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It’s about good IAQ for occupancy
The idea behind this credit is to ensure good 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.) for a project for occupancy. IEQc3.2 can be seen as a belt-and-suspenders credit: even if the IEQc4: Low-Emitting Materials credits are pursued, along with IEQc3.1: Construction IAQ Management—During Construction, IEQc3.2 ensures that the building ends up with the intended result. (Although it’s typical to do so, you don’t have to pursue any of those credits to go after this credit.)
The credit has a direct impact on occupant health and comfort, and it is often very important to the owner and occupants, that their new, LEED-certified building should smell “green” when they move in.
Flush out or testing?
The flush-out of indoor air required under Option 1 is frequently pursued by projects seeking a certain and predictable path.
Performing testing under Option 2 leaves open the possibility that despite all other efforts, the building could fail the tests, putting the credit in jeopardy.
You might wonder why, if a building earns the IEQc4 credits and IEQc3.1, there would be any chance of failing IAQ testing. For whatever reason, it happens. This might be due to VOC emissions from materials not covered by IEQc4, or from the undetected use of materials not meeting the spec.
Another reason for pursuing Option 1 is that the costs of IAQ testing are commonly greater than those of a building flush-out. Testing costs vary depending on the size of the building, the number of samples tested, and the travel and field work the testing agency needs to perform. Large buildings, or buildings with multiple independent HVAC systems, require more testing samples. One test is required for each separate ventilation system within the building, with not less than one sample per 25,000 ft2 of contiguous floor area.
On the other hand, the energy expenditure for flush-out under Option 1 can be large, and there may not been enough time after installation of finishes but prior to occupancy to conduct the flush-out. The tenant may also prefer the solid results of a test. All of these factors can push a project toward Option 2.
Two flush-out options
Under Option 1, you have two paths for performing the flush-out. Path 1 is performed prior to occupancy: provide 14,000 cubic feet of outdoor air per square foot of building space. Relative humidity must be maintained at 60% or below and temperature must be maintained at 60 degrees or above.
If there isn’t enough time prior to occupancy to follow Path 1, Path 2 allows you to reach the 14,000-cubic-foot threshold in phases. Path 2 requires an initial flush-out of 3,500 cubic feet per square foot, and then a daily flush-out that begins three hours before occupancy and continues until the end of occupancy for the day. During this period, a ventilation rate of 0.3 cfm per square foot must be maintained. This may be higher than the designed ventilation rate, so plan ahead for this.
Common pitfalls to avoid
This credit is typically easy to achieve if you plan ahead and avoid these common pitfalls:
- Early in the design of the mechanical systems, take into account the requirements for flush-out to ensure that the HVAC system is able to supply the required ventilation rate which is often higher than normal design conditions. Once the mechanical design is confirmed, the mechanical engineer should provide the contractor with the flush-out duration so that it can be worked into the construction schedule as soon as possible.
- If a flush-out is performed during very cold or very humid weather, maintaining minimum temperature and humidity levels may be impossible or require a lot of energy loss. Consider the testing path if these conditions are likely for your project.
- All permanent finishes have to be installed prior to flush-out. Also, all construction must be completed including punch-lists. Make sure that subcontractors are informed of the credit requirements and that all work is appropriately scheduled so as to not introduce contaminants after the flush-out.
- If you go for testing (Option 2) and fail, you can opt to do a flush-out and retest prior to occupancy, but your schedule needs to allow for it. Build in some schedule and budget contingency in case retesting is required.
Alternative approaches
In naturally ventilated buildings or other situations where using the HVAC is not possible or desired, alternatives such as temporary supply and exhaust fans placed in the windows are also possible. (Simply opening the windows is not enough, however.) Like natural ventilation in general, this approach works best for relatively dry, moderate climates where the temperature and humidity conditions required by the credit are easy to maintain.
If using fans, ensure correct placement of fans to provide an even flow of fresher outdoor air across each space, preventing short-circuiting. Check the EPA IAQ Design Tools for Schools Controlling Pollutants and Sources information on exhaust or spot ventilation practices during construction activity (although written for schools, it is applicable to any type of project). (See Section 5: Ventilation Techniques).
Consider these questions when approaching this credit
- Ask your mechanical engineer to run these preliminary calculations:
- Is the HVAC system capable of performing the ventilation rates required for flush-out?
- Can indoor temperature and humidity levels be maintained during the flush-out considering the scheduled season of the flush-out?
- What is the estimated duration of the flush-out under Path 1 and Path 2 and how will this affect the construction schedule?
- Important conversations that need to occur between the general contractor, building owner and occupants:
- When do occupants need to move in? Is the date flexible?
- Can the schedule allow time for a flush-out after construction completion and prior to occupancy? How much time is available?
- Will the project pursue a full flush-out (Option 1 – Path 1), or will occupancy occur during the flush-out (Option 1 – Path 2)?
- How will the basic requirements for having all finishes installed and construction complete be communicated to subcontractors?
- Things to consider when implementing IAQ testing:
- Does your building have multiple, separate ventilation systems?
- How many samples are required?
- Is your construction team confident that it can ensure contamination levels below credit limitations at the end of construction?
- Is there time at the end of the construction schedule to allow for flush-out and retesting if initial test results are above allowable levels for contaminants?
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How this credit is addressed in different building types
- A phased flush-out is possible if different sections of the building are completed at different times, which is common in multi-tenant or mixed-use project types.
- In facilities where air quality is particularly critical, such as healthcare and laboratory buildings, owners may require 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. testing as part of standard building practice.
- Buildings with large numbers of identical rooms with separate ventilation zones—such as hotel rooms or apartment units—have been allowed to perform random sampling as an alternative approach in situations when the delivery of outside air—on an air-change-per-hour basis—and the materials in a ventilation zone are identical. Project teams should confirm with GBCI that this is still applicable in LEED 2009.
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FAQs for IEQc3.2
Is it possible to combine Options 1 and 2 for different spaces in the same building?
This is not officially permitted in LEED. It might make sense in some projects, but teams should get 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 or LEED InterpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. in order to proceed.
Is it possible for the flush-out start date to vary by ventilation zone?
Yes. Areas served by completely separate ventilation systems—where air serving these spaces is not mixed with air serving any other spaces—can be flushed independently, as long as each such area is also isolated completely from all non-flushing areas per SMACNA guidelines.
Should a parking garage be included in a flush-out, if it is in a basement and not fully open to the outdoors?
No, parking garage space should not be included in this credit.
Do the outdoor air minimum quantities have to be met for each individual space, or for the building square footage as a whole?
Ideally, the flush out will be designed to provide the minimum volume to each individual space, and the LEED Reference Guide indicates that teams must take reasonable measures to ensure there is no obvious short-circuiting of the airflow. However, the requirements only address the "total air volume," so, for LEED credit compliance purposes it is only necessary to quantify the total outside air volume supplied to the entire building.
Do non-regularly occupied areas such as bathrooms and corridors have to be flushed-out?
Yes. All occupied gross floor areaGross floor area (based on ASHRAE definition) is the sum of the floor areas of the spaces within the building, including basements, mezzanine and intermediate‐floored tiers, and penthouses wi th headroom height of 7.5 ft (2.2 meters) or greater. Measurements m ust be taken from the exterior 39 faces of exterior walls OR from the centerline of walls separating buildings, OR (for LEED CI certifying spaces) from the centerline of walls separating spaces. Excludes non‐en closed (or non‐enclosable) roofed‐over areas such as exterior covered walkways, porches, terraces or steps, roof overhangs, and similar features. Excludes air shafts, pipe trenches, and chimneys. Excludes floor area dedicated to the parking and circulation of motor vehicles. ( Note that while excluded features may not be part of the gross floor area, and therefore technically not a part of the LEED project building, they may still be required to be a part of the overall LEED project and subject to MPRs, prerequisites, and credits.) (both non-regularly occupied and regularly occupied) must be included.
For LEED NC addition projects, do existing non-renovated areas need to be flushed-out or tested?
No, not if the project team is only certifying the addition, per se, as a separate LEED project. But the addition should be isolated from the existing, unrenovated areas in accordance with the SMACNA 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. Guidelines for Occupied Buildings under Construction.
Should we install furniture and furnishings before IAQ testing or flushout?
It's optional. In the past that has been unclear, and in an addendum issued 10/1/12, USGBC clarified that it is optional to install furniture and furnishings before IAQ testing or flushout for IEQc3.2. The word "optionally" has been inserted in the last paragraph of page 466 in the LEED BD&C reference guide, before "including furniture and furnishings."
For IAQ testing, how many sample points are necessary in non-mechanically ventilated spaces?
This is left to the discretion of the industrial hygienist or other qualified professional who is performing the testing and employing the EPA Standard.
Can testing be done over various days?
Yes, as long as it complies with the EPA standard.
I'm confused about the 11/1/2011 LEED addendum that removed the "1/25,000 SF or each contiguous area whichever is larger" language from the credit requirement. How do we determine the number of sampling locations for testing?
According to USGBC, the addendum was intended to give project teams more flexibility in testing locations. The 1/25,000 SF testing rate is still a good rule of thumb and is acceptable. USGBC is trusting that the project's industrial hygienist will have the best understanding of how to accurately test the spaces in the project. Select spaces to be tested so that each occupiable space type is adequately represented. Additional guidance can be found in the pilot prerequisite for performance-based IAQ.
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USGBC
Excerpted from LEED 2009 for New Construction and Major Renovations
IEQ Credit 3.2: Construction IAQ management plan - before occupancy
1 Point
Intent
To reduce 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.) problems resulting from construction or renovation to promote the comfort and well-being of construction workers and building occupants.
Requirements
Develop 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 plan and implement it after all finishes have been installed and the building has been completely cleaned before occupancy.
Option 1. Flush-out1
Path 1
After construction ends, prior to occupancy and with all interior finishes installed, install new filtration media and perform a building flush-out by supplying a total air volume of 14,000 cubic feet of outdoor air per square foot (4,500 cubic meters of outdoor air per square meter) of floor area while maintaining an internal temperature of at least 60° F (15° C) and relative humidity no higher than 60%.
OR
Path 2
If occupancy is desired prior to completion of the flush-out, the space may be occupied following delivery of a minimum of 3,500 cubic feet of outdoor air per square foot (1,000 cubic meters of outdoor air per square meter) of floor area. Once the space is occupied, it must be ventilated at a minimum rate of 0.30 cubic feet per minute (cfm) per square foot (0.1 cubic meters per minute per square meter) of outside air or the design minimum outside air rate determined in IEQ Prerequisite 1: Minimum Indoor Air Quality Performance, whichever is greater. During each day of the flush-out period, ventilation must begin a minimum of 3 hours prior to occupancy and continue during occupancy. These conditions must be maintained until a total of 14,000 cubic feet per square foot (4,500 cubic meters per square meter) of outside air has been delivered to the space.
OR
Option 2. Air testing
Conduct baseline IAQ testing, after construction ends and prior to occupancy, using testing protocols consistent with the EPA Compendium of Methods for the Determination of Air Pollutants in Indoor Air or as the ISO method listed in the table below. Testing must be done in accordance with one standard; project teams may not mix requirements from the EPA Compendium of Methods with ISO.
Demonstrate that the contaminant maximum concentrations listed below are not exceeded:
Contaminant Maximum Concentration EPA Compendium method ISO method Formaldehyde1. Formaldehyde is a naturally occurring VOC found in small amounts in animals and plants but is carcinogenic and an irritant to most people when present in high concentrations, causing headaches, dizziness, mental impairment, and other symptoms. When present in the air at levels above 0.1 ppm, it can cause watery eyes; burning sensations in the eyes, nose, and throat; nausea; coughing; chest tightness; wheezing; skin rashes; and asthmatic and allergic reactions. 2. A known carcinogen with no known safe exposure level. Formaldehyde occurs naturally, but appears in unnaturally high concentrations in many buildings because it is an ingredient in binders used in many building materials and furnishings. 27 parts per billion IP-6 ISO 16000-3 Particulates (PM10) 50 micrograms per cubic meter IP-10 ISO 7708 Total volatile organic compounds (TVOCs) 500 micrograms per cubic meter IP-1 ISO 16000-6 4-Phenylcyclohexene (4-PCH) * 6.5 micrograms per cubic meter IP-1 ISO 16000-6 Carbon monoxide (CO) 9 parts per million and no greater than 2 parts per million above outdoor levels IP-3 ISO 4224 *This test is required only if carpets and fabrics with styrene butadiene rubber (SBR) latex backing are installed as part of the base building systems.
For each sampling point where the maximum concentration limits are exceeded, conduct an additional flush-out with outside air and retest the noncompliant concentrations. Repeat until all requirements are met. When retesting noncompliant building areas, take samples from the same locations as in the first test, although it is not required.
Conduct the air sample testing as follows:
- All measurements must be conducted prior to occupancy, but during normal occupied hours with the building ventilation system started at the normal daily start time and operated at the minimum outside air flow rate for the occupied mode throughout the test.
- All interior finishes must be installed, including but not limited to millwork, doors, paint, carpet and acoustic tiles. Movable furnishings such as workstations and partitions should be in place for the testing, although it is not required.
- The number of sampling locations will depend on the size of the building and number of ventilation systems. For each portion of the building served by a separate ventilation system, the number of sampling points must not be less than 1 per 25,000 square feet or for each contiguous floor area, whichever is larger. Include areas with the least ventilation and greatest presumed source strength.
- Air samples must be collected between 3 and 6 feet from the floor to represent the breathing zoneThe breathing zone is the region within an occupied space between 3 and 6 feet above the floor and more than 2 feet from walls or fixed air-conditioning equipment. (AHSRAE 62.12007) of occupants, and over a minimum 4-hour period.
Potential Technologies & Strategies
Prior to occupancy, perform a building flush-out or test the air contaminant levels in the building. The flush-out is often used where occupancy is not required immediately upon substantial completion of construction. 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. testing can minimize schedule impacts but may be more costly. Coordinate with IEQ Credit 3.1: Construction IAQ Management PlanA construction IAQ management plan outlines measures to minimize contamination in a specific project building during construction and describes procedures to flush the building of contaminants prior to occupancy. — During Construction and IEQ Credit 5: Indoor Chemical & Pollutant Source Control to determine the appropriate specifications and schedules for filtration media.
The intent of this credit is to eliminate IAQ problems that occur as a result of construction. Architectural finishes used in tenant build-outs constitute a significant source of air pollutants and must be addressed to qualify for this credit.
Publications
SMACNA IAQ Guidelines for Occupied Buildings Under Construction
Project management guidance in maintaining satisfactory 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. of occupied buildings undergoing renovation or construction.
EPA Compendium of Methods for the Determination of Air Pollutants in Indoor Air
Provides step-by-step sampling and laboratory analysis procedures for the determination of selected pollutants in indoor air. The section of this document that is dedicated to testing methodology and procedures is most relevant for credit.
Indoor Air Pollution Report, July, 2005 California Air Resources Board
Outlines the health effects of indoor air pollution.
State of Washington Program and IAQ Standards
This standard was the first state-initiated program to ensure the design of buildings with acceptable 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..
Indoor Air Quality: A Facility Manager’s Guide, Construction Technology Centre Atlantic,
This publication is written as a comprehensive review of 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. issues and solutions.
Compendium of Methods for the Determination of Inorganic Compounds in Ambient Air, U.S. EPA
These methods have been prepared to provide regional, state and local environmental regulatory agencies and other users with step-by-step sampling and analysis procedures for the determination of selected inorganic pollutants in ambient air.
Web Tools
Healthy Building Network
Articles and resources on healthier building materials and issues of toxicity in the building industry.
EPA IAQ Design Tools for Schools Controlling Pollutants and Sources
Reference for best practices and strategies to implement 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 in Schools.
Controlling Pollutants and Sources, IAQ Design for Schools U.S. EPA
This EPA website offers detailed information on exhaust or spot ventilation practices during construction activity.
Organizations
Sheet Metal and Air Conditioning Contractors’ National Association, Inc. (SMACNA)
SMACNA is an international organization that developed guidelines for maintaining healthful indoor air quality during demolitions, renovations, and construction. The professional trade association publishes the referenced standard as well as Indoor Air Quality: A Systems Approach, a comprehensive document that covers air pollutant sources, control measures, 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. process management, quality control and documentation, interpersonal communication , sample projects, tables, references, resources, and checklists.
Technical Guides
IEQ Space Matrix
This spreadsheet categories dozens of specific space types according to how they should be applied under various IEQ credits. This document is essential if you have questions about how various unique space types should be treated.
Construction IAQ Management Plan
All Options
A construction IAQ management planA construction IAQ management plan outlines measures to minimize contamination in a specific project building during construction and describes procedures to flush the building of contaminants prior to occupancy. like this sample is required for both options of this credit, along with IEQc3.1. This example details a plan meeting both flush-out and testing requirements, leaving it open which one will be used.
Flush-Out Volume
Option 1 - Flush Out
This sample calculation demonstrates how one project figured out how long its flush-out needed to be, and how rental equipment was added to make it possible.
IAQ Testing
Option 2 - Testing
These test results and testing report from a LEED-CI project demonstrate the kind of information that needs to be gathered to document IEQc3.2, Option 2.
Construction Submittal
Documentation for this credit is part of the Construction Phase submittal.
LEED Online Forms: NC-2009 IEQ
The following links take you to the public, informational versions of the dynamic LEED Online forms for each NC-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):
- IEQp1: Minimum IAQ Performance
- IEQp2: ETS Control
- IEQc1: Outdoor Air Delivery Monitoring
- IEQc2: Increased Ventilation
- IEQc5: Indoor Chem. & Pollutant Source Control
- IEQc6.1: Control. of Systems—Lighting
- IEQc6.2: Control. of Systems—Thermal Comfort
- IEQc7.1: Thermal Comfort—Design
- IEQc8.1: Daylight & Views—Daylight
- IEQc8.2: Daylight & Views—Views
Version 3 forms:
- IEQp1: Minimum IAQ Performance
- IEQp2: ETS Control
- IEQc1: Outdoor Air Delivery Monitoring
- IEQc2: Increased Ventilation
- IEQc3.1: Const. IAQ Mngt.—During Const.
- IEQc3.2: Const. IAQ Mngt.—Before Occupancy
- IEQc4.1: Low-Emitting Mats.—Paints & Coatings
- IEQc4.2: Low-Emitting Mats.—Adhesives & Sealants
- IEQc4.3: Low-Emitting Mats.—Flooring
- IEQc4.4: Low-Emitting Mats.—Composite Wood
- IEQc5: Indoor Chem.l & Pollutant Source Control
- IEQc6.1: Control. of Systems—Lighting
- IEQc6.2: Control. of Systems—Thermal Comfort
- IEQc7.1: Thermal Comfort—Design
- IEQc7.2: Thermal Comfort—Verification
- IEQc8.1: Daylight & Views—Daylight
- IEQc8.2: Daylight & Views—Views
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."
LEEDuser is produced by BuildingGreen, Inc., with YR&G authoring most of the original content. LEEDuser enjoys ongoing collaboration with USGBC.
105 Comments
Do non-regularly occupied spaces have to be air tested?
Hello,
if you go for option 2, and conduct an air testing in a lab building, do you also need to do the testing in Non- Regularly occupied spacesRegularly occupied spaces are areas where one or more individuals normally spend time (more than one hour per person per day on average) seated or standing as they work, study, or perform other focused activities inside a building., such as carpark, toilets, mechanical rooms, etc?
Thanks, regards,
david
LEED 2009 EQ 3.2 Option 2 does not identify the kinds of spaces to be tested only that one test series be done for each separately ventilated space. This can be very confusing depending on the configuration of your HVAC system. If you have many fan-coil (VAVVariable Air Volume (VAV) is an HVAC conservation feature that supplies varying quantities of conditioned (heated or cooled) air to different parts of a building according to the heating and cooling needs of those specific areas.) units with separate thermostats then you might assume each area served by these must be sampled. I disagree and have not followed that line of thinking because it would result in far too many samples and be cost prohibitive. I try to identify the areas served by individual outdoor air intakes. LEED says each area sampled cannot exceed 25,000 square feet. If an area served by a single HVAC system (outdoor air intake) is more than 25,000 sf then two samples would be collected in that area. The other things that LEED states are that the outdoor air must be set at minimum and the sampling should be done in the least ventilated areas of the area being sampled. Regarding your question, I would not sample the areas you identified simply because they are not representative of what occupants will typically experience. If the building is too complicated regarding its HVAC system to figure out what separately ventilated areas means, then I would just use the one sample set per 25,000 sf rule-of-thumb.
As someone whose Masters Thesis was on 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 has been doing IAQ consulting for more than 25 years I find the LEED air testing requirements inappropriate for their stated goal. Unfortunately LEED V4 is going to make them near impossible to accomplish as written with them remaining of little value.
Multi Unit Residential Building - Phased Occupancy
I understand that in order to obtain this credit, 10% of the first 100 dwelling units and 5% of any additional units of the multi-unit residential building must be tested for the specified LEED parameters.
For our project this equates to 11 rooms. Our client intends to allow tenants to move into pre-rented units that have been completed (approximately 15 units) prior to construction being complete for the entire building.
My question is this: In order to meet the requirements of this credit, must all the 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. testing be completed prior to any residents moving in? Or can we take samples for a portion of the pre-rented rooms (i.e., just 3 units at first), and when construction is complete for the remaining units, then complete the IAQ testing to fulfill the requirements (the additional 8 units)?
This will mean some residents have moved into the building before all testing is complete.
I'm unsure of the implications as I suspect phased occupancy in a multi-unit residential building is fairly common? Any advice that can be shared would be much appreciated.
Erin, the credit language is clear that testing should take place before occupancy. Given that clear statement, I think you would need a ruling from GBCI to comply in the situation. While your situation appears common, I can't recall a LEED InterpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. that applies here. I would contact GBCI to see if you can proceed with a phased plan.
I've got this same issue. A client has decided they want to 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. Test a multi-family residential project in phases so that the lower floors can be occupied before the upper floors are completed. All major construction is completed, ventilation is running, upper floors will be separated.
any news on 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 ruling or other feedback on this situation?
Flush Out using exhaust fans / natural ventilation
Dear All,
Our project is aiming for the Flush-out option of this credit.
1) For the car parking (on the Ground Level), the air is exhausted by dedicated exhaust fans as per ASHRAE 62.1. For the flush-out, can we consider that exhausting a certain CFM of air will introduce the same CFM of fresh air (given that the parking is partly open to the external environment)?
2) What is the best way to achieve this credit for naturally ventilated areas under the flush out option? Since these areas aren’t served by HVAC systems providing fresh air, do we have another option to comply with the “Flush-out” option?
Thanks,
Omar,
1) Parking garages usually aren't considered in the flush out in my experience. However, your logic is correct regarding the exhaust = fresh air in.
2) This is covered in the information above: "In naturally ventilated buildings or other situations where using the HVAC is not possible or desired, alternatives such as temporary supply and exhaust fans placed in the windows are also possible. (Simply opening the windows is not enough, however.)"
IAQ Testing - no lab
I have a project that will be conducting the Air Quality Testing. I own the equipment that uses the EPA method for all the contaminants LEED lists, but I will not be conducting the testing thru a laboratory. Since the LEED Reference Guide clearly states: "This credit does not establish qualifications for the laboratory or those conducting the sampling", do you reckon the reports that I present will be valid, or must they be extended by a certified lab?
Yes, seems like this should work, Mario.
How are you going to measure the total volatile organic compounds (TVOCs) and formaldehyde1. Formaldehyde is a naturally occurring VOC found in small amounts in animals and plants but is carcinogenic and an irritant to most people when present in high concentrations, causing headaches, dizziness, mental impairment, and other symptoms. When present in the air at levels above 0.1 ppm, it can cause watery eyes; burning sensations in the eyes, nose, and throat; nausea; coughing; chest tightness; wheezing; skin rashes; and asthmatic and allergic reactions. 2. A known carcinogen with no known safe exposure level. Formaldehyde occurs naturally, but appears in unnaturally high concentrations in many buildings because it is an ingredient in binders used in many building materials and furnishings. without a lab? The EPA IP methods do not provide for a direct reading TVOC analyzer and the methods commonly available for direct reading formaldehyde are not sensitive enough. As someone whose Master Thesis was on 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 has been doing IAQ consulting for more than 25 years I know the LEED air testing methods and requirements are silly. My colleagues agree (Certified Industrial Hygienists and lab experts). No one consulted the experts when coming up with the parameters. For example, there is no EPA IP method for PM10 and the IP methods were created in 1990, have not been updated since, and are not commonly used by IAQ experts. I have done ten LEED air testing projects and the more I do them the more I realize what a waste they are. They don't achieve the goal of assuring good IAQ for the occupants.
Testing Approach
I have a middle school slated to be completed this coming summer.
It will be in late July.
Each classroom has a dedicated ground source heat pumpA type of heat pump that uses the natural heat storage ability of the earth and/or the groundwater to heat and/or cool a building. The earth has the ability to absorb and store heat energy from the sun. To use that stored energy, heat is extracted from the earth through a liquid medium (groundwater or an anti-freeze solution) and is pumped to the heat pump or heat exchanger. There, the heat is used to heat the building. In the summer, the process is reversed and indoor heat is extracted from the building and transferred to the earth through the liquid. The geothermal heat pump is more efficient than an air-source heat pump. Also referred to as a "closed-loop" system. air handling unit. Also, there are 5-6 roof mounted DOAS units.
The gym and cafeteria has H&V units.
Since the DOAS will most likely be supplying the outside air to all of the various heat pumps could the approach be to do sufficient tests in relation to the area being served by each DOAS and ignore the Heat Pumps for each classroom? The formula would then look like one test per 25,000 sq feet of each DOAS unit and one outside test to satisfy all indoor tests?
J.R., seems reasonable to me. However, LEED has loosened its specific requirements in this area so it's a bit of a judgement call. I'd recommend reviewing our advice above, if you haven't already.
Flushout of Nonoccupied Spaces
The 26,000 square foot building that I am working on has several spaces that are not served with supply air by the building's ventilation system, including toilet rooms and mechanical and electrical spaces. In order to meet the requirements of the Option 1 Flushout, does a supplemental fan system need to be provided to provide outside air to these spaces? If so, is this true of both occupied (toilet room) and nonoccupied (mechanical and electrical room) spaces?
In my experience, those spaces do not need to be flushed out directly. It is a gray area with LEED, one that I have not been called out on so I have ignored in some regards.
Typically, for our flush out calculation we use the "official" LEED project/building sq.ft. even though the unoccupied spaces aren't necessarily directly receiving ventilation.
Outdoor Air Contamination
We have a project that has failed 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. test by exceeding TVOCThe sum or total of all volatile organic compounds (VOCs) released from a product or measured in a space under certain defined conditions. levels. The team would like to flush the space with outside air prior to retesting to improve the result, however outdoor air quality is poor and we're afraid it could contribute to another failed test. Is there a protocol to take outdoor air contamination into account when performing indoor IAQ testing?
Norma, that seems like it would be extremely complex from a scientific and methodological perspective. I'm wondering what the intent of such a protocol would be. To ascribe certain contaminant levels to outdoor air, and thus hold the LEED project harmless for them? Hard to see how that would work. Could you filter the air effectively?
I suppose you would do this if it were an option, but simply following the flush-out procedure would be the easiest path to earning the credit at this point.
Thanks for the response, Tristan. The project is using a variable refrigerant flow system for HVAC. Our MEP estimated the flush to take about 9 months since it's a low volume system. We thought perhaps we could subtract the outside TVOCThe sum or total of all volatile organic compounds (VOCs) released from a product or measured in a space under certain defined conditions. levels or take a percentage from our interior levels.
Since you are still using the testing methodology, the flush out parameters are less restrictive as far as air temperature and humidity control than if you were using the flush out method. Would it be an option to bring in some temporary fans to expedite the flush out?
Norma,
I'm confused about how your ME arrived at 9 months for the flush out.
VRF systems still need to provide a minimum outside air to the space, usually this is achieved through the use of a dedicated outside air system (DOAS).
Let's say you were providing 0.15 CFM of OA/SF (California T24 Ventilation Minimum for an office space), the calculation would go like this:
0.15 CF/min per SF * 60min/hr * 24hr/day = 216 CF/day per SF
You can go Path 2 (phased flush out), which requires 3,500 CF/SF. At 216 CF/day it would take 16.2 days to complete. 16 days can definitely be impossible to fit in a tight schedule, but the 9 month calculation is unheard of for this credit. Even if you were providing half the CFM of OA/SF that is required in California (closer to the ASHRAE calc), you'd be at 1 month for Part 1 of Path 2.
During the occupied period, I could see there being an issue with supplying the 0.30 CFM/sf of ventilation required for Path 2 with your DOAS, but that's another story.
Excellent point, Dylan. I've been brought on to the project at the end to seal up the LEED construction documentation and am not sure how the MEP came to the flush rates. I'll check with the rest of the project team. Unfortunately, we're now too late for the flush process because of phased occupancy. We'll try Allison's approach and hope for the best!
To follow up on my last comment, I asked the team and it seems the 9 month flush process incorporated the occupancy phasing which began in 2/2012.
Renovation (occupancy never stopped) / 24-hour operation
Hello,
I am working on a project in Brazil with specific conditions that have brought up 2 questions concerning this credit. I'd really appreciate any opinions!
1) It's a major renovation + addition, but some portions of the existing area had almost no interventions. The bottom line is that occupation was never 100% interrupted, with the occupied areas always being isolated from the construction fronts. To complicate a little bit more, we're talking about a factory, so occupancy can't be interrupted completely because production can't stop.
For both Options 1 (Flush-Out) and 2 (Testing), the respective action (flush-out or testing) must at least partially occur prior to occupancy for credit compliance. For the new areas, that's fine. But for the existing production + administrative area, "prior to occupancy" doesn't actually exist for part of this project. The main production area didn't undergo any major construction works. How can we still pursue the credit?
Would it be acceptable to perform 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. tests as soon as construction is finished but while the existing portion of the building is occupied? Or, if not, to halt operation for a few days as soon as construction ends to begin the flush-out or perform the testing (if the Client is OK with that)? Or can the production and administrative areas where almost no interventions were made be excluded from flush-out / testing requirements, with an explanation to the USGBC showing which areas had almost no construction interventions?
2) Option 1, Path 2: For Phase II, "during each day of the flush-out period, ventilation must begin a minimum of 3 hours prior to occupancy and continue during occupancy" (Reference Guide, p.461). However, the factory runs 24 hours/day, so would the correct approach be to maintain the flush-out during 24 h/d every day until the 14000 cf/sf are reached?
Sorry the question got so long... Thanks for any input!
Alex
Alexandre
1) Perhaps you could exclude the existing occupied area from your LEED project scope. Otherwise I'd recommend getting a ruling.
2) Yes, 24h/d would be required. Obviously this wouldn't be required if you did the testing method as you eluded to in question #1.
Continuous flush out?
For Option 1 Path 2, can there be a time gap between when the pre occupancy ends and post-occupancy flush out begins? Or does one have to immediately follow the other?
Under Option 1 Path 2 the credit states:
"Once the space is occupied, it must be ventilated at a minimum rate of 0.30 cubic feet per minute (cfm) per square foot..."
I read this to mean that once the space is occupied it must continue to be flushed at an elevated level until the flush out is complete. Otherwise, you are exposing the occupants to contaminates until you get around to finishing the flush out.
above 60% relative humidity during flush out
Will a a flush out with above 60% relative humidity be acceptable provided there is a valid reason? The main reason is that further attempt to obtain 60% humidity may affect the complex DDC program set up of HVAC Equipment.Is this a valid reason? What are documentations needed to approve this case ?
Benj, in my opinion the 60% RH requirements is abitrary and overly restrictive, but it is also fairly clear and rigid. If it's not possible for you to achieve I would recommend using the testing option.
IAQ Testing method
It's clear that for this credit, LEED only accepted 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. testing using EPA or ISO method. But we find it difficult to get certified lab that uses those method as our project is located outside of US. There are some lab offered us to use NIOSH method instead. Is it possible that LEED would acknowledge or give us leniency to use this method?
Yasir, I think it might be possible. This is not one of the credits for which USGBC has offered a non-U.S. Alternative Complaince Path, but they have signaled openness to offering such paths for other credits. I would contact GBCI with your request and see what they say. And please post back here what happens.
Dear Tristan,
Luckily you wont have to contact GBCI. Because, It turned out that our building ventilation design have already doing the "flush out" plan. So we have done the calculation needed and submitted it to our project administration. Right now, I still wait for GBCI respond. Thank you for your concern.
Occupancy Date Comments
I have received 2 review comments in the past few weeks that take issue with the fact that the "Substantial Completion" or "Estimated date that project will be ready for occupancy" date on the Pform is not exactly the same as the "Occupancy" date on the EQ3.2 form.
I don't interpret these two dates as the same anyway. An estimated or substantial completion date that the design team puts down on a Pform that is likely submitted long before the project is complete is basically never going to be the same as an actual Owner driven occupancy date. Not unless you are doing a combined submittal and make them the same, despite the fact that what is being asked is different.
So now I'm in the position of explaining that the dates aren't the same because they aren't asking for the same thing in both places.
Is anyone else seeing these comments? Does it make sense to have to make a pre-emptive narrative statement that these dates actually aren't the same to forestall the comment? Or are they actually indicating that we should be making those dates the same whether they are or not?
I think you have to explain how this could be different. Thanks for the heads up. I've got two projects going in for construction review soon and both have a significant separtion between Substantial Completion and Occupancy. I will be sure to explain the difference in the write up.
Please note the following instructions on the PI4 form:
"Enter actual or estimated start dates for each of the following design and construction stages. If date is prior to the date of initial application, it is assumed to be actual."
This could be why there was an issue. I'd suggest updating your PI4 form with the update information when you resubmit.
Can credit 3.2 be earned from a re-test post occupancy?
I just completed 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. assessment for credit 3.2. Unfortunately, the building failed with excessive levels of particles and VOCsA volatile organic compounds (VOCs) is a carbon compound that vaporizes (becomes a gas) at normal room temperatures. VOCs contribute to air pollution directly and through atmospheric photochemical reactions (excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides and carbonates, and ammonium carbonate) to produce secondary air pollutants, principally ozone and peroxyacetyl nitrate.. The owner accepted occupancy two days after the site visit and 5 days before I even got the results back from the lab. I basically came in on the 2nd to last day of the project – I know bad idea, not my call.
Is it now too late to pursue this credit or can we still conduct a building flush-out and test post occupancy and apply for the credit assuming that the building passes the second time around?
Thanks,
- Bob
Bob, curious if anyone else has experience here, but I would assume you can't earn the credit, based on the clear requirement that the flush-out be conducted pre-occupancy (in order to protect occupants from contaminants).
Although it may not qualify you for the credit, it sounds like a flush-out may be a good idea, though.
Tristan, thanks for the quick reply. I agree that the verbiage is very clear about “pre-occupancy”, but re-testing is not realistic if we have to postpone occupancy. CM’s and building owners are not going to wait for initial lab results, report, re-test, and report once again when they are staring at a brand new building that otherwise appears to be move-in ready.
What if the flush-out takes place during off hours and re-test occurs during normal occupied hours?
I may have commented on this before. Tristan is correct. Testing and retesting must occur before occupancy. If you are pursuing the testing method you are risking the credit if you don't budget time for retesting.
In the LEED reference guide it says: "If a test sample exceeds the maximum concentration level, flush out the space by increasing the rate of outside air. While the credit requirements do not prescribe the duration of the flush-out, those responsible for testing should make an evaluation based on the contaminate, its concentration, and the potential source... Resample and confirm compliance BEFORE allowing occupancy."
Yea, I'm on the same page as you guys. I'm just getting ready for the GC and owner to freak out. Don't shoot the messenger, right?
Robert, good luck! I think the main point is that occupants are currently or will be exposed to contaminants, and nothing you can do now can prevent that. There is a alternative for an accelerated flush-out during occupancy, but it seems even too late for that.
Just to confirm, we had a re-test six days after occupancy and the credit was rejected upon preliminary review. Technical advice reads "this credit requires that the testing is COMPLETE AND COMPLIANT [my caps] prior to occupancy. Please confirm the date of occupancy and the dates of the testing process." I don't see any way out of this one.
Flushout calcs for Option 1 Path 1
To achieve the required time needed for flush out, do we only take into consideration the OA louver volume (CFM)? So if we have a total flush volume of 15,000,000 and the OA louver has a CFM volume of 250 then our flush out time would be 41.7 days. Is this correct? I would think we would have missed some variables by doing that.
Mark
Are you sure there is only 250 cfm of outside air coming into the HVAC? The flow seems to be too small unless the building is also very small. What are the dimensions of the areas to be flushed out?
15,000,000 CF of Air / 14,000 CFM/SF = 1071 SF.
Hopefully your HVAC unit is capable of EconomizerAn economizer is a device used to make building systems more energy efficient. Examples include HVAC enthalpy controls, which are based on humidity and temperature.. In which case, the unit may have a minimum OA of 250 CFM but a maximum OA of 100% of the total SA.
If the unit doesn't have economizer capabilities. Consider bringing in a temporary fan/conditioning unit that can bring in OA (make sure you stay within the temperature and humidity requirements) to reduce the flush out time. Or if you have operable windows open the windows while flushing and go with the testing method.
Timing of IAQ testing compliance
I am part of a LEED NC 2009 for Retail project that intends to pursue Option 2 -- Air Quality Testing -- for this credit. The retail requirements differ from the NC requirements in that projects are allowed to perform air quality testing up to 14 days into the occupancy period, because "retail project turnover typically happens fast."
I understand that if one or more air quality samples exceeds maximum concentrations, projects may flush out and then repeat until all samples are in compliance. I am unclear about the allowed timing for repeat tests. Must a project 'pass' air quality tests by 14 days into occupancy (or, by time of occupancy for normal NC projects) in order to earn the credit, or is it permitted to perform repeat tests as necessary after this 'deadline' as long as the initial test occurred beforehand?
Something to consider is that air quality testing results can take a week or longer to get back.
Anders,
I had some more time to look into the NC requirements.
In the credit language it says "All measurements must be conducted prior to occupancy." Later in the manual it specifically says "The project team should resample and confirm compliance before allowing occupancy".
If the Retail requirements allow you to shift the occupancy period out 14 days for the flush out method, IMO you could make that your deadline for passing the testing requirements.
Like I said above you will need to factor in the fact that it could take 1-2 weeks to get test results back to even know if you have passed.
Anders & Dylan,
I work with the LEED Canada program and for our projects we have the option of using portable equipment as per 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 #505. I imagine that the USGBC may allow something similar. With portable equipment you can receive instantaneous results and therefore you will know if you pass or fail the same day. This will method would save you lots of time if you are able to utilize this option with the USGBC's LEED program.
The following equipment was allowed by the CaGBC through CIR #505;
- Portable Photo Ionization Detector (PID), calibrated with the help of gas cylinders at 0 and 7.5 ppmParts per million. of isobutylene for detection of VOC’s.
- Portable electrochemical oxidation detector for carbon monoxide, calibrated with the help of gas cylinders at 0.5 and 105 ppm.
- Continuous photometric particulates detector, with a built-in separation head for particulates of 10 microns (PM10).
- Portable formaldehyde1. Formaldehyde is a naturally occurring VOC found in small amounts in animals and plants but is carcinogenic and an irritant to most people when present in high concentrations, causing headaches, dizziness, mental impairment, and other symptoms. When present in the air at levels above 0.1 ppm, it can cause watery eyes; burning sensations in the eyes, nose, and throat; nausea; coughing; chest tightness; wheezing; skin rashes; and asthmatic and allergic reactions. 2. A known carcinogen with no known safe exposure level. Formaldehyde occurs naturally, but appears in unnaturally high concentrations in many buildings because it is an ingredient in binders used in many building materials and furnishings. detector that measures the coloration of a chemically treated paper patch after 30 minutes of exposition.
I hope this helps.
Adrienne
Adrienne
In the US, the testing protocols do not allow direct reading instrumentation for compliance for some of the 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. parameters. For example, for VOC, which photoionization would be a great tool for TVOCThe sum or total of all volatile organic compounds (VOCs) released from a product or measured in a space under certain defined conditions. must be analyzed individually using GCMS laboratory procedures. Direct reading can be used in some cases as a screening tool prior to collecting the final air samples. Same scenario is for formaldehyde1. Formaldehyde is a naturally occurring VOC found in small amounts in animals and plants but is carcinogenic and an irritant to most people when present in high concentrations, causing headaches, dizziness, mental impairment, and other symptoms. When present in the air at levels above 0.1 ppm, it can cause watery eyes; burning sensations in the eyes, nose, and throat; nausea; coughing; chest tightness; wheezing; skin rashes; and asthmatic and allergic reactions. 2. A known carcinogen with no known safe exposure level. Formaldehyde occurs naturally, but appears in unnaturally high concentrations in many buildings because it is an ingredient in binders used in many building materials and furnishings.. In the other hand CO can indeed be measured used the direct reading instrumentation.
Defined Flush out Area
Hello everyone - Our project's registration details reference building square footage as 51,441. However, we've only finished 40,100 sqft. Given that our registration makes reference to the 51,441 value, will our flush calculations be driven by actual finished area or total building area? I ask the question because our mechanical sub submitted his calcs based on finished space?
thanks-
tom
Thomas,
We've come across the same question on our projects as well. The LEED manual did not seem to provide a definitive answer so we have gone with the project registration square footage to be on the safe side.
In your case, there is a significant difference in sqft and it would probably be worth it to flush out less sqft while providing the LEED reviewer with an explanation/justification.
Consider reviewing what sqft is being ventilated by your HVAC systems. If the unfinished area is not ventilated than you don't have an opportunity to flush it out anyway.
Option 1 Path 2
Hello. We have a building looking to meet the requirements for Option 1 Path 2. In the credit language it states that the flush is to stop at the end of occupancy for that day. The operating hours are from 9am-6pm. Seeing there's a 3 hour minimum in which we start the ventilating, are we allowed to just ventilate 24 hours a day until we reach 14,000?
Yes. You can run the ventilation 24 hours a day during the post occupancy part of "Option 1 Path 2."
However, you will need to supply 0.3 CFM/SF of OSA during that time if that is more than your IEQp1 OSA minimum (it usually is). Some systems can't handle the load of that much OSA during certain times of the year. Your sequence of operations may need to be altered to ensure comfort during the occupied periods.
Another thing to consider is that if you have a 100% OSA system and it is only sized for the minimum OSA requirements then you may not be able to meet the 0.3 CFM/SF OSA requirements.
Thank you for your quick response. You're correct. The .3 is more than our design value. We have one RTU that is OSA only and it doesn't supply enough to ventilate at that rate. However, we plan to have the TAB consultant provide documentation that opening the dampers x% on the other 3 units will contribute an assumed value to the ventilation. We are hoping this will satisfy any questions GBCI may have. Would you say that is a reasonable approach? Thank you for the additional information on the sequence of operations, that is one thing we had left out.
That sounds good.
I would also recommend having your CxAThe commissioning authority (CxA) is the individual designated to organize, lead, and review the completion of commissioning process activities. The CxA facilitates communication among the owner, designer, and contractor to ensure that complex systems are installed and function in accordance with the owner's project requirements. or GC install temporary temperature and humidity sensors in the space. These sensors can trend data during the flushout to ensure/prove you are meeting the temperature and humidity requirements of the credit.
Ok Great. The one unit that is OSA only, has sensors and has been programmed to trend the date at given intervals. This is the only system that will operate for the initial 3500 flushout to ensure the 60/60 requirements. Will we need to provide trending data for the assumed value units? Or can we just supply the trending date for the OSA unit? Again, thanks for taking the time to address my questions.
The temporary sensors would be in the space to ensure that the space is maintaining the 60/60 requirement, not just that the unit is supplying 60/60.
Currently the LEED form does not require that you upload any data for "proof" that your ran the units for the required amount of time and that you maintained the 60/60 requirement. However, the reviewer may question how you "could" prove it if you didn't install temporary temperature and humidity sensors if you don't already have permanent sensors.
I recommend you describe your method to measure the OSA quantities and maintain 60/60 in the narrative to avoid questioning.
What sort of methods have people used to measure the OSA quantities? Would it have to be readings from an OA CFM meter? Or would it be acceptable if you calculated it from fan speeds, damper positions, etc?
Daniel,
There is a NC2.2 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 (ID#2099) that clarifies that you can use a current transducer (CT) to check fan status on an 100% OSA system. However, it states you cannot use a CT if the system is not 100% outside air or constant volume.
So damper position and fan speed will not work. The basic reason is that air flow quantities may still vary based on different pressure situation.
Where can you look up these CIRs? usgbc.org? My question really is will they accept methods for measuring the OA flow for flush out other than using a flow meter?
https://www.usgbc.org/leedinterpretations/lilanding.aspx
They would likely accept using a CT for flush out if you are running the system 100% OA or at a constant volume.
IAQ Flush Out
I would like to know what documentation is acceptable to USGS on the flush out process? Is there documentation from the BAS system required? Just wanting to make sure that I have all the required documentation to insure that I achieve the requirement before I being the building flush out
The latest form actually only requires you to: "Describe the flush-out procedure. Include flush-out date(s), outdoor air delivery rates, internal temperature, and relative humidity."
It does not specifically ask that you upload proof. However, I would recommend trending on the BAS if you have one.
On our projects we require that the BAS trend OA and SA quantities, space temperature and then have the contractor install Humidity sensors to trend during the flush out period. This gives us proof that the system perform per the LEED guidelines in case the form changes at some point or if the LEED reviewer has comments/questions.
IAQ Management Plan
We used an EQc3.1 plan and used the testing method to meet EQc3.2 requirements. I'm looking at the online form now and wonder what's meant by this: "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 was developed and implemented at the project building. The plan includes post-construction IAQ management measures. An Indoor Air Quality (IAQ) Management Plan highlighting IAQ management practices is required for credit compliance." Is that equivalent to the plan used for EQc3.1 or is another plan for post-construction IAQ management required?
Maura- we've always used the plan for IEQ 3.1 with no problems.
# test sites for condo project?
Your comment in "Bird's Eye View" above states:
"Buildings with large numbers of identical rooms with separate ventilation zones—such as hotel rooms or apartment units—have been allowed to perform random sampling as an alternative approach in situations when the delivery of outside air—on an air-change-per-hour basis—and the materials in a ventilation zone are identical. Project teams should confirm with GBCI that this is still applicable in LEED 2009."
If our condo has 5 different unit "types", is it feasable to only sample 1 of each unit type? not exactly sure what "random" means.
They definitely handle this type of thing on sort of a case by case basis. Proposing sampling one of each unit type may be very well received, but it will likely depend on the number of units you have. I have never seen them accept sampling that accounts for less than 10-15% of the total number of units or square footage, so if one of each unit type is less than this percentage, you will likely need to do more. As far as random goes, if you let the testing agent pick which of each type of unit to sample instead of you directing him to a certain unit in particular you should be in pretty good shape.
# Of Testing Locations
Our project single floor mixed use space, with a large single heat recovery unit providing outside air to all of the spaces. Additionally there are 17 plenum return heat pumps located throughout the spaces used to condition the air in the spaces. Since all of the spaces are normally occupied, would we be required to take a (1) 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. sample or (18) samples (17 heat pumps & 1 HRU). Sampling method wont work for our type of building, but I'm curious if the OA serving the space is considered the ventilation system or if the heat recovery unit and heat pumps are all considered seperate ventilation systems.
Daniel,
Did you receive any comments in regards to this? This would answeer my question also. Thanks!
April,
The general consensus I recieved was that this would require (2) seperate tests (one for the HRU OA zone and one for the Docking BayA bay is a component of a standard, rectilinear building design. It is the open area defined by a building element such as columns or a window. Typically, there are multiple identical bays in succession. served by Natural Ventilation), since the Heat Pumps are not Ventilation units based on ASHRAE mechanical design practices. Hope this helps.
IAQ Testing using screening tool.
Has anyone had experience with meeting the 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. testing requirements using the Directsense IAQ Plus Screening tool from Graywolf Sensing Solutions. I am curious if testing via this method will satisfy LEED requirements. Here is a link to the product description and information about meeting LEED IEQ3.2:
http://www.wolfsense.com/app_notes/GrayWolf_AppNote_LEED32.pdf
Thanks.
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