Good IAQIndoor air quality: The quality and attributes of indoor air affecting the health and comfort building occupants. IAQ encompasses available fresh air, contaminant levels, acoustics and noise levels, lighting quality, and other factors. and comfort begin with proper design and construction techniques, and continue through effective operations and maintenance. Exposure to mold and bacteria can cause allergic reactions and general health problems, ruin building materials, and create unpleasant odors. Even if you decide not to pursue this credit, taking steps to prevent mold is a really good idea.
This can be an easy credit to achieve, but it takes a lot of coordination among the design team, contractors and subcontractors, and the school’s operations staff. To achieve IEQc10, projects first have to achieve the following credits, which contain key steps that will contribute to your overall success with preventing mold:
Start by verifying that each of the three required credits can and will be achieved by your project.
In addition, you must control and limit relative humidity during occupied and unoccupied hours to at or below 60%. That means that you’ll need mechanical equipment that can regulate humidity, and it must have appropriate set points.
Note that because of the construction-related aspects of these credits, IEQc10 is a construction-phase credit, even though it was listed on some LEED checklists as a design-phase credit.
You also have to develop an IAQ management plan for the ongoing prevention of mold and indoor air quality problems. The IAQ plan has to be based on the US EPA’s “Building Air Quality: A Guide for Building Owners and Facility Managers.”
Developing your IAQ management plan can prevent mold problems from getting out of hand. Photo – Phillip Fry, www.moldinspector.comAlthough the credit’s primary intent is to prevent mold growth, the IAQ management plan will need to address more than just mold-related problems. When writing your IAQ plan, pay close attention to Section 4: Developing an IAQ Profile and Developing an IAQ Management Plan in Section 5 of the EPA document.
Since IEQc3.1, a LEED construction phase submittal, has to be achieved before a project can be approved for this credit, don’t bother to submit IEQc10 until the LEED construction submittal. This does not mean that you should hold off until after design to plan for achieving this credit, however!
In general, your IAQ plan should cover the following items:
An IAQ plan can be created by the contractor, architect, mechanical engineer, facilities manager, or owner; however, ideally it is a collaboration of as many of these parties as possible.
The fact that you must earn three other IEQ credits prior to this one does not mean your project team should defer addressing IEQc10 early in the project. You need to confirm that your project can comply right at the outset. And, even if your project is not able to attain the other three IEQ credits, following a mold prevention plan is in your project’s and the students’ best interests.
Hot, humid climates, are especially susceptible to mold problems because they offer lots of opportunities for condensation and poor drying conditions. Pay special attention to air-sealing, adequate dehumidification, and good wall, roof, and foundation details to prevent leaks. Also, watch out for “over cooling” which can drop surface temperatures below the dew point. Focus on areas in contact with the earth and equipment with condensate pans and drip tubes. Also, regularly wetting of the exterior surfaces of buildings with poorly designed, poorly aimed, irrigation systems can be problematic.
In all climates, even dry ones, mold growth can easily occur, especially in building areas with kitchens, bathrooms, laundry facilities, and swimming pools. Air-conditioning is common in almost all parts of North America in some seasons, and is often associated with mold problems due to the potential for condensation on cold surfaces, from humid outside air.
This 150x micrograph shows mold on carpeting—a potential hazard to occupant health. Photo – Jeff May
Mold needs food, oxygen and moisture in any form. Food (in the form of dust) and oxygen are everywhere, so the only ingredient you can really control is moisture. Buildings are susceptible to mold growth from flooding, humidity conditions that exceed surface dew point temperatures and leaks, which can be from both rain and from plumbing. Absorptive building materials such as drywall, wood, insulation, and carpet, which provide a food source for mold are especially susceptible to mold growth.
Reducing or eliminating moisture is the key to a successful mold prevention plan. This credit requires controlling humidity, because high humidity leads to condensation on cool surfaces and keeps wet things from drying out. But keeping bulk moisture (from rain, sprinklers, or melting snow) from getting into the building is at least as important. Air sealing and flashing details are key to controlled bulk moisture intrusion, and wall assemblies have to be designed carefully so that any water that does get in can dry out.
It helps to hire and work with design, construction, and operation teams with knowledge of and experience with IAQ issues and mold prevention. A team approach is important because these topics encompass everything from HVAC design to building envelope design and construction, materials selection, protection of materials during construction, HVAC controls and set points, and regular inspections during building operations.
Discuss the importance of mold prevention and IAQIndoor air quality: The quality and attributes of indoor air affecting the health and comfort building occupants. IAQ encompasses available fresh air, contaminant levels, acoustics and noise levels, lighting quality, and other factors. management with the project team and operations staff. Efficient coordination between the project team and the operations staff is ideal, when planning ongoing IAQ management. When determining the probability of achieving IEQc10 discuss the following items.
All three of the following credits must be achieved before your project can achieve IEQc10. None of them is particularly hard, or presents major obstacles.
The IAQ plan is the portion of the credit that focuses on building operation and maintenance. It should include:
Implementing the IAQ plan is easy for most projects, especially if the operations staff is included in the process of writing the plan. See the Documentation Toolkit for guidance on the IAQ Management Plan for Mold Prevention.
For a more comprehensive IAQ plan, you may want to include design recommendations for the architect and mechanical engineer, steps for preventing moisture buildup during construction, and for remediation if building materials become wet or moldy during construction. These steps are not required for the credit, though.
Accountability is another key element to mold prevention and ongoing IAQ maintenance. Subcontractors should be contractually required to implement relevant parts of the credit requirements—meeting IEQc3.1: Construction IAQ Management Plan—During Construction, and appropriate sequencing of construction activities. The operations and maintenance personnel should also be contractually required or directed to implement the IAQ plan based on the EPA document.
Since IEQc3.1, a LEED construction phase submittal has to be achieved before a project can be approved for this credit, don’t bother to submit IEQc10 until the LEED construction submittal. This does not mean that you should hold off until after design to plan for achieving this credit, however!
Keep costs low by starting early in the design stage and by understanding building science - how to keep moisture out of the building and air stream, and how to manage humidity levels through HVAC design.
Following best management practices for mold-control should limit liability exposure for the project team and school district, but be very careful (and consult with a lawyer) before saying or doing anything that could be construed as a guarantee that there will be no mold.
You can earn an Exemplary Performance point for this credit through IDc1. There are not specific benchmarks for how to earn the point, but consider some of the following options:
The HVAC system must be able to limit interior relative humidity (RH) to 60% or below during all hours, occupied and unoccupied.
Some projects already have to limit their RH to 60% or below to meet the requirements of ASHRAE-55 for IEQc7.1. However, ASHRAE-55 has a larger window of acceptable RH levels, and the levels vary depending on temperature and air speed. IEQc10 does not provide the flexibility that ASHRAE-55 does. All projects irrespective of temperature and air speed, must limit RH to 60% or below. ASHRAE-55 also focuses on occupant comfort and does not address unoccupied spaces and times. IEQc10, however, demands that humidity is controlled at all times. Meeting these requirements may require dehumidification in many regions.
You’ll need to implement an ongoing IAQ plan based on the U.S. Environmental Protection Agency (EPA) document, Building Air Quality: A Guide for Building Owners and Facility Managers, EPA reference number 402-F-91-102, December 1991 (see Resources). This document is long (over 200 pages!) and covers the general IAQ issues in addition to mold that you’ll need to address for your IAQ plan. See the Documentation Toolkit for the IAQ Management Plan Guidelines, which gives specific guidance on sections of the EPA document to pay close attention to.
Review the U.S. Environmental Protection Agency (EPA) document, Building Air Quality: A Guide for Building Owners and Facility Managers (see Resources). The IAQ plan will be based on this document.
Draft the IEQc10 plan for ongoing IAQ management, and arrange for it to be implemented. The plan should include project goals and scope of IAQ management, an outline of regular building and HVAC inspections, ongoing strategies and maintenance for the prevention of moisture and mold during operations of the building, remediation strategies if mold or other air quality issues are detected, and it should clearly identify who is responsible for implementing each plan component.
Identify an IAQ manager who will coordinate activities to minimize the impact of IAQ-problems. This person’s job might include responsibilities such as:
Consider including the following in the IAQ plan: design recommendations for the architect and mechanical engineer, steps for preventing moisture buildup during construction, and plans for remediation if building materials become wet or moldy.
Consider the following when writing your plan for ongoing IAQ management and designing for mold and moisture management:
Determine which building spaces could be prone to high levels of humidity and moisture, such as restrooms, kitchens, locker rooms, indoor and outdoor swimming areas, and the basement or crawlspace. Pay close attention to the design, product selection, and ventilation of these spaces. Include a section in the IAQ management plan about regular inspection and maintenance in these locations.
Microbiological growth within the HVAC system, duct work, drain pans, and air filters can go undetected for long periods, spread throughout the building, and cause serious illness or death (for example, through Legionnaire’s disease). When designing these systems, provide for easy access for inspection, cleaning, draining, and replacement in these areas.
Areas that are prone to high levels of moisture need to be adequately addressed during the design stage. Consider design techniques such as adding ventilation, air-sealing, adding insulation at areas of thermal bridging, installing highly insulated windows, and selecting mold-resistant materials.
Consider installing relative humidity meters to verify that it is being controlled.
Provide both designers and contractors with a mold training session, or at least literature on mold awareness and prevention.
Determine which building systems are most susceptible to mold growth and IAQ-related problems, and be sure to address them properly in the IAQ management plan. These systems may include the HVAC, roof, wall, and ceiling assemblies, plumbing systems, as well as the foundation walls.
Remember that the IAQ management plan focuses on operations, but a good design will minimize the risk of mold. When designing roof and wall systems, include detailed drawings of drainage planes and flashing installation, and specify appropriate joint sealant.
Determine if your project will need to incorporate a dehumidification system in the HVAC design to limit RH to 60% or below.
Identify the IAQ features of the HVAC design such as the dehumidification and controls that can be incorporated into building commissioning for EAp1 and EAc3.
Verify that credits IEQc3.1: Construction IAQ Management Plan—During Construction, IEQc7.1: Thermal Comfort—Design, and IEQc7.2: Thermal Comfort—Verification are being planned for and attempted.
Design the HVAC system to limit relative humidity (RH) to 60% or lower during both occupied and unoccupied load conditions. Be sure that your HVAC design and controls meet both ASHRAE 55 and the RH requirements of IEQc10.
You are required control RH during unoccupied hours, such as summertime, because any inactive times where RH might not be controlled, allows for mold buildup in the HVAC system and duct work.
Make sure that all equipment that might collect or generate moisture is located and installed for easy access for inspection and cleaning.
Design the building to avoid infiltration of air and water, and to avoid trapping moisture. Use material assemblies that are not susceptible to mold growth. See LEEDuser’s strategy on air barriers for tips on design and construction with these goals in mind.
When designing the building, remember that in the presence of oxygen or moisture, mold can grow on any organic material—wood, paper, drywall or insulation. This does not mean you must avoid using these materials, but you should pay close attention to these areas. For example, if you install vinyl wallpaper, a vapor barrier, you are trapping moisture beneath the wallpaper, which may cause mold that cannot be seen.
Remember that any material can collect dust and thus provide a medium for mold growth, so keep both dust and moisture away from all materials as much as possible.
Avoid using carpet near entryways or areas where water and dirt may be tracked into the building. Installing permanent entryways helps to limit the amount of moisture that gets into the building and can contribute to earning IEQc5: Indoor Chemical and Pollutant Source Control.
Finalize the IAQ management plan. Verify that the plan addresses the issues outline in the U.S. Environmental Protection Agency (EPA) document, Building Air Quality: A Guide for Building Owners and Facility Managers.
Hold an orientation meeting with the contractor to review all LEED-specific issues, such as the IAQ management plan during construction, mold prevention, and product purchasing. A separate meeting with the subcontractors should orient them to responsibilities related specifically to their trades.
Check that drainage planes and flashing details are all well-developed and documented, especially around openings and at transition points.
If you leave flashing details for the construction crew to figure out onsite, don’t expect best moisture management practices to be carried out.
Enabling coordination and early communication among the general contractor, the subcontractors, and the design team can minimize scheduling delays as well as push-back from subcontractors.
Include the requirements of mold prevention and IEQc3.1 in construction specifications.
In the construction documents, include the major components of mold prevention that need to occur during construction. These include meeting the SMACNA guidelines (part of IEQc3.1), protection of absorptive materials, waiting to install absorptive or organic materials until the building is enclosed, providing drainage, cleaning duct work before installation, and keeping relative humidity below 60% after the building has been enclosed.
Sequence building construction to minimize the exposure of organic materials such as plywood and framing lumber to moisture and weather. Be sure to enclose the building envelope as soon as practicable, and inspect for proper weather and water proofing.
Developing a checklist for weekly mold prevention activities during construction and related to-do’s is a convenient way to stay on top of required tasks. This list can be used at weekly meetings as well as posted around the site.
Provide clear construction drawings, specifications, commissioning reports and operations manuals so that operations staff can refer to them during building operations.
The GC reviews the IAQ management plan with subcontractors during regular construction meetings to ensure that plan measures are being followed and use the checklist developed during construction documents.
Implement the construction-related components of the IAQ management plan, and ensure that correct procedures are being followed throughout construction.
Conduct periodic inspections for moisture buildup, standing water, and improper storage of absorptive materials. These activities are consistent with implementation of IEQc3.1.
Writing good housekeeping into your plan helps to prevent the growth and spread of mold. Following the IAQ management plan can prevent additional costs due to moisture issues such as replacing materials due to moisture damage.
Commission building systems, including the HVAC system, dehumidification system, and verify proper control set points.
Implement the ongoing IAQ plan during building operations and maintenance.
Conduct regular building walkthroughs to monitor airflow, temperature, humidity, odor, and other IAQ problems. It is a good idea to do a walkthrough with project drawings to take note of locations with issues.
Identify an IAQ manager to hold responsibility of the building IAQ. They will conduct and review the IAQ profile, track IAQ-related documents and records, and monitor general facility operation and maintenance, housekeeping, pest control, and renovations and remodels. It is important to clearly define their responsibilities.
Verify that HVAC set points are properly adjusted to limit RH at or below 60%. Make sure the operations staff understands the importance of the given set points.
Train the operations staff to identify and respond to any IAQ issues that may arise. It is helpful to educate teachers to immediately alert the maintenance staff to any areas of water intrusion or IAQ problems.
Conduct the thermal comfort survey in compliance with IEQc7.2: Thermal Comfort—Verification and log complaints. Determine if corrective action measures are required.
If any mold is found, determine the cause of moisture or mold and see if you can fix the moisture source. You might need to provide additional dehumidification or ventilation along with cleaning the contaminated area. For mold where the cause cannot be determined or is persistent, retain an industrial hygienist, toxicologist or a building science expert to identify the risks and perform any necessary remediation. Remediation efforts can be as extreme as removing walls, ceiling, and floors. It is best to address mold before it gets to such an extreme level of contamination. After fixing the source of the problem and cleaning or remediating the mold, perform periodic inspections to verify no reoccurrence of mold.
During occupancy, watch for visible signs of mold growth and musky odors, signs of moisture damage or discoloration, and locate the source. On a regular basis:
Develop an IAQ profile that describes the building structure, function, and occupancy features that impact IAQ. The profile should give building operators a better understanding of the current status of air quality in the building and baseline information on factors that have a potential for causing problems in the future. As part of the IAQ profile you will log complaints, collect HVAC system data, understand set points and operations controls, and conduct regular building walkthroughs to look for areas of potential IAQ problems.
Collect and keep on file HVAC operations manuals and repair records, IAQ complaints, MSDS for cleaning supplies, and pest control chemical information.
Designing and operating a building to minimize mold exposure has the potential to reduce student and teacher absentee rates due to mold-related illnesses.
Depending on the extent of the mold found, remediation techniques can be expensive. Preventive strategies of the ongoing IAQ management plan will reduce the likelihood of going to extreme measures to remove mold.
Excerpted from LEED 2009 for Schools New Construction and Major Renovations
To reduce the potential presence of mold in schools through preventive design and construction measures.
Project teams must achieve the following credits:
Provide heating, ventilating and air conditioning (HVAC) systems and controls designed to limit space relative
humidity to 60% or less during all load conditions, both occupied and unoccupied.
Develop and implement on an ongoing basis an IAQIndoor air quality: The quality and attributes of indoor air affecting the health and comfort building occupants. IAQ encompasses available fresh air, contaminant levels, acoustics and noise levels, lighting quality, and other factors. management program for buildings based on the U.S.
Environmental Protection Agency (EPA) document, Building Air Quality: A Guide for Building Owners and Facility
Managers, EPA reference number 402-F-91-102, December 1991.
A complete guide to preventing mold and reducing the probability of it recurring can be found in the EPA’s Mold Remediation in Schools and Commercial Buildings, EPA reference number 402-K-01-001. The GREENGUARD Environmental Institute offers its GREENGUARD Mold Protection Program™. The EPA Design Tools for Schools offers a comprehensive program for preventing mold during the design and construction phases of a school project. These documents contain a comprehensive overview of the principles and practices stated here and serve as valuable resources in constructing commissioning plans and operation and maintenance guides.
Project teams should be aware of potential differences in construction if portable classrooms and modular classroom units are being used.
This is the referenced standard for writing the mold prevention plan.
Provides guidelines and links to help in preventing moisture.
This website is dedicated to the remediation of mold.
This website describes how to use a psychometric chart.
This website provides articles, resources, videos and other information.
This website provides information such as a Best Practices Manual, assessment tools, technical resources, and training and events.
This website includes products, certification programs, and resources.
The template provided here gives a structure for developing an Indoor Air Quality (IAQIndoor air quality: The quality and attributes of indoor air affecting the health and comfort building occupants. IAQ encompasses available fresh air, contaminant levels, acoustics and noise levels, lighting quality, and other factors.) Management Plan compliant with the requirements of IEQ Credit 10: Mold Prevention.
The following links take you to the public, informational versions of the dynamic LEED Online forms for each Schools-2009 IEQ credit. You'll need to fill out the live versions of these forms on LEED Online for each credit you hope to earn.
Version 4 forms (newest):
Version 3 forms:
These links are posted by LEEDuser with USGBC's permission. USGBC has certain usage restrictions for these forms; for more information, visit LEED Online and click "Sample Forms Download."
Documentation for this credit can be part of a Design Phase submittal.
Do we need humidity control on every single heat pumpA type of heating and/or cooling equipment that draws heat into a building from outside and, during the cooling season, ejects heat from the building to the outside. Heat pumps are vapor-compression refrigeration systems whose indoor/outdoor coils are used reversibly as condensers or evaporators, depending on the need for heating or cooling. In the 2003 CBECS, specific information was collected on whether the heat pump system was a packaged unit, residential-type split system, or individual room heat pump, and whether the heat pump was air source, ground source, or water source. that is in the builidng? We are using ERV's throughout the project but don't know exactly what other equiptment and/or what cost premium may be part of this credit.
Naten, the credit requirements are not as specific as requiring humidity control on very heat pumpA type of heating and/or cooling equipment that draws heat into a building from outside and, during the cooling season, ejects heat from the building to the outside. Heat pumps are vapor-compression refrigeration systems whose indoor/outdoor coils are used reversibly as condensers or evaporators, depending on the need for heating or cooling. In the 2003 CBECS, specific information was collected on whether the heat pump system was a packaged unit, residential-type split system, or individual room heat pump, and whether the heat pump was air source, ground source, or water source.. However, you do have to provide humidity control somehow, to limit RH, per the credit requirements. I would work with your mechanical engineer on what this might entail.
Has anyone actually made "a plan" for this credit? based on the I-BEAM or EPA document references, this document could be of incredible length, with charts, tables, complaint logs, etc. Has everyone done these plans as detailed as thosed referenced in the LEED guide?
I think our owner would freak out if we presented him with a 200-page document.
Sandra, have you checked out our plan template in the Doc Toolkit above? It's less than 200 pages ;)
I am in the process or completing IEQc10 credit form. The credit form lists a required upload as "Upload IEQ10c10-1. Provide humidity calculations at peak conditions, both occupied and unoccupied." I do not understand what a "humidity calculation" is. Is a narrative describing how the HVAC system was designed to address humidity control during occupied and unoccupied periods acceptable??
James, I think that since the previous field in the form is a narrative, GBCI is looking for something more along the lines of engineered numbers or calculations.
My engineer is asking for help with these calculations. He says that he has no idea what they want. Any guidance I can provide him would be helpful.
My load calculation/ energy simulation software provides a "Building Humidity Profile" output that lists the maximum relative humidity in every space, at both occupied and unoccupied times. I use Trace 700, but I'm sure other programs have a similar output.
We often design UV lights to sterilize intake air in an effort reduce mold growth. Is this an acceptable strategy for achieving this credit? Is it worthy of an ID credit?
Either way; what is the best way to document compliance? Thanks.
Beckham, this could definitely be a part of a strategy for achieving this credit, but it's not close to being sufficient in itself. There are a number of specific requirements to meet—see our guidance above.
I would say that this would not qualify for an ID credit, because it's already covered under this credit.
Tristan, Can I use this Credit as an ID for a C&S project? Thanks!
Sonia, I would say that this is a bit tricky, because one of the IEQc10 requirements is to earn IEQc7.2, but that credit does not exist in CS, because comfort verification would not usually be in the scope of a CS project.
I think if you can show somehow that you can meet the intent of IEQc7.2, and meet all the other requirements here, then there is a reasonable case to make this an ID credit. I would get your approach verified through a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide before proceeding, given the effort involved.
Tristan, Indeed the Thermal Comfort Survey would not be feasible but the landlord wants to reduce his O&M costs and is willing to add UV filters and IAQIndoor air quality: The quality and attributes of indoor air affecting the health and comfort building occupants. IAQ encompasses available fresh air, contaminant levels, acoustics and noise levels, lighting quality, and other factors. Management Plan language in the contract with its tenants. Will give it a thorough thought and proceed with a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide if needed.... Will keep everyone posted on the outcome.
Someone already wrote a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide regarding UV lights on AHUs as an Innovation Credit a few years ago for NC (it may have been for a 2.2 project). You can look that up at the USGBC site but the result was the UV lights needed to be part of a whole strategy to prevent mold and providing clean air. This credit may be a good outline for a successful CIR approach for a CS project.
Thanks Susan! Will check and let everyone know!
Hi all. I checked the LEED Interpretations and Addenda Database regarding UV Lights / Filters and Mold prevention and did not find the CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide mentioned previously (See http://www.leeduser.com/topic/uv-lights-id-credit). Does someone know or can send me the number? I would like to see if it is applicable to C&S V.2009. (The other 2 rulings that are somehow related with mold issues are #2302 and 5146 that are applicable for the C&S rating system.....).
Interpretation #695 might be of interest—I'm not sure.
Tristan, So far there are three (3) LEED Interpretations related to this issue: 695, 5146 and 2302. Will see how the owner wants to proceed and will inform all regarding the outcome.
I am wondering if anyone has experience with this credit, and where the RH sensors are required. We typically integrate them with the thermostat, however, we do not have a thermostat in every room. So i'm unsure on how other people are verifying the relative humidity in all spaces without literally putting a relative humidity sensor in all spaces, which can get rather expensive.
If you go back to NC v2.1 where this requirement originated, the requirement is to monitor by zone. That should be sufficient.
How could a school project gain an Innovation in Design point under this credit?
According to the LEED Reference Guide, you can earn a point here under IDc1, but there is no prescribed process for how to do that.
I doubt there is very much if any precedent here. I would start by asking what is driving your project to pursue this credit and why you think you might be eligible for an EP point?
Is it possible to achieve this credit with a naturally ventilated building located in northern California
Sure, there is nothing that would immediately rule that out. No. Cal. is a big place—is it a particularly wet area?
Are there any particular sticking points you're worried about?
You could argue that in a cool, wet climate, this credit is quite important to achieve.
My concern is the requirement "Provide heating, ventilating and air conditioning (HVAC) systems and controls designed to limit space relative humidity to 60% or less during all load conditions, both occupied and unoccupied." there is no language about exceptions for naturally ventilated buildings.
The relative humidity in CZ2 does not exceed 60%, which falls in the acceptable humidity standards for the credit. Our engineers have done a psychrometric analysis to support this assertion. So I guess my real question is: Are projects in climate zones that do not exceed 60% relative humidity exempt from requiring humidity controls?
I checked with Bob Kobet, our guest expert on this credit—so this is not an official GBCI response, but he's been pretty involved in this credit.
He said he'd never been asked this question, but in short, it seems like that should work, i.e., mechanical ventilation would not be required. His caveat was that the design should meet all the requirements embedded within ASHRAE 62, not only psychrometrics, but also calculations related to the effectiveness of ventilation distribution—stuff like are the spaces washed sufficiently, is the stack action strong enough, is the window-to-wall ratio sufficient? (Stuff that would be covered by IEQp1.)
A continuous air barrier can help prevent unwanted condensation and provide better and more efficient control over thermal comfort and humidity.
The Kobet Collaboraive
You must earn this credit to earn IEQc10.
Permanent entryway systems and MERV 13 filters can also help in the prevention of mold growth.
Do you know which LEED credits have the most LEED Interpretations and addenda, and which have none? The Missing Manual does. Check here first to see where you need to update yourself, and share the link with your team.
LEEDuser members get it free >
LEEDuser is produced by BuildingGreen, Inc., with YR&G authoring most of the original content. LEEDuser enjoys ongoing collaboration with USGBC. Read more about our team
Copyright 2013 – BuildingGreen, Inc.