This credit requires compliance with a varied group of items that cumulatively help keep pollutants out of the indoor air. These requirements include self-closing doors on janitors' closets, MERVMinimum efficiency reporting value. 13 filtration on mechanical equipment, and entryway trackoff systems.
Compliance will require the coordination of team members—including the mechanical engineer, architect, plumbing engineer, and contractor—and also impact project design and operations. The basic requirements are:
In addition to tobacco smoke, covered in IEQp2, one of the greatest sources of indoor pollutants is the dirt and other contaminants brought into buildings on people’s shoes. This material is tracked through the building interior, increasing the need and frequency for cleaning, and the wear on interior finishes. Dust can also be introduced into ventilation systems and distributed throughout a building, negatively effecting indoor air quality.
While it takes a lot of coordination to meet the many credit requirements, this is generally a low-cost credit. The most significant impact may come if MERVMinimum efficiency reporting value. 13-compatible air-handling equipment is not initially specified, as redesigning mechanical systems can be costly. In some situations, especially when using heat pumps, HVAC systems cannot accept MERV 13 filters because they are not able to draw air through such a thick filter.
MERV 13 filtration results in an energy-use trade-off. While MERV 13 filters offer a greater level of air filtration and, consequently, increased indoor air quality, they also increase resistance to airflow and fan energy loads. If you can separate space conditioning from ventilation and use radiant systems for all or most of the space conditioning, you can minimize this energy penalty.
Multifamily residential and hotel projects may have difficulty achieving this credit due to the MERVMinimum efficiency reporting value. 13 filtration requirement. These projects often do not have base-building HVAC systems; they use PTACs instead, which generally cannot be fitted with MERV 13 filters. If a project has forced air systems and MERV-13 filtration is not used, then you cannot pursue or achieve this credit. Naturally ventilated buildings do not have to meet the MERV 13 filtration requirement, as air filtration will not be part of system design.
When LEED 2009 was launched, this credit included language calling for containment drains in laboratory spaces where chemicals are mixed. However, the requirement was vague and it wasn't clear how to document it. Fortunately, in the July 2010 LEED addenda issued by USGBC, this requirement was removed.
There is no definitive information from USGBC on this one way or another. It is recommended that project teams do their best to find low-emitting options for IEQc5, and that IEQc4.3 compliance is recommended.
However, LEEDuser has heard that project teams have had success not including track-off mats, such as the type with grilles and small strips of carpeting. Also, mats that are removed for cleaning are not permanently installed and thus not subject to credit requirements. If used as track-off surfaces, carpet tiles should be certified, however, and are available with the requisite certifications.
There is not an official glossary definition that LEEDuser is aware of. However, various references indicate that LEED views "high volume" as one or more printers in an area totaling more than 40,000 copies (20,000 double sided) per month. The number is based on "expected" use, not capacity. This definition can be found in 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. #1938 issued 1/7/2008, for example, and although that Interpretation is not applicable to LEED 2009, the number 40,000 has appeared in enough places that we view it as a solid number.
If the copiers print less than 40,000 pages/month (20,000 pages double-sided) you do not need to install dedicated exhaust, self-closing doors and deck-to-deck partitions. Additionally, if you use printers that do not emit VOC’s or other harmful contaminants into the indoor environment, you can make a case for exemption.
LEED Interpretation #10098, dated 8/1/2011, states that "The intent for the entryway system (grilles, grates, walk-off mats) is to capture dirt and dust. An exception to the 10 foot length and/or indoor location is acceptable provided your alternative solution meets this intent and is thoroughly justified."
Project teams have been successful including exterior mats that are protected from the weather and regularly cleaned. LEEDuser has not heard of a project successfully gaining an exception to the 10-foot requirement, however. In situations where an irregular shaped mat makes sense, teams should consider whether people entering the building will travel at least 10 feet over a mat, and not be able to short-circuit it. A short narrative explaining the impediments and how your solution meets the standard established by the LEED Interpretation is recommended.
These entrances are those that are used by building occupants on a regular basis. If your project has unique circumstances where certain building entrances are not regularly used or do not serve building occupants, they may be excluded. For example, emergency exits that are not used as regular entrances can often be excluded.
LEED Interpretation #5266 made on 05/30/2007 states that the requirements are applicable only to entrances from the outdoors.
Yes, carpet tile applies per LEED Interpretation Ruling #10252. Some project teams have preferred to use carpet tile due to ease of maintenance and avoidance of trip hazards. The carpet tile must be specifically designed for entryway systems. Regular carpeting that is not designed for this purpose and does not have regular cleaning is not applicable.
LEEDuser has not seen an official ruling on this, but our expert consensus is no.
One, replacing a physical control with a policy control is a bit of a downgrade. Two, 100% avoidance of hazardous chemicals in cleaning is unlikely. The green cleaning purchasing credit in EBOM, for example, considers 30% good enough to earn the credit. Also, the thresholds, categories, and standards referenced in that credit will only go so far in preventing use of any cleaning supplies that might generate gases or chemicals that should be exhausted.
Identify programming requirements for special-use spaces such as high-volume copy rooms (40,000 pages or more per month), laboratories, art rooms, chemical storage, housekeeping areas, and other spaces that may expose occupants to hazardous materials.
Identify space requirements for entryway walk-off mats. Review the impact that the required ten-foot entryway systems will have on common areas, lobbies, and other interior spaces adjacent to building entries. Remember that the entryway systems have to be installed at all regularly used entrances from exterior spaces, including entrances from a covered parking garage into the building.
The LEED Reference Guide states that entryway systems need to be on the interior of the building or in an interior vestibule. It is recommended that projects pursuing this credit with the intent of using an exterior entryway system (either permanent or rollout) consult the GBCI or your certification board via email to verify credit compliance. It is usually accepted that exterior walk-off systems are allowed if they are properly sheltered from weather; that would typically mean some kind of roof, but additional shelter may be warranted depending on local conditions.
Review the potential for using MERV 13 filtration on ventilation systems. Systems with low fan power or filtration size limits may not be able to accommodate MERV 13 filters. Also, many residential and hotel projects use PTACs, or similar packaged systems, which cannot accommodate MERV 13 filters. Any mechanical ventilation must be designed with MERV 13 filters in mind.
If you can use radiant heating and cooling for space conditioning and separate that function from ventilation, you’ll be moving a lot less air and meeting the MERV 13 requirement won’t be nearly as big a deal, due to fewer and smaller ducts and filters.
Include mechanical engineers and design consultants for special-use spaces such as science labs early in the design process.
This is usually a low-cost credit. However, the MERV 13 filtration requirement can increase operational costs for added energy use and more frequent filter changes. If your ventilation system is not typically sized to accommodate a MERV 13 filter, you may have to choose a new system or have one custom-designed, which can add cost. Customization may include resizing ductwork, increasing fan capacity to maintain air delivery despite the added resistance of MERV 13 filtration, or other modifications to system design.
Design an adequate space for ten-foot entryway systems at all regularly accessed building entries. Evaluate all other building entrances—such as employee and service doors—for regular use, which may require entryway systems or roll-out mats.
Determine the type of entryway system that's best for your project. If you install permanent grates, grilles, or slotted entry systems, you will not be required to have a plan for cleaning, although those systems will still need periodic cleaning (less frequently than roll-off mats). However, if you decide to use rollout mats, you'll need to have a contract in place for weekly cleaning. The contract for weekly cleaning can be incorporated into any existing contract but must be clearly spelled out.
While roll-off mats are acceptable, additional documentation (service contracts and schedules) is required to confirm that the mats will be cleaned on a weekly basis. They cost more up-front, but permanent entryway systems provide better performance, require less maintenance, and are easier to document for LEED compliance.
Entryway systems should be climate-specific. For example, regions with high rainfall may choose high void-volume mats—for trapping dirt below the mat surface and fast drying. In regions where mud and snow are a greater source of contaminants, open-loop entry mats may be more appropriate.
Design in space for additional ductwork that might be needed to provide designated exhaust for all garages, high-volume copy rooms, janitors’ closets, science labs, workshops, art rooms, or any other spaces that may be used for mixing and storage of chemicals or hazardous materials. You need to design the exhaust system so that each space with hazardous material has negative pressure in respect to adjacent spaces. For each of these spaces, be sure to include self-closing doors, and deck-to-deck partitions or hard-lid ceilings.
Strategies for space planning may include:
When planning for space allocation to meet credit requirements, consider strategies like merging exhaust systems into a single, main, designated exhaust, or stacking chemical use areas over each other on different floors to minimize ductwork.
Provide adequate space for storage and containment of hazardous liquids.
Hazardous storage containers should be located in a secure area outdoors and away from air intakes.
Develop an outline of all the IEQc5 requirements that apply to your project, and confirm that the schematic design accommodates each one.
Adding ductwork to meet credit requirements can add costs; incorporate space-planning strategies to minimize this issue.
Once programming and space allocations have been determined, confirm that each of the relevant credit requirements is met, as detailed below.
Confirm that all mechanical ventilation systems can accommodate MERV 13 filtration on outdoor and make-up air supply.
If roll-out mats are used, make selections appropriate to the climate. The following specifics are also recommended in the LEED Reference Guide:
Confirm that chemical disposal areas meet local codes for separate drain lines or containment drains.
Confirm that all chemical storage areas, high-volume copy rooms, etc. have:
Locate hazardous waste storage containers away from outdoor air intakes.
Develop all required documentation for LEED submittal, including floor plans indicating locations and lengths of entryway systems, wall details (for deck-to-deck partitions), mechanical drawings showing locations of designated exhaust systems, and mechanical schedules specifying MERV 13 filtration.
For all spaces that may contain hazardous gas (such as garages, janitors' closets, and labs), calculate exhaust rates to confirm adequate negative pressurization. The pressurization requirements are:
Include credit requirements in all appropriate specification sections. Include the general requirements in Division 1 and others in specialties or furnishings (for the entryway systems) and HVAC (for filtration and other mechanical requirements).
Projects that use their own maintenance staff for regular cleaning of rollout entryway systems must provide a cleaning schedule and narrative along with their documentation.
Develop documentation customized for LEED submission—complete with LEED-related notes, callouts, and details—concurrently with the finalized construction documents.
The contractor is the signatory for IEQc5, even though it's a design credit. Have the contractor review 100% of the construction documents to confirm compliance before completing the design submittal. Otherwise, the credit may have to be deferred until the construction submittal.
Use temporary ventilation systems instead of the permanent HVAC units during construction. This prevents contamination of new ductwork during the construction process.
Use MERV 8 filtration on any permanent mechanical system equipment used during construction. This adds to construction management tasks and could easily be overlooked and lead to loss of the credit. (This requirement appears in the LEED Online credit form as of 10/09, even though it does not appear in the credit language or LEED Reference Guide.)
Make sure that compliance and coordination with this credit is called out in the IAQ management plan if your project is pursuing IEQc3.1: Construction Indoor Air Quality Management Plan—During Construction.
Ventilation and exhaust systems and proper filtration should be included in the commissioning scope for the commissioning credits EAp1 and EAc3.
Provide appropriate training for maintaining entryway systems. If roll-out mats are used, maintain a weekly schedule for cleaning.
Provide adequate training and education for all O&M and cleaning staff in appropriate handling, use, storage, and disposal of hazardous liquids.
Provide appropriate resources and training for O&M personnel to maintain mechanical equipment with MERV 13 filters.
Mechanical systems have to be commissioned to meet the commissioning prerequisite EAp1. The commissioning agent's scope should include confirming appropriate MERV ratings on filtration media and proper operation of designated exhaust systems.
Excerpted from LEED 2009 for New Construction and Major Renovations
To minimize building occupant exposure to potentially hazardous particulates and chemical pollutants.
Design to minimize and control the entry of pollutants into buildings and later cross-contamination of regularly occupied areas through the following strategies:
Projects in East Asia may use filtration media classified as high efficiency (高中效过滤器) or higher as defined by Chinese standard GB/T 14295-2008 (空气过滤器).
Design facility cleaning and maintenance areas with isolated exhaust systems for contaminants. Maintain physical isolation from the rest of the regularly occupied areas of the building. Install permanent architectural entryway systems such as grills or grates to prevent occupant-borne contaminants from entering the building. Install high-level filtration systems in air handling units processing both return air and outside supply air. Ensure that air handling units can accommodate required filter sizes and pressure drops.
This updated version of the 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. Up to date, 2nd Edition.
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. This is the 1st edition.
The Janitorial Products Pollution Prevention Project is a governmental and nonprofit project that provides fact sheets, tools, and links.
According to the website, 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. Design Tools for Schools “provides both detailed guidance as well as links to other information resources to help design new schools as well as repair, renovate, and maintain existing facilities. Though its primary focus is on indoor air quality, it is also intended to encourage school districts to embrace the concept of designing High Performance Schools, an integrated, whole building approach to addressing a myriad of important—and sometimes competing—priorities, such as energy efficiency, indoor air quality, daylighting, materials efficiency, and safety, and doing so in the context of tight budgets and limited staff."
Environmental Building News feature article describing the benefits and design choices for entryway walk-off systems.
Environmental Building News feature article explaining the various types of air filters, how their performance is measured, and ways to optimize their effectiveness.
Facilitiesnet article covering the basics of air filtration, drawbacks and benefits, standard practices and basic concepts.
Table of filtration efficiencies and their subsequent filtration properties and common applications. Good background on MERVMinimum efficiency reporting value. 13 filtration.
A floor plan like this project example is required to document the presence of entryway track-off systems, length and location. Note that this sample shows six-foot entryway systems because the project predated LEED 2009. For LEED 2009, the systems need to be ten feet in length.
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):
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.
How are people proving the differential pressure of applicable spaces in credit documentation? What tool is being used to determine the pressure differential, obviously not all projects will be doing blower door testing.
They don't actually require you show your work - you just check that you comply. There is an equation you can use to do the calculation for yourself. It is in the comments below.
We have a mixed use building major renovation on a Government site. There are shops and maintenance areas, some that have unique exhaust systems. Our designer has addressed these requirements. There are also a number of meeting rooms, office space of varying size from single senior staff as well as rooms with anywhere from 3 to 30 staff. No contract information was provided regarding walk-off mats or printers. During design, our client provided the following:
1. Our client determined that our recessed walk-off grills should not be longer than 6 ft. To meet the requirement for this credit, can we add 4 ft of roll-off mats?
2. Additionally, the documentation requirements are that we provide the maintenance requirements for the roll-off mats (i.e. a minimum of weekly cleaning). Do we also have to provide documentation from our client that they have a contract to clean the mats weekly?
1. Client indicates they will install low volume, convenience printers in areas designated for office workers supporting shops in our building and other shops in a industrial type area. These printers would be purchased under a separate contract. No further guidance was provided. Our designer has provided suggested locations in his design, providing one convenience printer per every 15-30 desks, but this is not part of his design requirements. The client has approved his design which shows the suggested convenience printer locations. Do we need to wait for the client to purchase printers or use the suggested locations provided in design?
Regarding low-volume printers - no you don't need to wait for them to be purchased. LEED is a design tool and you are indicating your design intentA written document that details the ideas, concepts, and criteria that are determined by the owner to be important to the success of the project. on most credits.
That answer sure does make my life easier, thanks!
I am working on a project in SE Asia. As with many resorts in SE Asia the lobby is sheltered but open to the exterior of the building. Does this count as the building interior or would entry way mats have to be placed at the interior of entrances to fully enclosed spaces?
The intent of the requirement is to remove contaminants from shoes before they are tracked into enclosed spaces and create indoor air quality issues. Typically these need to be inside the building, and precedent indicates that review teams take a quite strict view of the requirement for mats to be inside the building, although limited exceptions are made for renovated buildings.
That said, the regulations were not created with SE Asian architectural design in mind, and depending on the design, location and use of the property it may be possible to convince the review team that the credit intent is satisfied by placing mats at the entrance to the sheltered lobby. For example, It appears unlikely that this solution would be acceptable for an office building lobby in Bangkok where air pollution is high and dust will contaminate the lobby, while it may be acceptable at a remote island hotel where sand should be removed at the building entrance.
In any event, I would recommend submitting 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 to confirm the strategy if achieving the credit is important to your certification strategy.
LI#5219 addresses an issue similar to yours: http://www.usgbc.org/leed-interpretations?keys=5219. Just as your question suggests, this ruling exempts open-air spaces, but requires walk-off provisions at entries into enclosed spaces.
However, because IEQc5 criteria have changed slightly since LEEDv2.2, portions of this interpretation may not be applicable to LEED-2009. To be safe, you may choose to request an interpretation from the USGBC citing LI#5219 and inquiring how this ruling might apply to your project’s specific conditions.
Did you get any feedback from USGBC regarding this subject? In our project there is a dining room which is connected to an outside terrace. The terrace has a roof and a short surrounding wall and people can access it only from the inside. My case is in some way similar to yours and I would like to confirm if this kind of entrance between the terrace and the dining room need a 10feet long entryway mat?
Balconies accessed only from the interior don't need entryway mats. I would apply that to a terrace as well.
Agata - We had a similar design, a dining room which is connected to an outside terrace. The terrace has an open grid/ trellis roof and a short surrounding wall with trellis. Similar scenario, people can access it only from the inside. However, there are gates for emergency egress. We did not provide a 10feet long entryway mat in this area and were awarded the credit. The USGBC reviewer questioned it, but we indicated these doorways would be exempt from the requirements of this credit as emergency exits or non-regularly used/available building entries.
I am working on a project where the design scheme follows las described below.
There are ERU’s which supplies the fresh air to AHU’s and FCU’s in the project. These AHU’s and FCU’s will take the fresh and will mix with the return air to serve the rooms.
1. With this arrangement do I need to consider MERVMinimum efficiency reporting value. 13 filter in all my AHU’s FCU’s and ERU’s to comply with the credit requirement?
2. LEED 2009 BD+C supplemental update says’ Particle filters or air cleaning devices shall be provided to clean the outdoor air at any location prior to its introduction to occupied spaces’ which means installing MERV 13 in the ERU’s which supply the fresh air in to the building alone is sufficient to meet the credit requirement. Am I correct?
3. Considering MERV13 in all the FCU’s is possible? I have not seen any such FCU’s with MERV13 filters.
4. LEED 2009 BD+C supplemental update says’ Clean air filtration media shall be installed in all air systems after completion of construction and prior to occupancy’. Prior to occupancy, if we provide MERV-13 in all the ERU’s and AHU’s and MERV-6 in all the FCU’s. will this comply the credit requirement?
5. In this, project, there are many rooms i.e. retail areas, storage rooms, Janitor rooms etc. which will be considered for the exhaust requirement. If I provide a single exhaust for all these rooms and throw the exhaust air out of the building without mixing with air from any other regularly occupied room’s will I comply with the requirement?
Your response will help me a lot.
As far as my memory goes, the bottom line is that you need to filter all air that you bring into the building from outside through MERV13 filters if that air can end up in an occupied space.
Is medical supply room or pharmacy or detox rooms or dirty linens rooms to be included in this calculation?
I always include soiled utility, but it's somewhat of a judgement call. I would make the decision based on whether there is anything volatile in the room that could end up in the air, either as a chemical, particulate, or a smell.
You may find ASHRAE-170, Ventilation of Heath Care Facilities, to be a useful standard. It recommends ventilation parameters for various health care functions. These parameters primarily address odor and infection control, but they may provide insight for handling IEQc5.
For example, the 2013 edition recommends that soiled linen and decontamination rooms be under negative pressure, with all room air exhausting directly outdoors. Therefore, if you determined that the contaminants in these rooms meet IEQc5’s criteria, you could enclose and exhaust these rooms to meet the credit requirements.
By contrast, ASHRAE-170 recommends that most types of pharmacies be under positive pressure, so IEQc5’s negative pressure differentials would be inappropriate. ASHRAE-170 sets no requirements for medication rooms, but I have seen other standards that treat them the same as pharmacies.
Some jurisdictions have adopted ASHRAE-170 or similar standards as Code. Check local regulations.
We have a building in the construction review response instance. We are responding every comment, but we want to get more points to achieve Silver Certification. One of the credits we are considering to attempt for is the IEQ-C5, but our building already is constructed so we would have to make some changes in the HVAC project and construction itself, for instance to change intake air filters to MERVMinimum efficiency reporting value. 13 and we will have to include some exhaust systems in some specific spaces as the credit asks for.
Is it possible, after construction submittal, to make this changes and earn the credit?,
You can apply for a new credit after the first construction review. However, this one could be challenging. It has a lot of parts, as you know, so you would need to make sure that you meet each requirement. It could also be expensive if you need to add exhaust, deck to deck partitions and self-closing doors, not to mention the MERVMinimum efficiency reporting value. 13 filter banks. If you don't meet all of the requirements on the first try, I believe that you would need to file an appeal if you still want the credit.
I agree with Helen that this might be a challenging credit to do after the fact. Keep in mind that the addition of MERVMinimum efficiency reporting value. filters, etc. may have a negative effect on your energy efficiency - so make sure you wouldn't lose any points in EAp2/EAc1 in an effort to gain a point somewhere else. If you haven't already looked into it, I would consider talking to the client about EAc6 Green Power. It wouldn't require any construction changes, and depending on how efficient your building is, can be less expensive than you may think.
Thank you Helen and Renee, I was thinking the same thing.
Our project is sewing factory we already provide entryway mate and Exhaust as required, VRF system is used for A/c
1.Is it enough to attend this credit
2. Is MERVMinimum efficiency reporting value. 13 Filter is mandatory to attend this credit
3.Kindly tell what are the things are mandatory to get this credit
Yes MERVMinimum efficiency reporting value. 13 filters are required. The other mandatory requirements may be found at http://www.leeduser.com/credit/NC-2009/IEQc5?page=0#lang-tab
I found this article regarding VRF and LEED, with the caveat that I am not endorsing it.
1.How we achieve this credit when we use VRF
2.Is there any alternate compliance path or 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 related to this issue
3.Other than MERVMinimum efficiency reporting value. 13 we do all other mandatory things listed in LEED
4.Kindly give some tips to get this credit
MervMinimum efficiency reporting value. 8 filters on the fan coil units. Merv 13 on your outside air unit or intakes. If you are ventilating by natural ventilation then your proabably can't get this credit. With a dedicated outside air unit this is easy.
Thank you for your support,
1.It is ok for A/c Areas and what we attend for Ventilated areas (mechanical Ventilation include fresh air, Exhaust,)
2.How we attend this credit with Evaporative cooling
Awaiting for your reply
Do all janitor closets on a project need to meet the requirements of the credit, or can you exempt some closets by having a policy of only storing cleaning supplies in certain designated rooms?
You may have a tough time making that argument. You would need to make a case that cleaners are not mixed or disposed of in that janitor closet. The bottom line is, is there potential exposure to occupants from activities in that room?
An earlier comment said that, "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. #10098 seems to be saying that, if your entry system is at the exterior &/or less than 10 feet long, you will need to write a darned good justification explaining how your alternative approach is every bit as good as (and better than) the prescribed 10-foot indoor system".
What about providing half of the walk-off on the exterior through a grate or scored paving for larger particulates that you never want entering the building, and the other half as a finishing area/mat to clean the particulates that were not already taken off just outside the entrance? This method is advocated by the Living Building Challenge and seems to make sense from both a maintenance and cleanliness point of view.
If provided with documentation of this half-exterior / half-interior walk-off system, would this justify the alternative approach for the #10098 exception?
It's worth a try with plenty of support including precedent with LBC. The worst that can happen is the reviewers could reject it. It sounds like you don't plan to put a 10' mat inside regardless.
Thanks for the reply, Michelle. Do you know of projects with alternative walk-off systems that have been granted this exception for reference?
I am not aware of any specific projects. Document any research that shows the benefit of a grate outside versus having a 10' entryway on the inside. Are you sure you can't install a 10' rollout mat on the inside and contract for weekly cleaning? Or a combination of grate and rollout mat indoors, I would is acceptable.
Yeah, it's not really an option for our project.
On a related note, do you have any guidance on how scored stone can act as a substitute for grating as a part of the walk-of distance? We have stone at our entry way and rather than inserting a grate would prefer to keep our material the same. Thanks again!
Go back to the credit intent, which is to source control fo indoor contaminants to prevent occupant exposure. 80% of contaminants, specifically particulates, come into a building from feet upon entry. You are clearly attempting something that departs significantly from the credit requirements. In this case I recommend you design the best possible solution that addresses the intent, fully justify how your solution meets the credit intent, and wait to see what the reviewers say. This argument will be much stronger if you find research, examples, or expert opions. Focus less on whether what you do will be acceptable to reviewers, and more on the best solution to protect building occupants.
Thanks for your comments! We are not attempting to depart from the credit requirements as they relate to keeping dirt out of a building and building air, which is the intent.
We are simply trying to understand the logic behind the method for achieving this result, as we have found varied recommendations for walk-off surfaces that deviate from LEED, such as those recommended by the Living Building Challenge (LBC) under their "Health and Happiness" petal. It's helpful to know what is/is not possible before bringing our recommendations to the client.
Thanks again, Michelle!
To use an alternate compliance path, LEEDonline requires a narrative to justify the approach. The first step to ANY such narrative should be to address WHY the prescribed approach is “not an option.” Next, describe the alternative used, and finally, provide “justification that this path meets the credit intent and requirements.” As Michelle suggests, provide research, empirical data, or other evidence comparing your strategy to the prescribed approach.
I have not sought this path, but I have used the outline above to draft “darned good” justifications for other credits.
If you choose to pursue an alternative approach, you may wish to submit a formal inquiry describing your proposal prior to implementation to confirm that it is acceptable.
To best understand LI#10098, read it in its entirety, as well as the related IEQc5 Rulings that it supersedes: http://www.usgbc.org/leed-interpretations?keys=10098. Recognize that LI#10098 applies only under extraordinary circumstances such as existing conditions that restrict the available space. (See the July 23 post farther down this page.) If your project has constraints that preclude the required mat, these may be your “WHY.”
The link above includes several older, more flexible rulings that once allowed configurations similar to what you describe. These strategies may still be acceptable if you first meet the “physical impediments” criteria in LI#10098.
Also at the link above, LI#6093 is an ancient Ruling, not applicable to LEED-2009, but it describes three criteria for evaluating entry systems that may still be relevant when comparing strategies. (Beware: Parts of this Ruling are seriously outdated.) LEEDv4 also emphasizes cleanability.
In our project, each janitor closet (only for the storage of cleaning equipment and common deterdent) is placed inside a restroom, occupying a toilet cubicle. As a result, janitor closets are not completely sealed, but we regard the whole restroom as a sealed space. The exhaust system of the restroom complies with the LEED requirement, and janitor closet shares the same exhaust system. We are wondering if this kind of situation can meet the requirement of IEQc5.
I'm not sure. If you are committed to this solution I would position the exhaust nearest to the chemicals, such that the airflow moves from the toilet to the area of higher potential contamination.
Two projects, we've received the following comment: "Note that 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. 10098 allows for a portion of the entryway system to be located outside of the building, if covered, but only when there are physical impediments to including the entire entryway system indoors; physical impediments are typically only considered valid for remodeled buildings."
Question: Where does the statement "...typically only considered valid for remodeled buildings" come from?
Perhaps it comes from "is thoroughly justified" in IE 10098. I'm not surprised by this comment. Exceptions are designed for instances where it really isn't possible to meet the credit requirement through design, but there is a work around that still meets the intent. The reviewers often have interpretations for common situations that aren't written explicitly in the rating system.
Our LEED project building has a large three floor basement parking (74900 ft2) with small enclosed lobbies (with self-closing doors) connecting occupants to the office floors above. The three floors are connected with two large ramps each taking up half of each floor space.
The two bottom basement floors are under ground and the top basement floor is on ground level with large openings to the outdoors, this is where the whole basement gets it ventilation. The top basement floor has offices with a self-closing door.
We have exhaust systems placed on the two bottom basement floors which provide an exhaust rate for the whole three floor basement that will exceed the LEED requirement of 0.50 cfm/ft2.
The issue that we have is how to prove or demonstrate a negative pressure with the small lobbies and offices on the top floor, as this basement space can almost be seen as a large volume that is not totally enclosed. The reference guide states “sufficiently exhaust each space where hazardous gases or chemical may be present or used to create negative pressure with respect to adjacent spaces when the doors to the room are closed”, except this basement garage isn’t a room and technically we can’t close the doors to this space.
Would anyone know how we would deal with this situation, or how we would show the differential pressure of this space if we want to target the IEQc5 credit?
We are working on a 8 story + Basement Courthouse in Northern California. We have a private parking garage in the basement with 21 parking spots just for the Judges. Since there are only a small number of people using this entry (max would be 21 but most days would be less), are we still require to have the 10' walk off mat? It is a private entrance used only by a few, so will that really be considered a regularly used entrance?
Once upon a time these entryways were called "high-volume" entrances. That language was changed to "regularly used" to get away from the implication that there was a minimum number of uses that triggered the requirement. In my opinion, if the judges regularly use this entrance, it must follow the credit requirements.
We are working on a project considering the use of ventless dryers. Has anyone ever used ventless dryers and had a problem complying with IEQc5?
I looked up this technology since I wasn't familiar with it. The reason these dryers are ventless is because there are no emissions released, so the credit intent is met. Therefore, it should be reasonable to assume you can get this credit approved if you sufficiently explain the technology in your submission under special circumstances.
We have a multi story underground parking structure that is exhausted with 26,000cfm P1, 32,000 cfm for P2 and P3. The exhaust fans run 24/7 and are controlled by a manual switch that is never turned off. Our calculations show that we far exceed the pressure for both categories however for levels P2 and P3 we do not meet the .5cfm per ft2. In order to meet the .5cfm per ft2 the exhaust fans would have to be almost 60,000 cfm, however this would greatly increase the pressure within the space to about 30. Is it possible to submit showing that we far exceed the pressure needed for the space yet not have the required .5cfm/ft2? Has anyone had any luck this way?
Our project is the renovation of a space that will be cleaned by an outside contractor. This contractor is being given one large room that will be both the staff break room and the materials storage. The storage room will contain typical cleaning products, which we have always considered "hazardous" per the requirements of this credit (the organization does require the contractor to use green cleaningGreen cleaning is the use of cleaning products and practices that have lower environmental impacts and more positive indoor air quality impacts than conventional products and practices. practices, per the typical ID credit / EBOMEBOM is an acronym for Existing Buildings: Operations & Maintenance, one of the LEED 2009 rating systems. credit requirements). Were this just a storage room, we would provide the 0.5 CFM / SF of exhaust and other required elements. And we intend to provide 0.5 CFM / SF of exhaust, full height walls and self-closing doors for this space as well.
However, with the room also serving as a break room space, is achievement of this credit even possible with this scenario?
Your instincts sound correct to me. We had a situation that was somewhat comparable on another project and did not achieve the credit.
I agree with Helen. The intent of the credit is to protect occupants. In order to meet the credit, I suggest keeping a closet within the break room that meets the separation requirements.
Are linen closets and dirty utility rooms required to have exhaust to meet this credit? I know laundry rooms are
I assume that you're asking this question relative to IEQc5? It depends on what's happening in those closets/rooms. If there's chemical mixing, they need exhaust; otherwise, they don't. My guess is that the linen closet doesn't need exhaust, but without knowing what the utility room is being used for, it's hard to say.
Catalina—Health regulations in many US jurisdictions require exhaust to maintain a negative pressure differential in soiled utility rooms in hospitals, surgery centers, nursing homes, and other healthcare occupancies. When this is required, it is usually for odor and infection control. Insofar as odors & germs are undesirable contaminants that negatively affect indoor air quality and occupant health, these rooms might be applicable toward IEQc5 even if chemical mixing does not occur.
Clean linen rooms are typically for clean and sterile goods. The same regulations mentioned above often require positive pressure in clean storerooms, so exhaust fans would be inappropriate.
From a LEED point of view, I agree with Helen as the credit intent is regarding the use of chemicals in those rooms. As for the medical planning, your project team will need to determine which year of the "Guidelines for Design and Construction of Hospitals and Outpatient Facilities" the project falls under, if your project is in the US. There is a subsection devoted to Rehab Hospitals.
I have always included soiled utility rooms on the list of rooms to comply with EQc5 requirements, but not clean linen. As the others stated, confirm that the the clean utility doesn't contain anything "hazardous."
I'm now working on a project under LEED certification which aims to pursue this credit.
This project has an external parking area (which is included in the LEED Boundary) above grade and external to the building and a naturally ventilated garage, located exactly below the parking area (same extension, 1 level below grade). The natural ventilation is provided by grids (according to the national fire regulation).
The garage below grade is connected to the building through a corridor.
The corridor is separated from the garage by means a vestibule, with deck-to-deck partition and double self closing doors.
May we assume to comply with the credit by creating an overpressure in the vestibule instead of the suggested negative pressure obtained by a strong exhaust from the garage area?
I would think so as long as the positive pressure is at least as the negative pressure would be if you had done it that way. Let's see what Dylan says.
Heads up for those working on LEED Canada NC 2009 projects, 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 872 ruled 5,000 pages per month as the definition limit for a convenience copier. Ruling provided 2012-06-08.
Hi all,I'm now working on a project under LEED certification that aims to achieve IEQc5.
Hazardous gas and chemical use areas are served by sprinkler system as a fire suppression system. If the the hard lid ceiling is drilled by the sprinkler's heads, can we assume that it is still able to demonstrate compliance with this credit?
I haven't run across this issue as a problem. As long as you can demonstrate, if asked, that the gaps around the sprinklers are sealed, you should be fine.
Thank you so much!
We have a project that includes a workshop/studio space. This space will be used to construct small boats and other projects related to the organization's purpose which is marine environmental studies. The shop opens directly to the outdoors and to the interior (main education spaces) as well. As the shop is a "dirty" environment to begin with, we are not providing a mat from the exterior to the shop but will place a mat at the entrance from the shop to the classroom.
The classroom also opens directly to the exterior as well as having the entrance to the shop. In another LEED comment, a contributor mentions walk-off mat carpet tiles. For our small project, it might make sense to install these "walk-off tiles" throughout the classroom space for aesthetic as well as practical reasons. Will this work and what sort of cleaning protocol would be required?
See 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. #10281 (and #10282) regarding carpet tiles as entry systems
I would consider the shop at "outside" since it is a "dirty" environment. As for cleaning I recommend following the criteria for a roll-out mat, i.e. maintained on a weekly basis by a contracted service organization, at a minimum for the 10' at the entry (outside to classroom; and shop to classroom) that is required for the credit.
We're wrestling with the walkoff mat requirement for a recreation center where there is an indoor/outdoor pool - one end of the pool and the roof retract during clement weather to provide an outdoor pool experience, yet the pool area is fully enclosed during cold weather. there is a concrete floored office and lifeguard lounge accessed only from the pool area, and swimmers all must walk through a locker room and shower before walking onto the pool deck. there is a small exterior zone outside of the pool enclosure surrounded by a fence and accessible only from the pool area. A strict reading of the credit requirements would have us placing walkoff mats everywhere, even in areas that are not accessible to the rest of the building which seems a bit odd. We have walkoff mats located at the two building entrances.
I believe you would be fine by just having the walk off mats at the main entrances. Your scenario would be similar to a building having an outside balcony were the occupants have already entered through the main entrance and some may or may not go out onto the balcony, which is not accessible to public traffic. Now if the occupants were going to a private exterior courtyard or playground, areas with dirt and debris, a walk off mat would be needed.
It is about removing dirt from your shoes and not bringing it into the building. Occupants using the pool are not going to be walking in the dirt or public sidewalks and whatever else.
I concur with Todd.
Can someone please explain what exactly is meant by a dedicated exhaust system?
Also - are the self closing doors a requirement or an option? (The reference guide sais this is optional).
I'll let Dylan confirm, but here is how I have always interpreted these requirements:
1. Dedicated exhaust goes directly outside with no opportunity for recirculation. It's ok to be on same exhaust run as toilets.
2. I've always considered self-closing doors as a requirement. There used to be a checkbox on the form. Since it's not there in the 2009 form, and if the reference guide says it's optional, I would go with that, as long as you can document separation and the pressure differential.
The Green Facilitator
Specifying and sizing equipment with MERV 13 filters affects both these credits.
If ventilation systems are to be used for building flush-out, they need to be sized to meet the air volume requirements of IEQc3.2 and must be compatible with MERV 13 filtration.
MERV 13 filters will increase fan energy demand as higher filtration ratings increase resistance to airflow and therefore slightly increase your energy demand.
Mechanical systems components will need to be commissioned to confirm appropriate installation of filtration media.
Additional mechanical system capacity may help meet the requirements of IEQp1. Ventilation systems must have MERV 13 filtration on all supply air.
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.
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