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Baseline for outdoor air ventilation
This prerequisite establishes a baseline for providing a minimum amount of outdoor air to buildings in order to maintain good indoor air quality and keep occupants comfortable and healthy. The prerequisite references ASHRAE 62.1-2007 (with errata but without addenda) and is often more stringent than local building codes, although it is not likely to entail any added costs.
Two cases, and you might need them both
The compliance paths for mechanically ventilated and naturally ventilated spaces, Case 1 and Case 2, are somewhat different and you may need to follow both paths for the same building. Naturally ventilated spaces must follow the distinct requirements set out in Case 2, even if other spaces in the same building are mechanically ventilated and are following Case 1...
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52 Comments
Mini Split System
I have a 400 sq ft office in an existing building without an existing A/C system. We installed a mini split system (no outside air) for mechanical conditioning, and there are 2 existing windows but are usually closed. What is the best approach for complying with this prerequisite? Can the mechanical approach be used if the equipment doesn't have an outside air intake? Or should I take the natural ventilation approach? Thanks!
LEED CS v2009 certified building
Hi all,
We have a small LEED:CI project in a CS certified shopping mall. We don't have any direct outdoor air intakes, we take the air from the main atrium and give it to our space. The base building has even achieved increased ventilation credit by natural ventilation, so air in atrium is quite acceptable.
How can we document compliance with this prerequiste?
Thank you!
No Engineer on Project
All HVAC mechanical systems were existing. Only the ductwork was installed. There is Engineer for this project is there a way to comply without the signature?
All HVAC mechanical systems were existing. Only the ductwork was installed. There isnt an Engineer for this project is there a way to copmly without the signature
Technical Rooms
Does technical rooms, as IDFs rooms needs to have outside air renovation? As it is not intended for human occupancy, we understand that it is not necessary to consider these kind of rooms as a project zone. Is that correct?
Thanks,
Juliana
VRP Compliance Calculator
We have a CI project with multiple zone units and 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. system. We are using template VRP compliance calculator. For filling it, there are no instructions on the template or in ASHRAE on what "Vdzd" means. 62MZ Calc, states that Vdzd is the "Design total supply to zone (primary plus local recirculated)". The Refence Guide states that "for VAV systems, Vpz is the minimum expected primary airflow for design purposes", and we understand that these statements are conflicting. Wich volume is correct to consider? It seems that the VRP calculator already takes in consideration the Vpz minimum airflow. Is this correct?
In the VRP calculator we are using the total supply air in the zone as described for Vdzd, and considering Ds as 100%. Is that correct?
Thank you,
Juliana
Ds should be adjusted to consider the heating design flow rate, which will usually be significantly less than the cooling design flow rate. Vdzd is the total supply air.
Local Code
Does anyone know if for ventilation requirements Title 24 - 2005 is acceptable in lieu of ASHRAE 62.1-2007? I know for EAc1 Title 24 - 2005 is seen as equivalent to ASHRAE 90.1- 2007. Additionally, it is written in the book that "local code can be used in lieu of ASHRAE when the local code is more stringent."
This one is challenging to answer, because T24-2005 doesn't include the same procedures as ASHRAE 62.1 for multi-zone recirculating systems (e.g. 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.). If you're working with a dedicated outdoor air system and the effective airflow rates are greater per person than ASHRAE 62.1, then I think it's fine to use T24.
Min Airflow in Intermittent Occupancy Spaces
We received a comment back on a CI project stating:
"Demonstrate the system serving the special occupancy space is capable of modulating system and zone minimum supply volume below 0.30 cubic feet per minute per square foot of supply volume."
It then goes on to say:
"Confirm the mandatory requirements of ASHRAE 90.1-2007 and ASHRAE 62.1-2007 are met."
The ASHRAE 62.1-2007 calculation uses the minimum expected primary airflow. Now that there is a requirement to reduce the min airflow in this intermittently occupied space to 0.3 cfm/sf, the minimum expected airflow no longer meets the requirements of ASHRAE 62.1-2007. The purpose of ASHRAE 62.1 is to provide indoor air quality that is acceptable to human occupants. Here I seem to be getting penalized for not providing enough air to a space that is unoccupied.
I do not want to submit the 62.1 calc for IEQp1 at the minimum expected occupied design conditions to have the reviewer look at my schedule and see the 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. box min value (which has been set lower due to the intermittent unoccupied conditions) was not used, but I do not see a place in the IEQp1 form to note that this space has intermittent occupancy (the diversity variable is only applied at a system level, not per zone)
Rick, I've never seen a requirement specifically in ASHRAE 62.1 to modulate down to 0.3 cfm/sf. Is this a project specific requirement? Even an intermittently occupied space benefits from ventilation to combat off-gassing of materials within the space. I would provide a detailed response narrative, rather than trying to adjust the form to accommodate a specific condition.
Calculating Vot in Credit Template
The Template calculates Vot by dividing Voz by Ev. ASHRAE 62.1 2007 arrives at Vot by dividing Vou by Ev, not Voz. This matters because Voz has already been corrected to account for the zone air distribution effiectiveness where Vou has not. This results in Vot being much higher than anticipated. Is this a known error in the credit template that I can simply bypass by asking for the most recent update of the template? Has anybody else ran into this error?
I should note that this is a multizone recirculating system.
System serving new and exisitng spaces
In the reference book, under IEQc1 point 4. Implementation, it states that "This prerequisite is not limited to the project scope of work." Could someone please clarify exactly what this is referring to?
It refers to the building HVAC system supplying enough air, and also location of air intakes within this paragraph.
Currently I have a new system that is serving spaces that fall under the LEED scope, and spaces that do not. Do all spaces need to be included for compliance since the Ventilation Rate Procedure looks at both individual spaces, and the system as a whole? While spaces outside of the scope wouldn't count towards the credit, they could change the system ventilation efficiency.
Does anyone have an experience with this?
Michelle, you'll have to consider all spaces associated with the HVAC system, in order to determine the proper ventilation efficiency (Ev), as you mention. The main purpose of the comment in the reference book is that even if base building systems are outside of project scope, the project still needs to comply with ASHRAE 62.
System vs. Zone Compliance
Is it the system or the zone that must comply with the ventilation requirements?
In May 2011 the USGBC updated the calculator for v2 projects (v3 doesn't appear to be updated) to check for compliance only at the system level... Our previous understanding was that each zone has to meet the thresholds for credit compliance (EQp1 = equal or better, EQc2 = 30% higher or better), but the new calculator only requests OA flow at the system level and then on a separate sheet only examines the system for compliance, not each individual zone.
My understanding of this is that each zone has to comply.
Zones for a small CI 2.0 Project
We have an office project (LEED CI 2.0) in an exsitng small building about 3500 s.f. The building is served by one existing central system that provides OA to the space. The layout of the space is very open, almost no doors, the second floor is a mezzanine that is open to the first. Basically all the outdoor air coming in is shared between spaces due to transfer and openness,etc. In addition there are two very large ceiling fans that circulate air throughout the open space. Although there are different "spaces" designated (open office, coffee area, materials storage, etc.) it doesn't seem appropriate to analyize these separately as "zones" for this credit due to the open nature of the plan. Would it be possible to analyze the space at the building level as one "zone?"
Greg, could you provide more detail on how the OA is brought into the space? Are there multiple injection points?
Roger,
The OA comes into the space through multiple points. I'd estmate about 30 or so dispersed throughout the building(a combination of floor grills and ceiling diffusersIn an HVAC context, diffusers disperse heating, cooling, or ventilation air as it enters a room, ideally preventing uncomfortable direct currents and in many cases, reducing energy costs and improving indoor air quality (IAQ). In light fixtures, diffusers filter and disperse light.).
Thanks.
Greg, you should be fine treating the space as one zone, given your description of the OA distribution.
Online Template Issue - Upload Time Required for IEQp1
I have a technical question about LEED Online and inputting information into the Adobe Form for IEQp1. The issue I am having is the amount of time required to document a building that has several zones.
Currently, the only way I know how to document IEQp1 is to actively enter each zone, line by line online. However, each time I input a value, the whole form pauses and I believe, re-calculates every value in the table. This pause greatly slows the process of inputting information and for buildings with well over 40 zones can increase our documentation time by several hours.
Has anyone run into this issue with online documentation and found a better method? Are there ways to download and then upload adobe templates with LEED Online v3? Or any other process that I might try? Thanks.
Shannon, see response from Kimberly below. I recommend using a spreadsheet approach for projects with more than 25 zones. Make sure that you have all of the data from the LEED template in your spreadsheet, at minimum. It can be helpful to also submit the formal ASHRAE developed 62 calculation spreadsheet as a separate check of compliance.
CI IEQ p1 - Template Table
Do we have to use the template table or can we upload our own spreadsheet using the same calcs? The template spreadsheet takes much more time than our spreadsheet that is used during the design phase.
If you are uploading your own spreadsheet, make sure you still include the information required in the template (i.e. for each ventilation zone, the amount of outside air required by ASHRAE 62.1-2007 and the actual amount of outside air provided to that zone). Just showing the outside air volume required and provided on a system level (per air handling unit) for multi-zone systems is not sufficient.
Completing OA table with correct Ev value.
ASHRAE 62's Ev value is determined by either the ASHRAE Standard 62 Appendix A (lowest calculated method value of the zone efficiency Evz) or per ASHRAE's Table 6-3 "System Ventilation Efficiency". The Ez method deteremined from these methods are used as a system Value is determined from the space airflow fractions... However, the LEED Online "Ventilation Rate Procedure" Table appears to divide HVAC units into spaces covered by the unit and the Ez value for each space is required. Should the values entered in this table be entered by each space (each having it's own Ez), or should the calculated system Ez value be used for each space?
Are you still looking for help with this question? It's been a tough one to answer but I'll keep trying to find help if you need it.
ASHRAE 62.1-2007 section 4
According to this section, a local survey is needed to document the local air quality. But even the GBCI refers to the ventilation rate procedure when we ask for clarification, and the form/uploads do not require a outside air quality measurement. Does anyone know why section 4 is mentioned in the prerequisite if the rate procedure is required?
Gerrit.Jan, there is no upload for the ASHRAE-compliance, but in the form of IEQp1 the "Ventilations Systems Designer" needs to sign this compliance with his initials.
We are currently discussing this issue for- and backwards: Does anyone have experiences with section 4 "Outdoor Air Quality" in LEED projects outside the US? If the air analyses and classifications required by ASHRAE are not available in a country - would that exclude the project from certification?
4.1 Requires a site classification: "attainment" or "non-attainment".
The standard does not require any classification for confomance, it simply requires it to be classified. Areas with no EPA compliance status designation shall be considered "attainment" areas. This must surely count for all international areas.
4.2 Requires a general visual and smell observation site survey during normal building occupation times.
4.3 Requires a short report on 4.2 and 4.1.
This section should in no way hamper certification. It should only clarify things like that it was observed in the planning not to go pointing the outdoor air grill in the direction of car exhaust gas, etc.
We found out that air quality measurements are available on the internet, not specific for our location, but at a representative location nearby. For our project(s) in Amsterdam, it appears that all levels are fine. This is a good starting point, no additional filter types are needed in the existing ventilation system. A visual and smell survey is expected to be performed within a few days by our engineers, but we do not expect problems by that.
Jean:
ASHRAE 62.1-2007 ch. 4.1 says
"IN THE UNITED STATES, areas with no EPA compliance status designation shall be considered "attainment" areas ".
To me this sounds like "outside the US the attainment for each pollutant shown in Table 4-1 has to be determined (e.g. by measurement)."
Since the CI-Reference Guide IEQp1 ch. 4 recommends to evaluate the planned location of the project PRIOR TO leasing or acquistion, this i.m.o. can lead to a failure of the prerequisite!
Any opinions on that?
My interpretation of a recommendation is that it is not a requirement. The mail goal is of this part of the prerequisite to provide a descent level of indoor air quality to the building occupants. The prescribed survey of the actual air quality is a good method to detemermine adjustments if needed, and to confirm that the AHU1.Air-handling units (AHUs) are mechanical indirect heating, ventilating, or air-conditioning systems in which the air is treated or handled by equipment located outside the rooms served, usually at a central location, and conveyed to and from the rooms by a fan and a system of distributing ducts. (NEEB, 1997 edition) 2.A type of heating and/or cooling distribution equipment that channels warm or cool air to different parts of a building. This process of channeling the conditioned air often involves drawing air over heating or cooling coils and forcing it from a central location through ducts or air-handling units. Air-handling units are hidden in the walls or ceilings, where they use steam or hot water to heat, or chilled water to cool the air inside the ductwork.'s are equiped with right components. The reference to the ASHRAE standards is always focused on the US situation, and abroad situations should always try to find a workaround (as good as possible). Does anyone have experience in using a alternative compliance path or the "special circumstances" option on this prerequisite?
CI V3 - IEQp1 Uploads
IEQp1 Upload # 6 - "Provide the regulatory approval letter or document indicating the engineered system has been approved by the authority having jurisdiction."
Will approved building department permit application satisfy this requirement?
Malik, upload #6 is meant to apply more to naturally ventilated buildings where computational fluid dynamics of multi-nodal airflow modeling is used to validate a design that would otherwise not meet prescriptive mechanical ventilation requirements. A building permit would be acceptable, but I would make sure someone actually reviewed the ventilation data submitted. Depending on jurisdiction, ventilation data is only given a cursory review.
Thank you for your reply.
CI V3 - IEQp1 Uploads
IEQp1 Upload # 3 - "Provide a graphic and numeric summary of the airflow analysis performed. Include the boundary conditions used for the analysis; simulation algorithm; solution variables; temperatures; airflow volumes and mean age of air for the spaces modeled".
If mechanical floor plan indicating ductwork, diffusersIn an HVAC context, diffusers disperse heating, cooling, or ventilation air as it enters a room, ideally preventing uncomfortable direct currents and in many cases, reducing energy costs and improving indoor air quality (IAQ). In light fixtures, diffusers filter and disperse light., thermostats, etc. is provided as an upload, will that satisfy the above upload requiement # 3?
Malik,
Is your space naturally ventilated? Upload #3 doesn't apply to mechanically ventilated spaces.
Thank you for your reply.
Must C&S HVAC certified under 62.1-2004 upgrade to 2007 for CI?
If a CI project is being built out in a building that is certified under Core and Shell to meet ASHRAE 62.1-2004, does this prerequisite require that all spaces within the scope of the TI meet 62..1-2007, even if the base building HVAC is outside the scope of the TI?
David,
The TI spaces need to meet 62.1-2007. A plus: the ventilation rates are the same for most space types between the 2004 and 2007 versions. You do have to be careful to show compliance with 2007 on a space by space basis within the TI area. Some designers run into problems when TI spaces have a high proportion of densely occupied areas (like conference rooms) and the CS HVAC system only accounted for an open plan office, for example.
ISSUE Part 2
This is taken from ASHRAE 62.1 2007 USERS MANUAL, Page 93
Example 6-E—Occasionally Occupied SpacesOccupied Spaces are defined as enclosed spaces that can accommodate human activities. Occupied spaces are further classified as regularly occupied or non-regularly occupied spaces based on the duration of the occupancy, individual or multi-occupant based on the quantity of occupants, and densely or non-densely occupied spaces based upon the concentration of occupants in the space.
Q
Table 6-1 lists ventilation requirements for infrequently
occupied spaces such as electrical rooms, elevator machine rooms, and corridors. Do all such spaces need to be ventilated to meet Standard 62.1?
A
No. Only "occupiable spaces" are required by the Standard to be ventilated. By definition, this excludes "those spaces intended primarily for other purposes, such as storage rooms and equipment rooms, that are only occupied occasionally and for short periods of time." So if an equipment room, for example, is expected to be occupied only
occasionally (e.g. for servicing equipment), ventilation is not required by the Standard (although it may be required for other reasons such as temperature control). Similarly, stairs and corridors that are used primarily for emergency egress do not have to be ventilated. Corridors that are more frequently occupied, such as those used for the delivery of merchandise in a retail mall, must be ventilated.
SO....would the refrigeration / Freezer section be considered a "storage room"
Elizabeth,
If the team can show that the freezer is occupied only occasionally, then we would think that it follows the ASHRAE response for storage rooms and does not need to meet ventilation requirements.
However, if the cooler is more of a workspace then the team would need to find a solution to meet the ASHRAE requirements.
Thanks Ben, A freezer is in essence a HVAC system, correct? Additionally, the ventilation of a freezer would cause huge increases in the energy consumptions based upon size, reconditionling the air and dehumidifying. Seems that a freezer would not apply, even if it is a workspace. Imagine the energy consumption.
This was a problem for supermarkets during the LEED for retail pilot. How do we find out what they decided?
We have kicked this question back and forth in our office. We have done some work on LEED for Retail - specifically Hannaford's LEED Platinum store - and we did not have any freezers that were work spaces.. so yes, they were "storage".... so it comes around, in our opinion only, that if a freezer DOES have people working in it on a regular basis, we think it needs to be included in your calcs. There are some very smart ventilation systems and efficiencies in refrigeration that would help the energy optimization calcs. Ultimately, it may need to be a call by the GBCI based on your specific case.
Thanks Gunnar. What was the sqft of the freezers? How did you determine it was not a work space? Anything would help...
In the grocery store, refrigerated prep areas such as the meat cooler (450 sq ft) where there are tables for cutting and processing meat are ventilated. On the other hand, the grocery freezer (400 sq.ft.) which is essentially a large walk refrigerator is not ventilated because it is used like a closet (or refrigerator), only entered occasionally and not where an employee is working.
Issue -
Would the refrigeration/ freezer section of a food distribution warehouse have to meet this / be ventalated? The sq footage of this section is 82,000 square feet.
The areas woulld be ill affected through increased humidity and temperatue. Energy would be wasted based increased need for defrost.
CI IEQ p1 ASHRAE 62.1-2007 calculator
Does anyone know where I can get a ASHRAE 62.1-2007 calculator to figure the CI IEQ p1. The LEED on line credit page is asking for it.
If you're using LEED online v3, you'll need to sign in and click on IEQp1. Once you're in the credit page, look over to the left side of the page and there will be a box that says "Credit Resources" click "more" and you will see a link for the calculator in excel.
IEQ and related products
Wondering why the Related products such as bamboo floor, access flooring, fabrics etc are in this section instead of MR.
Jill, our Related Products feature is very much a part of the site that is still in "beta." We are in the process of updating our mapping of GreenSpec-listed products to LEED credits. Thanks for asking, and check back again in the next few weeks as this changes.
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