound Pressure Level) Meter peaked about 3-5 dB at the base of the wall, indicating there was some flanking at this location. While not as significant as some field tests, adding a thin bead of acoustical sealant just along the bottom of the wall may improve the field STC of the system by several points.

Overall, the ASTC of 50 is above the Florida Building Code minimum.

  1. WF-4 Breezeway Corridor-to-Unit Wall (Kitchen)

The next test was conducted on WF-4 Breezeway Corridor-to-Unit Wall (Appendix B). This wall utilizes resilient channel, but the contractor also used blocking to support cabinets in the kitchen. This compromises the integrity of the resilient channel, which works by decoupling the drywall from the studs. By screwing into the blocking through the drywall, the effectiveness of the resilient channel is greatly reduced.

While an STC of 56 is indicated on the Wall Schedule, no Acoustic Test # is referenced, unlike Acoustic Test # TL-93-265 which was referenced in WF-9 in the wall schedule (See Figures 1 and 2 below).

The attached Figure 12 in Appendix H indicates that this assembly will test to an STC of 50.

As a rule-of-thumb, STC ratings referenced in the wall schedule should have the accompanying Acoustic Test # available for review. The actual Acoustic Lab Test report should also be provided in the design package when possible.

The door appeared to be the primary flanking path in the kitchen. A door STC specification was requested from the construction submittal package, and is included in Appendix F. The STC of 24 for the door is much less than the STC of 50 for the walls. Using a heavier-gauge door, and improving the weather stripping to acoustic seals and sweeps would further improve the performance of this wall system.

Figure 1: WF-4 From Wall Schedule

Figure 2: WF-9 From Wall Schedule

    3. WF-4 Breezeway Corridor-to-Unit Wall (Closet)

As a control, a field test was performed on WF-4 between the unit closet and corridor. While there was substantially less wood blocking used in the closet, due to the lighter weight shelves compared to the kitchen cabinets, it still appeared to affect the performance of the wall assembly.

The ASTC of 43 is slightly below the Florida Building Code allowable limit.

To improve the ASTC of the wall, a different resilient mount system may be used (such as Genie Clips) or a differing wall system that incorporates a soundproofing membrane rather than a resilient mount. See Appendix G for options.

4. Kitchen Flooring (FC-1)

The Kitchen Floor was tested, and results are available in Appendix D. The flooring system consisted of 20mm thick wear layer Luxury Vinyl Tile, ¾” Gypcrete, AccuQuiet D18, ¾” OSB, 20” deep Wood Floor Truss, R-13 Batt Insulation and Resiliently Mounted 5/8” Type X Drywall.

There were a few concerns associated with the location of the underlayment:

  • The underlayment was used under the Gypcrete layer, but was only located under the section of the floor where LVT was used. This creates a number of flanking paths. For instance, structure-borne noise (from footfall or other sources) may travel through the Gypcrete, around the underlayment, and into the OSB subfloor. This bypasses the underlayment layer, reducing the effectiveness of the floor. Furthermore, since the underlayment is below the Gypcrete, additional layers cannot be added in the future, and it cannot be used to spot-treat as a topical sound mat can. Overall, this type of underlayment is effective, but must be used throughout the entire area where the Gypcrete is isolated.
  • The Floor Perimeter Isolation Strips were only installed in the kitchen area. This introduces additional flanking paths. Also, it makes it very difficult to retrofit the apartment for future purposes, since removing the carpet for LVT would then be well below the Building Code requirements.

Beyond the location of the underlayment, the product selection raised a few questions. Upon inspecting the submittals and contacting the manufacturer, there was no acoustical testing available for the AccuQuiet D18. While the manufacturer claims it may improve IIC from 6-12 points, no further testing or documentation was available.

Figure 3: AccuQuiet D18 Sound Mat – Specifications

There is no Acoustic Test listed in the Construction and Referenced Assemblies (A 1.04A). Similar to the wall assemblies, an IIC and STC of the floor should be made available in the design package.

The AIIC of the floor was measured at 43, which is below the Florida Building Code.

5. Living Room Flooring (FC-1)

The Kitchen Floor was tested, and results are available in Appendix E. The flooring system consisted of Carpet with Padding, ¾” Gypcrete, ¾” OSB, 20” deep Wood Floor Truss, R-13 Batt Insulation and Resiliently Mounted 5/8” Type X Drywall.

The AIIC of the floor was measured at 58, which meets and exceeds the Florida Building Code.

Conclusion & Recommendations:

Overall, of the 5 tests conducted, 2 tests met the Florida Building Code, Section 1702.2 and 1702.3 for Sound Attenuation. The tests that did not meet the Building Code were the Floor-Ceiling test in the Kitchen, Corridor-Unit test in the Kitchen, and Corridor-Unit test in the Closet.

The tests that did not meet code were generally within a few points of the field test requirement, which is an ASTC and AIIC of 45.

Options to consider for further improvement of acoustical performance include:

  1. Specify an acoustically-rated underlayment under the Luxury Vinyl Tile in the kitchen and bathrooms, and include the lab test and floor IIC ratings in the Floor Schedule (see Appendix G)
    1. If using a sound mat under the gypcrete, ensure it is used throughout the entire space, and ensure perimeter isolation strips are used, to prevent flanking
    2. If using a sound mat above the gypcrete, this is not necessary
  2. Remove the shared Top Plate on the Double-Stud Wall Assembly and instead meet the fire blocking requirements with a separate material along the top
  3. Use a different assembly for the corridor-unit wall that does not rely on resilient channel, since this is compromised by the use of blocking in the closet and kitchen
  4. Add thicker, acoustically-rated weather stripping (door seals and sweeps) to the front door to reduce corridor-unit noise transfer
  5. Use a thicker, heavier-gauge door in the kitchen to reduce transmission through the door

Conclusion & Recommendations:

Overall, of the 5 tests conducted, 2 tests met the Florida Building Code, Section 1702.2 and 1702.3 for Sound Attenuation. The tests that did not meet the Building Code were the Floor-Ceiling test in the Kitchen, Corridor-Unit test in the Kitchen, and Corridor-Unit test in the Closet.

The tests that did not meet code were generally within a few points of the field test requirement, which is an ASTC and AIIC of 45.

Options to consider for further improvement of acoustical performance include:

  1. Specify an acoustically-rated underlayment under the Luxury Vinyl Tile in the kitchen and bathrooms, and include the lab test and floor IIC ratings in the Floor Schedule (see Appendix G)
    1. If using a sound mat under the gypcrete, ensure it is used throughout the entire space, and ensure perimeter isolation strips are used, to prevent flanking
    2. If using a sound mat above the gypcrete, this is not necessary
  2. Remove the shared Top Plate on the Double-Stud Wall Assembly and instead meet the fire blocking requirements with a separate material along the top
  3. Use a different assembly for the corridor-unit wall that does not rely on resilient channel, since this is compromised by the use of blocking in the closet and kitchen
  4. Add thicker, acoustically-rated weather stripping (door seals and sweeps) to the front door to reduce corridor-unit noise transfer
  5. Use a thicker, heavier-gauge door in the kitchen to reduce transmission through the door

Appendix A: ASTC Test – Wall Between 4206 Living Room and 4207 Living Room

Figure 4: ASTC of Wall Between 4206 Living Room and 4207 Living Room

 

Appendix B: ASTC Test – Wall Between 4206 Kitchen and Corridor

Figure 5: ASTC of Wall Between 4206 Kitchen and Corridor

 

Appendix C: ASTC Test – Wall Between 4206 Bedroom and Corridor

Figure 6: ASTC of Wall Between 4206 Bedroom and Corridor

Figure 7: AIIC of 4206 Kitchen and 4106 Kitchen (Luxury Vinyl Tile)

Appendix E: AIIC Test – Floor Between 4206 Living Room and 4106 Living Room (Carpet)

Figure 8: AIIC of 4206 Living Room and 4106 Living Room (Carpet)

 

Appendix H: Supporting Lab Testing

Figure 10: Lab STC of Double Wood-Stud Wall

Figure 11: Simulated STC of Staggered Wood-Stud Wall with Shared 10” Top Plate

Figure 12: Lab STC of Wood-Stud Wall with Resilient Channel

 

Cancer Treatment and Research Center – Case Study

A cancer treatment and research center is undergoing a renovation to replace wood flooring with terrazzo. The reverberation in this space has already raised some complaints, and the more reflective floor covering is expected to create more. These issues are most noticeable during events hosted in the atrium with amplified loud speakers.

A reverberation test was set up in the main atrium to determine the reverberation at A-weighted frequencies and speech frequency ranges.

Test Method:

3 different impulse noises were used as the noise source. First, a loud speaker with white noise was cut off to allow measurement of reverberation. Secondly, hand claps were used as an impulse. Both methods failed to produce conclusive readings in the frequencies below 1000 Hz. Finally, 2”x4” wood studs were clapped together to create the noise source. The results were averaged together to yield the RT60 (“reverberation time”) value at each location.

A Type 1 SPL (Sound Pressure Level) meter was used to capture the amount of time it took the initial noise to decay by 60 dB at each frequency range. These results are displayed below in Table 1.

Test Results:

Location

800 Hz

1 kHz

1.25 kHz

1.6 kHz

2 kHz

2.5 kHz

3.15 kHz

4 kHz

5 kHz

6.3 kHz

RT60

Point 1

3.41

3.16

3.21

2.97

2.78

2.42

2.27

2.3

1.89

1.44

2.8

Point 2

3.51

3.13

2.67

2.58

3.14

2.33

2.04

1.88

1.73

1.26

2.67

Point 3

2.71

2.62

2.48

2.53

2.25

2.04

2.11

2.01

1.6

1.39

2.39

Point 4

3.95

3.9

2.48

2.61

2.46

2.25

2.13

2.11

1.75

1.5

2.47

Point 5

3.68

2.82

2.97

2.75

2.37

2.28

2.13

2.03

1.78

1.34

2.59

Average Reverb

2.58

Table 1: Reverberation Results

Figure 1: Reverberation Test Locations

Figure 2: Reverberation Criteria with Various Venues

Recommendations:

In order to achieve a desired reverberation time of 1.45-1.9 seconds for a multi-purpose auditorium or venue, additional absorption materials will need to be added to the space.

After discussion with the client, it appears that installing these closer to the floor will yield significant savings due to the 56’ height of the room.

Using a simple Sabins calculation, the use of 48 panels at 2’x4’x2” thick, with an absorption factor of 1.05 NRC, will be sufficient to reduce the reverberation down to acceptable levels. While this characterization may be over-simplified due to the cavities and non-parallel surfaces in the space, it has been normalized to the readings taken in the field.

The Salvador – Multifamily

When developing luxury hotel and condo units, sound transmission and privacy are a top concern.

During the design of luxury spaces the target STC for demising walls are typically above the STC 50 minimum, and are closer to 53-58 depending on location and luxury standards.

Instead of adding multiple layers of drywall to the assembly or using double studs to improve sound transmission, The Salvador in St. Petersburg chose to use Commercial Acoustics Wall Blokker sound membrane.

The Salvador is a 13-story green certified building which houses 74 luxury condo units and is located in the heart of downtown St. Pete.

Marchman Technical College – Educational, Acoustical Absorption

Noise control and sound privacy within educational settings are imperative. During the design process, target STC’s for walls should be discussed and mandated by the architect, but oftentimes topical acoustical treatment for larger spaces is held until after construction is complete. With the hard, reflective surfaces present within gymnasiums, cafeterias, and auditoriums, acoustical absorption is needed to maintain speech intelligibility and reduce reverberation.

The architects for Marchman Technical College consulted with Commercial Acoustics for their cafeteria space, where we supplied them with 100 PVC-wrapped baffles to absorb soundwaves. After installing the baffles, reverberation in the cafeteria space was significantly reduced and sound privacy was finally reestablished.

Luxury Timeshare Case Study – Orlando, FL

Testing and analysis were performed for a luxury timeshare in Orlando,

2 walls were tested: The wall between units 209A and 210A and the wall between 211A and 212A.

Both tests were performed late in the afternoon, around 5PM, when the construction on the adjacent job site was sufficiently low, but at times, still audible.

 

Description of Tests (2):

  1. Airborne Test (ASTC) was performed in accordance with ASTM E336 between units 209A and 210A in their respective kitchen/living room areas
    • This test was used to determine how much sound the wall assembly blocks between adjacent A Units.
    • The wall assembly tested was:
      • 1 Layer of 5/8” Type X Drywall Each Side, 1 Layer of 1/8” Wall Blokker Membrane One Side, 25-Gauge Steel Studs 16” o.c. and R-13 fiberglass insulation batting in the cavity
      • The wall assembly also included a hollow-core door in the center, a 4” air gap, and another hollow-core door. Each door had automatic door sweeps that were engaged.
  2. Airborne Test (ASTC) was performed in accordance with ASTM E336 between units 211A and 212A
    • This test was used to determine how much sound the wall assembly blocks between adjacent A Units.
    • The wall assembly tested was:
      • 1 Layer of 5/8” Type X Drywall One Side, 2 Layers of 5/8” Type X Drywall One Side, 25-Gauge Steel Studs 16” o.c. and R-13 fiberglass insulation batting in the cavity
      • The wall assembly also included a hollow-core door in the center, a 4” air gap, and another hollow-core door. Each door had automatic door sweeps that were engaged.

Summary Findings & Recommendations:

The two tests had very similar results, due at least in some part to hollow-core doors in the center of each wall. The test with the soundproofing membrane did perform at 2 points higher, achieving an ASTC (Field or Apparent Sound Transmission Class) of 46, while the gypsum-only wall achieved an ASTC of 44. The Florida Building Code, Section 1207.2, requires an ASTC of 45 for walls between adjacent dwelling units.

After testing was complete, a brief leak check was performed to determine where the majority of the sound was located. In the case of the first room, the sound level at the wall was 60.8 dBA, but reached 69.8 at the base of the door. The second unit had similar results.

Ultimately, combining the wall containing the soundproofing membrane with solid core doors between the units, and ensuring the door sweeps are adequately sealed, may result in an ASTC of 50 or more.

Figure 1: Door Sweep from 3” off of ground

 

Figure 2: Door Sweep from 1” off of ground

 

As you can see in the images above, the door sweeps may appear to be engaged just a few inches off the ground. However, by laying flat, you may be able to see any small gaps or “tilted” engagement of the sweep in a closed door.

 

Sarasota Aerospace Office

Testing and analysis were performed for a property manager working for a commercial property. One of their commercial tenants, an aerospace center at the property had concerns about sound attenuation between adjacent tenant units. Two adjacent legal firms, with very low background noise in their offices, could occasionally hear muffled conversations being held in the office next to them.

3 Airborne Tests were performed in accordance with ASTM E336.

  1. Between Suite 840 and 860, the eastern-most office
  2. Between Suite 800 and 840
  3. Between adjacent office space within Suite 840

 

Description of Tests:

3 Tests were performed at the property

Test #1: ASTC Test between Suite 840 and Suite 860

  • Measured ASTC of 43
  • Receiving room – general description: The room was furnished, with carpet and acoustic ceiling tile.
  • Source Room – general description: The room was furnished, and filled with numerous files and cabinets. It was an active legal office.
  • Relationship between rooms: The Source room was located directly adjacent to the receiving room and shared a wall.
  • All adjacent spaces were closed off with doors during testing.
  • Description of Test Assembly
    • 25 Gauge Metal Studs
    • 5/8” Type X Gypsum Board Each Side
    • R-13 Batting in Studs

Test #2: ASTC Test between Suite 840 and Suite 800

  • Measured ASTC of 39
  • Receiving room – general description: The room was furnished, with carpet and acoustic ceiling tile.
  • Source Room – general description: The room was lightly furnished. It was an empty office.
  • Relationship between rooms: The Source room was located directly adjacent to the receiving room and shared a wall.
  • All adjacent spaces were closed off with doors during testing.
  • Description of Test Assembly
    • 25 Gauge Metal Studs
    • 5/8” Type X Gypsum Board Each Side
    • R-13 Batting in Studs

Test #3: ASTC Test within Suite 840, between a conference room and an empty office on the westward side of the conference room.

  • Measured ASTC of 37
  • Receiving room – general description: The room was furnished, with carpet and acoustic ceiling tile. One line of walls was thin glass, while the opposite wall was windows looking out over the street below.
  • Source Room – general description: The room was lightly furnished. It was an empty office.
  • Relationship between rooms: The Source room was located directly adjacent to the receiving room and shared a wall.
  • All adjacent spaces were closed off with doors during testing.
  • Description of Test Assembly
    • 25 Gauge Metal Studs
    • 5/8” Type X Gypsum Board Each Side
    • R-13 Batting in Studs

Summary:

The design and construction of the walls tested is sufficient to meet the needs of most office tenants.

There are few attenuation codes defined and available for commercial office applications, and no attenuation building requirements.

Per one leading publication (Architectural Acoustics, Marshall Long), the recommended Field STC (now titled ASTC) for Normal Privacy at Normal Voice Levels is 32. Furthermore, Confidential Privacy may be attained at Normal Voice Levels with an ASTC of 38. All 3 of the walls tested meet or exceed this criteria.

Table 1: STC ratings needed to achieve Privacy at Normal and Raised Voice Levels

If further improvements are required by the tenant, they should be focused on the mullions and baseboards, and if significant improvement is needed, then a topical solution on the walls will provide a 4-8 STC improvement above the current configuration. Sound Masking is also a feasible solution, but should only be considered once mullion flanking is reduced to minimal levels.

Findings & Recommendations:

After ASTC testing was complete, we also performed leak checks along the wall in each of the 3 locations. In all 3 circumstances, significant flanking occurred along the mullions on the dividing walls, as well as secondary flanking along the baseboards.

No flanking was apparent along the ceiling. Walls continued up to the deck above the Acoustic Ceiling tiles. We used ladders to inspect the duct and piping penetrations, and all were visibly sealed with batting and caulk. Workmanship in this area was better than we usually see for ducting and piping penetrations.

1. Mullions: In all 3 tested locations, the sealing around the mullion appeared to be airtight. In these cases, the mass of the mullion alone (1/8” extruded aluminum) was insufficient to attenuate the same amount of noise as the metal-stud wall. In this case, the sound traveled the path of least resistance through the mullion itself. In a nearby, untested area there appeared to be a small gap in the mullion gasket.

  • Recommendation 1: The overall goal is to add further mass to the mullion. This is a perimeter, pre-constructed member, so modifications being made should be fully-reversible and made as a last resort. That being said, if there is an option to drill holes into the mullion and add blow-in insulation or other filler that will act to improve the performance.
  • Recommendation 2: Another option would be to adhere a thin membrane (Mass Loaded Vinyl, Wall Blokker, etc.) to the mullion on each side. These membranes are 1/8” thick and may be coated to match the existing

2. Baseplates/Bottom Tracks: In each testing area, there was some secondary flanking through the baseboards.

  • Recommendation: Remove the baseboards and apply acoustical sealant along the bottom of the drywall to make this gap as air-tight as possible.

3. Walls: While the walls themselves are sufficient to meet most client’s needs and expectations, additional soundproofing may be required in special circumstances (especially where confidential or private information is being shared). In this case, there are a few options:

  • Recommendation 1: Add a layer of mass-loaded membrane directly on top of the surface. This may be done rather economically, but outlets and other penetrations along that wall will need to be extended. Thickness of the membrane is only 1/8” thick, and should be applied along the entire surface. Expected sound-blocking increase is 20-30%.
  • Recommendation 2: Add a 2nd layer of drywall on top of the existing surface. The STC increase will not be quite as much as a membrane layer, but may be quicker to install. Expected sound-blocking increase is 15-25%.
  • Recommendation 3: If both of these options are undesirable, then consider implementing a sound-masking solution in the adjacent offices to minimize the speech intelligibility and articulation index of those next door.

Orlando Condominiums

The Cayman Condominiums were undergoing a renovation, its first in 20 years. While the existing structure and design were acceptable from an aesthetic and functional perspective, the contractor felt that they needed to address the one major complaint they were receiving – noise.

Metal stud walls helped reach STCs in high 40’s and low 50’s, but the residents at this luxury location had higher expectations. During the renovation, they called Commercial Acoustics to review the existing design and as-builts, and bring some new ideas to the table.

While implementing a soundproofing membrane in the walls allowed a significant increase in attenuation between units, we also worked with the architect to re-specify doors that would not allow weak-link propagation paths from room to room (a major complaint that previous tenants had).

While the flooring contractor was already familiar with our attenuation underlayment, we still had a technical rep out on site to ensure flanking paths were addressed and installation quality met our standards.

By implementing additional soundproofing materials and auditing installation techniques, our team was able to achieve STC and IIC ratings in the unit at 58 and 60, respectively.

Tampa Office Acoustics

An open office area was struggling with reverberation in their space and called Commercial Acoustics to help. We visited and found that unlike most open offices, that have issues with sound masking and speech privacy, this office setting did truly have unwanted echo in the space. This was due to a thin carpet, corrugated metal deck, and painted drywall.

Our team fabricated acoustic panels, baffles, and clouds, and used them in the space to deaden the excessive reverberation. We self-performed the install over a few hours, and finally provided their employees and staff the acoustical peace they were looking for.