Sorry you're having a problem getting sound data. A lot of manufacturer's do not have data because it is an extra cost for them to get the testing performed. Your best but is to try to contact the sales rep in your area (or have the mechanical engineer contact them) and tell them you need the data. I have not had much luck getting information from Mitsubishi, personally.

Good luck!

Daikin AC typically has sound data. http://www.daikinac.com/commercial/docsOverview.asp?sec=docs

They are very similar sized unit and you may be able to substitute the data.

For best practices regarding background noises other than HVAC, refer to the ANSI S-12.60 standard. It is not required in the current version of LEED, but the standard has recommendations that will help you address that issue.

The NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. requirements in LEED aren't related to background noise, they are related to reverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) time of the room. The reverberation requirements are the same, whether you have a naturally ventilated space or a space with HVAC equipment and ducting.

Ask your mechanical engineer to look into how the calculations are performed with the software. I'm going to guess that the calculations are based on ASHRAE, the same as the TAP program, and should be fine to use.

The info might be found in the "about software" or in the documentation that came with it. Or by contacting your McQuay representative and asking them.

I haven't had any personal experience with it but it probably will give the same results as the TAP program.

Hi Alberto

Music Rooms are considered a core learning space. You are on the right track. A simple way to be back in compliance if you keep going down the Option 1 route would be to add wall panels, NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. 0.7 or better, to compensate for the missing ceiling tiles.

The other way would be to not do the wall panels and try Option 2 and make the reverb time calculations to see if you're in compliance.

Thanks for the tip Daniel, I was under the impression that you could only count material on the ceiling, makes perfect sense to be able to count wall panels as well, we should have enough in the design already to make-up for the SF in the ceiling.

Thanks.

Daniel,

After inputting the absorbent wall panels into the calculation, we are still short of the required SF. I have discussed with my acoustical consultant, and their argument is that the music room is a "special-purpose" room and therefore should not be included as part of the calculations. The room is currently optimally designed for acoustics, adding absorbing panels or removing diffusing panels would result in poor acoustical performance.

Would you agree with pursuing compliance in that manner? Trying to be very careful here since it is a PR.

Daniel,

After inputting the absorbent wall panels into the calculation, we are still short of the required SF. I have discussed with my acoustical consultant, and their argument is that the music room is a "special-purpose" room and therefore should not be included as part of the calculations. The room is currently optimally designed for acoustics, adding absorbing panels or removing diffusing panels would result in poor acoustical performance.

Would you agree with pursuing compliance in that manner? Trying to be very careful here since it is a PR.

Hi Alberto

You can definitely try that approach and write in the narrative how it is a special purpose space. I don't know how USGBC will react. The LEED documents explicitly state that music rooms are core learning spacesCore learning spaces are spaces for educational activities where the primary functions are teaching and learning and where good speech communication is critical to a student's academic achievement. These spaces include, but are not limited to, classrooms, enclosed or open plan), instructional pods or activity areas, group instruction rooms, conference rooms, libraries, offices, speech clinics, offices used for educational purposes and music rooms for instruction, practice and performance. so they might come back and ask for absorption.

Gabriela, can you clarify your question? I think that a review of the credit language above should provide the detailed clarity that you're looking for.

Hi Gabriela.

You are free to choose between complying with ASHRAE (path 1) or ANSI (path 2) based on what you feel is best for your situation. I, personally, like to follow path 1 and the ASHRAE standard because I'm familiar with the procedure and acoustic calculations, but path 2 and following the ANSI standard is also perfectly fine.

If you use Option 1 and document the NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. requirements for all of the core learning spacesCore learning spaces are spaces for educational activities where the primary functions are teaching and learning and where good speech communication is critical to a student's academic achievement. These spaces include, but are not limited to, classrooms, enclosed or open plan), instructional pods or activity areas, group instruction rooms, conference rooms, libraries, offices, speech clinics, offices used for educational purposes and music rooms for instruction, practice and performance., that would be sufficient. You have the choice to do either one or the other, or both Options. For example, if you had some core learning spaces that lent themselves to Option 1 (minimum NRC) and you had another handful of classrooms that lent themselves to Option 2 (calculations) you could use both options to meet the criteria.

Hi Eri

Unfortunately, it's not as easy as being able to count the cloud areas twice.

There is an increased performance benefit, but you will need to calculate the reverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) time of the space to meet the LEED requirement that way, instead of going the square footage of treatment route.

What will happen with the clouds is that the absorption coefficients behind the NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. value will increase. The only way to appropriately represent this is by calculating reverb time using the improved absorption coefficients.

So, would it be enough to use the ANSI calculation path, where I measure the space volume and include the absorption coefficient of different materials at 500, 1000 & 2000 Hz? ...Can in this case count the ceiling cloud area twice? that is the only way I can achieve .6 or less.
I don't know if I am missing something or is there another type reverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) time calculation that I should do.

You would use the ANSI calculation path, but you would use improved/revised absorption coefficients for the panels to take into account the open sides of the clouds. These would need to come from the manufacturer or estimated based on a similar product. Armstrong, for example, sells a cloud product called Soundscapes that uses their NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. 0.9 ceiling tile and publishes acoustic data.

Doubling the panel area would not be the correct way to do the calculation.

Daniel,

It seems it is getting more complicated than I originally thought. We may need to hire an acoustical consultant to perform this calculation, as I am a simple architect.

Thanks for your help.

Hi David:

The LEED requirements are only concerned with background noise caused by HVAC equipment. It sounds like you already know how to do this for the duct layouts. To calculate noise levels that might be in an adjacent room, select "Elements", "Sound Transmission", and then "Equipment Room Wall". To calculate equipment noise levels from equipment that might be above a ceiling you would select "Ceiling system" instead of "Equipment Room Wall".

Exterior noise from non-HVAC items (traffic, etc.) is covered in the ANSI standard but not a requirement by LEED.

Does that answer all your questions?

Hi Rebecca

I think the path you are on is good. The gymnasium is not a core learning space for acoustics but is one for daylight, views, and thermal comfort.

Maura, I don't know anything about the calculations behind this form, but it strikes me as likely that the Beta form had a bug that was resolved in the updates up to v4.0. Is the change in results creating compliance questions?

Yes, it is. The reverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) values go up significantly in v4.0.

Before upgrading forms, I have found it very helpful to access the Form Fix Log (available for download from this page - http://www.usgbc.org/DisplayPage.aspx?CMSPageID=1447 and from main landing page of LOv3 (Form Updates)) to understand the reasons for the changes to the forms. For instance, IEQp3's v3.0 update of the form states: "Corrected calculation error in ANSI ReverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) Time table; revised NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. and ANSI tables to allow documentation of non-rectangular rooms."

That should be fine to use to determine outdoor noise levels on the school site.

For indoor noise levels from HVAC, you will need to calculate those based on equipment selections and duct layouts.

I downloaded it from the Acoustical Society of America (http://asastore.aip.org) in 2007 but the 2002 version does not appear to be available anymore. They only have 2009 and 2010 versions.

Consider using this contact information from Armstrong's website who provided it along with Trane at no cost(http://www.armstrong.com/commceilingsna/article21193.html) to contact ASA: “These standards and many other national and international standards can be obtained in PDF format from the Acoustical Society of America Online Store at: http://asa.aip.org. Standards may also be ordered by fax or mail from: Acoustical Society of America, 35 Pinelawn Road, Suite 114E, Melville NY 11747-3177, Phone: 631-390-0215, Fax: 631-390-0217, Email: asastds@aip.org.” You might mention to them that folks are still using this and it would be great to still have available.

my email is carolina@natexarchitects.com

Your emailing that would be fantatic! Thanks for your help!
My question is why doesn't USGBC have it if they require us to use it. It is not right!

Carolina –

You must be new to the LEED game. There are extensive standards and references that USGBC does not provide and most of those require payment. It was great that Armstrong and Trane provided the ANSI resource as a free download via ASA.

Carolina –

I contacted ASA on your behalf and got a copy of the 2002 standard for you, which I have e-mailed to you.

As an FYI, here is the information I got from ASA when I asked that they post the 2002 document back to the ASA website:

“Pursuant to your request, since we cannot post the obsolete document you are requesting, the Standards Manager, Susan Blaeser, asked me to send you the attached complimentary copy of the Obsolete document ANSI S12.60-2002 (R2009) for your use. As noted in the attached PDF, the document is OBSOLETE and MAY NOT be referred to as an American National Standard. It is provided for historical purposes only.

As you saw on the website, the document has been replaced by two parts: ANSI/ASA S12.60-2010/Part 1 American National Standard Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools, Part 1: Permanent Schools and ANSI/ASA S12.60-2009/Part 2 American National Standard Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools, Part 2: Relocatable Classroom Factors.”

Hi Jessica:

If each workshop area had a dedicated classroom, I think you would have a pretty good argument that the workshop areas are ancillary, areas only used for students to work on their projects. On the flipside, I recently had a project where the workshops did not have dedicated classrooms and we elected to call them core learning spacesCore learning spaces are spaces for educational activities where the primary functions are teaching and learning and where good speech communication is critical to a student's academic achievement. These spaces include, but are not limited to, classrooms, enclosed or open plan), instructional pods or activity areas, group instruction rooms, conference rooms, libraries, offices, speech clinics, offices used for educational purposes and music rooms for instruction, practice and performance. because some instruction would occur in the workshop.

Thanks a lot Daniel! I greatly appreciate your prompt response. I will let you know if we have any problems with that interpretation or if we find any other information on this.
Thank you!

I was wondering if this approach had been succesful? I have a project with a similar situation and I wanted to go this route if it was accepted by GBCI.

Hi Renee:

The formatting didn't quite come through, but it looks like you're filling out the form correctly. Did you also upload the spec sheets for the ceiling tile and wall panels that indicate that the materials have an NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. 0.7? The form won't say that it's completed until you do that as well.

If that still doesn't work, I would just check the box at the end of the form under "Special Circumstances" and explain the situation. Through various stages of upgrades and LEED revisions, I've had more than one time where a form didn't work for me and I had to explain what was wrong with it.

Renee -

I was going to suggest that you ensure you have the most recent version of the Form. There is a v4.0 of the form for this prerequisite per the LOv3 Form Fix Log (https://www.usgbc.org/ShowFile.aspx?DocumentID=9144). The form version is listed in the lower right corner of the form. That might be part of the problem.

You can ask your Project Administrator to update the Form by contacting USGBC.

Note: LOv3 Help says: "What if problems continue with the form?

USGBC encourages all customers to use the Feedback link (see Feedback Form for guidance) for any issues encountered when trying to complete a form. All issues are reviewed, handled on a case-by-case basis, and rolled into future form versions as necessary. Regardless of the issue, a member of our team will follow-up with you directly."

It depends on what approach you want to take in the templates.

If you're going for the "all ceiling area = NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. 0.7 or better approach", then you would need to add panels. If you are willing to make RTReverberation time (RT) is a measure of the amount of reverberation in a space and equal to the time required for the level of a steady sound to decay by 60 dB after the sound has stopped. The decay rate depends on the amount of sound absorption in a room, the room geometry, and the frequency of the sound. RT is expressed in seconds. (ANSI S12.60–2002) calculations instead, you can make the calculation and you may, or may not, need to add more panels depending on the results.

If the space is greater than 20,000 cu. ft., however, the RT caluclation is your only option.

Hi Renee:

I don't think I can help you with this but I'll try to find someone who can. I'm only up on the acoustics requirements...not the submission processes.

Either way would probably work - You could wait until the Construction Phase and submit the final cutsheets, or you could try submitting what documentation you have for the design review.

In this case, you would probably submit the project specifications that clearly state the minimum performance requirements for the various materials, provide cutsheets from the three approved manufacturers to show several product options that meet the requirements, and provide the calculations that meet the requirements using those products.

You may still be asked to defer the credit until construction review, but at least you've had the opportunity to see if there are any other issues raised by the review that you might still have time to correct.

Hi Rodrigo:

I think you could make the case that these are not HVAC equipment and can be excluded if you can turn them off when they are not needed. My interpretation of LEED's explaination of "HVAC equipment" is equipment used for indoor 'climate control', and not specialty exhaust equipment. If they were designed to be on all the time, however, you might be able to make an argument that they need to be included.

Hi Brian:

I completely agree. I have not heard of any other compliance approaches, however, that satisfy LEED's understanding of "core learning space" and a musician's actual needs. I hope you bring it to their attention, though! Keep us posted.

Hi Brian:

I can't find in any of my templates where it says "0.6 seconds or less". All of the ones I've worked on, and the current credit requirements, say that the reverb time needs to meet the ANSI standard. It's possible that it's a new revision and a typo.

If you want a definitive answer, I would ask for clarification. I, personally, would follow the ANSI standard (as that is the original basis for the LEED requirements) and then explain what I did in the comment box.

Sorry, I've just checked the data sheet properly. On the data sheet for the acoustic panels it states that when the gap between hard ceiling to bottom of panel is 125 mm (yes) and the insulation is 60 mm (yes), then the NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. is 0.95. I also now under stand that the 20000 cf criteria is per room, not entire facility. that means I could use case 1, option 2. to prove my case. I just need to area weight the NRC value. for that i need a good assumption of the NRC for the normal ceiling tiles with the same ceiling depth and insulation dimensions...any ideas?

Woops! Just got the real value for the NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. of the normal tiles from the manufacturer...0.05. Ouch!

If the NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. compliant area does not cover the ceiling area for spaces < 20,000 cf, can one try with calculations which include walls, floors, windows, etc. to prove RTReverberation time (RT) is a measure of the amount of reverberation in a space and equal to the time required for the level of a steady sound to decay by 60 dB after the sound has stopped. The decay rate depends on the amount of sound absorption in a room, the room geometry, and the frequency of the sound. RT is expressed in seconds. (ANSI S12.60–2002) are compliant?

Yes, you can with ANSI S12.60-2002.

Hi Jean:

Sorry for the late response.

Yes, you can do individual calculations for reverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) time in each space instead of designing the ceiling area square footage of NRCNoise reduction coefficient (NRC) is the arithmetic average of absorption coefficients at 250, 500, 1,000, and 2,000 Hz for a material. The NRC is often published by manufacturers in product specifications, particularly for acoustical ceiling tiles and acoustical wall panels. 0.7.

I would do a calculation for each space unless they are identical.

Hi Keelan:

This response is very deliquent (sorry about that).

Fill out the STCSound transmission class (STC) is a single-number rating for the acoustic attenuation of airborne sound passing through a partition or other building element, such as a wall, roof, or door, as measured in an acoustical testing laboratory according to accepted industry practice. A higher STC rating provides more sound attenuation through a partition. (ANSI S12.60–2002) tables as complete as possible. Make sure to include roof, floor/ceiling, and exterior wall assemblies. I'm not sure why the template doesn't show the point documented.

A library is considered a core learning space, so treat the floor/ceiling adjacency as a learning space to learning space situation.

If the library (being a core learning space) is greater than 20,000 cu. ft. the reverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) time would need to be 1.5 seconds or less. You can use the RTReverberation time (RT) is a measure of the amount of reverberation in a space and equal to the time required for the level of a steady sound to decay by 60 dB after the sound has stopped. The decay rate depends on the amount of sound absorption in a room, the room geometry, and the frequency of the sound. RT is expressed in seconds. (ANSI S12.60–2002) calculation spreadsheet in the template to calculate this.

Sorry again for the delayed response. For some reason I've stopped receiving notification of questions.

Unfortunately, placing acoustic panels in the room probably won't reduce the noise levels from the mechanical equipment to any significant degree if the spaces are already meeting the reverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) time requirements. If it were a highly reverberant room, it might be a little different, but it probably won't do anything for you in this case.

One option that might work would be to hang panels around the unit, making it semi-enclosed. You would need to work with the mechanical engineer to make sure that this wouldn't cause a problem for air flow or heating/cooling, however.

Also, I would try to work with the mechanical contractor or the manufacturer to see what can be done to reduce the noise levels of the installed evaporators. Maybe retrofitting spring or rubber isolators on the fans or reducing the speed that they operate at.

Lastly, I would also make sure that the noise levels were measured correctly. You're only 2 dB(A) off from the requirement. So close! Subjectively, this small of a difference would probably not be noticeable but LEED will probably stick to the 45 dB(A) requirement.

Good luck!

Daniel,
Thank you for your answer and solutions. Our team will have to evaluate deeply this case!

The STCSound transmission class (STC) is a single-number rating for the acoustic attenuation of airborne sound passing through a partition or other building element, such as a wall, roof, or door, as measured in an acoustical testing laboratory according to accepted industry practice. A higher STC rating provides more sound attenuation through a partition. (ANSI S12.60–2002) requirements you are referring to are in the Enhanced Acoustics credit IEQc9 in LEED for Schools 2009, not the prerequisite. These requirements were moved to the enhanced credit in the 2009 version to allow for open plan classrooms and other owner requested situations you are describing and still meet the prereq.

It sounds like you could meet the prerequisite requirements by designing for ReverberationReverberation is an acoustical phenomenon that occurs when sound persists in an enclosed space because of its repeated reflection or scattering on the enclosing surfaces or objects within the space. (ANSI S12.60–2002) Time and HVAC Background Noise but not the IEQc9 enhanced acoustics credit.

Thanks very much for your feedback and clarfiication Daniel. Re-reading the credit I see that I did indeed misread it and think I have a better handle on it now!