CI-2009 IEQc6.2: Controllability of Systems—Thermal Comfort

  • NC CS Schools EQc6.2 Thermal Comfort Diagram

  • What you need

    All multi-occupant spacesConference rooms, classrooms and other indoor spaces used as a place of congregation for presentations, trainings, etc. Individuals using these spaces share the lighting and temperature controls and they should have, at a minimum, a separate zone with accessible thermostat and an air-flow control. Group multi-occupant spaces do not include open office plans that contain individual workstations. (like classrooms or auditoriums) must have at least one occupant comfort control. Multifamily housing must also have one control per unit.

    For individual spaces or open-plan offices, at least 50% of occupants must be able to control their individual comfort conditions.

    A lot of options

    Providing thermal comfort control with operable windows is a common way to earn this credit.Providing thermal comfort control with operable windows is a common way to earn this credit.The credit defines comfort according to the four primary comfort criteriaComfort criteria are specific design conditions that take into account temperature, humidity, air speed, outdoor temperature, outdoor humidity, seasonal clothing, and expected activity. (ASHRAE 55–2004) identified by ASHRAE 55-2004:

    • air temperature
    • radiant temperature
    • humidity
    • air speed.

    A comfort control meeting the credit requirements needs to only address one of these four. Common ways to meet the credit include installing:

    • heating radiators or radiant panels with individual temperature controls;
    • operable windows;
    • or adjustable local air 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..

    Are desk fans allowed?

    Is a desk fan an acceptable strategy? Some project teams have reported success with desk fans, but it may depend on your rating system.

    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. #1722, 3/22/2007 which applies to NC-v2.2, but not officially to LEED 2009, states that they are not allowed, since the intent of the credit "deals with providing thermal comfort control as an integral part of the building design."

    However, Reference Guide Addendum ID# 100000766, 2/2/2011, explicitly applies to LEED-2009 rating systems, and states that "Individual comfort plug-in devices are acceptable for meeting the intent of this credit" as long as they are included in your EAp2 energy model.

    Choosing your ventilation system

    You can meet this credit with either naturally or mechanically ventilated buildings.

    Projects using natural ventilation need to provide access to operable windows for at least 50% of occupants. Access to an operable window means that an occupant's desk is located within 20 feet of a window to the inside, and ten feet from side to side.

    Thermal comfort controls like thermostats are a common way to earn this credit, but make sure you choose a mechanical system that allows for that level of variability.Thermal comfort controls like thermostats are a common way to earn this credit, but make sure you choose a mechanical system that allows for that level of variability.It is more difficult to achieve credit compliance with mechanical systems like forced air because the controls typically serve a large area. You can provide a greater level of thermal comfort with underfloor air distribution that provide easily controlled diffusers. 

    For constant-air-volume systems that do not allow individual control, you may need to add an additional unit, such as a reheating coil at the diffuser or perimeter baseboard heating, to achieve the credit’s intent. 

    Heating or cooling

    For mechanically ventilated spaces, previous LEED-certified projects have complied with the credit by providing occupant controls for heating or cooling only. For example, a building providing controls that adjust heat within a certain temperature range can comply with the credit, even if controls are not provided for the cooling season. 

    Air diffusers provided via underfloor air distribution systems can provide individual comfort control in offices.Air diffusers provided via underfloor air distribution systems can provide individual comfort control in offices.

    Approaching the credit by building type

    Multifamily: For a small unit, you may only need a single control—it can be a window or a thermostat. Most units will require a control in each bedroom and in the living room or other multi-occupant spaces.

    Offices: Private offices and open space offices need multiple controls for 50% of occupants. One control in each conference or meeting room.

  • About the IEQ space matrix

    The IEQ space matrix is a key reference document for this credit (as well as several other LEED credits). Currently in its third edition as of 4/1/2013, the matrix is a spreadsheet that categorizes the spaces from the IES Lighting Handbook, 10th Edition for applicability to IEQ credits. These lists are intended to be used along with key LEED definitions for spaces such as 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.. Many questions about this credit can be clarified by reviewing the IEQ space matrix.

    FAQs for IEQc6.2

    In some areas, individual fan coil units can be adjusted through the BMS, which can be accomplished by the occupant phoning the building manager. As each unit can be controlled, is this sufficient for occupant controllability? A benefit is that the BMS can reset the system at the end of a day and enable the whole system to be balanced.

    It's a good idea but the implementation may not work as well as original conceived. For instance, what if the building manager isn't always readily available? Does everyone have access to his or her number? How many adjustments are possible within your open plan office area? Would there be enough distinct settings to account for controls for roughly half of the occupants in this space?

    LEEDuser is aware of one project earning the credit by providing a very detailed narrative. Clearly visible postings were made in the building that helped to clearly communicate the process to the occupants and a phone number was provided for the occupants so that they would have quick access to the manager.

    Until 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. clarifies this issue, it is likely to depend on specific circumstances. The strategy makes sense from an energy efficiency standpoint, but the intent of this credit is more about individual occupants having comfort controls.

    Do I have to include all individual and multi-occupant spaces and do they have to be consistent across IEQc6.1 and IEQc6.2?

    In short, yes. If IEQc6.1 and IEQc6.2 are both pursued then all individual and multi-occupant spaces must be included. LEED reviewers will want to see consistency across these for IEQc6.1 and IEQc6.2.

    I’m working on a project that has transient occupants. How does the IEQ space matrix address transients, and are transients required to have access to the controls?

    The matrix includes several space types that have transient occupants, for example: libraries, auditoriums, and transportation terminals. Controls must be provided for these spaces if they are listed as individual occupant or multi occupant and have the corresponding "Yes" in the relevant credit column.

    This question is addressed in more detail under IEQc6.1.

    The categories given in the IEQ space matrix don’t really fit how some of the rooms in my project will be used. What should I do?

    Use your best judgment. The matrix states, “exceptions to area use classifications will be accepted on a case-by-case basis for spaces with atypical uses or those in which strategies required for compliance may compromise the function of the space. This is not an exhaustive list.  If a space is not listed, project teams should try to find a similar space type and follow that guidance.”

    Safety and code compliance have to always come first. You can always try writing a strong narrative to make your case for your project’s exception. However, it’s important to keep in mind that some project types may simply not be well aligned with the credit’s requirements. In that case, it might best to focus your efforts on other LEED credits that are more applicable.

Legend

  • Best Practices
  • Gotcha
  • Action Steps
  • Cost Tip

Pre-Design

Expand All

  • Early during pre-design the owner identifies occupant comfort and control goals in the Owner's Project Requirements for commissioning in EAp1 and EAc3.

  • Assess your climate and your ability to provide occupant-controlled interventions for different comfort criteria. These may include: 

    • operable windows for air speed and temperature
    • air conditioning for temperature and humidity 
    • ceiling fans for air speed
    • desiccant dehumidification 
    • radiators for air temperature
    • air diffusers for air speed.

    Desk fans are not considered an acceptable strategy according to LEED Interpretation #1722, although USGBC has not officailly applied that Interpretation to LEED-2009 rating systems.

  • For commercial buildings, systems like fan coils paired with dedicated outdoor air systems can help provide local control to occupants, while reducing first-cost expenses like duct-work.

  • Operable windowIncluding operable windows in the building can reduce dependence on specific mechanical system designs. Positioning as many occupant spaces near operable windows as possible can make this credit easier to achieve.

  • Some conventional systems typically rely on central control, and multiple controls may be difficult to incorporate. Underfloor air distribution, on the other hand, is designed for flexibility and individual control in a way that naturally supports this credit. 

  • The required comfort control has to address only one of the four primary comfort criteria identified by ASHRAE 55-2004: air temperature, radiant temperature, humidity or air speed. You may address multiple criteria, but aren’t required to do so.

  • The comfort system does not have to be especially expensive or complex. It may simply be, for example, localized air conditioning with occupant controls. 

  • Providing occupant comfort controls can add some costs, but they can also save money and improve occupant comfort and productivity. Occupant comfort controls allow for the mechanical system to respond to conditions specific to different parts of the building, improving overall comfort while saving energy. Typically, a system under central control is sized and calibrated for the least comfortable space. For example, in cooling season overhead air conditioning is provided for the warmest space, while everyone else under the same AHU feels uncomfortably cold. By providing individual controls, everyone can adjust the cooling or air speed to their comfort needs. This control often directly translates to lower energy costs.  

  • Individual thermal comfort plug-in devices are allowed under IEQc6.2, as long as they are included in the design but not the baseline energy model.

Schematic Design

Expand All

  • Develop a list and number of all occupied spaces in the building, noting multi-occupant spaces. The number of individual occupant spaces and multi-occupant spaces should be the same between IEQc6.1 and IEQc6.2.

  • A multi-occupant space is space for group interactions, like classrooms, conference rooms, cafeterias, lobbies, warehouse loading areas, theaters, break rooms, commercial kitchens, retail stores, and exhibit spaces that expect large number of people to gather. 

  • Each multi-occupant space should have at least one comfort control that regulates air temperature, radiant temperature, humidity, or air speed in that room. 

  • For individually occupied spaces, identify the total number of workstations anticipated to be in each space per the project FTE count or based on the estimates listed in the Reference Guide Appendix 1. "Workstations" are referred here as places where full-time occupants spend majority of their time.

  • How many people per operable window? If using operable windows, locate as many people as possible close to them. Although strictly speaking it may make sense to count one person as needing one operable window, the experience of the LEEDuser team is that the credit has been approved by counting multiple people sitting close to a window as long as a person is within a 20-foot depth and a 10-foot length from one. The operable portion of the window must also be at least 4% of the size of the floor area of the space accessible to a given window, per ASHRAE 62.1-2007. For example, for a 5-foot-long window plus 10 feet on either side the total qualifying floor area would be 25 (5 + 10 + 10) multiplied by 20, or 500 ft2. At 4% of the floor area, the operable window area must be at least 20 ft2. Refer to the Documentation Toolkit for a diagrammatic representation of the window-area-to-floor-area relationship.

  • How many people per control? Even though the credit calls for individual comfort controls, projects often earn this credit by grouping occupants around a single operable window. Similarly, a single mechanical system control can serve up to two occupants, contributing to the 50% credit threshold.

  • If less than 50% of occupants have access to operable windows, add more operable windows, adjust the layout, or add ducts, baseboards or diffusers with controls to add individual comfort controls. Run calculations again and redesign till 50% of people have access to the controls. 

  • An open office space is individually occupied where each person has an individual desk and defined space. 

  • Individually occupied spaces are defined as the place where an occupant spends most of their time, such as a private office, reception desk, workstations or cubicles in open-plan offices. 

  • A control can be as simple as a switch to turn air conditioning on or off, changing temperature in a small permitted range using a thermostat, or closing a diffuser to reduce air flow. 

  • Providing comfort controls that allow an occupant to turn a system on only when using the space, and turn it off at other times, supports energy efficiency goals. Whether or not it can contributes to demonstrable energy reductions for EAc1: Optimize Energy Performance is another question. Except for operable windows, this would be difficult to demonstrate.  

  • Note the credit requirement is based on number of occupants for individually occupied and number of spaces for multi-occupants. Only half of the total building occupants must have controls in individually occupied spaces. However, each of the multi-occupant spaces must have independent controls. 

  • For example, an open plan office has 100 desks and 10 private offices, for a total of 110 individually occupied spaces. At least 55 of the people occupying those spaces must have access to comfort controls. The same office also has two conference rooms. Both conference rooms need their own controls. 

  • Facilities managers may have reservations about providing controls to users. The range of control can be limited to a certain range, however, and should be programmed to be reset at least at the end of the day with the building’s typical temperature setback. Be sure that occupants will be educated on how to use controls. 

  • Additional controls imply higher construction costs, with additional wiring, and maintenance for uninterrupted operations. There are low-cost options, such as baseboard heating radiators and heat pumps that are easy to operate and provide good local comfort. Compare the upfront costs of better controls to the long-term benefits of higher productivity, better test scores or hotel occupancy, plus savings in energy usage.

  • Underfloor air or ceiling-air plenum are common systems for allowing occupant comfort control. In addition, they can: 

    • allow for flexibility in layout and design, and ease of electrical wiring, installation of work stations, and arrangement of work spaces; 
    • realize first-cost savings in reduced duct work, lower floor height and possible an additional floor with more leasable space;
    • and enhance daylighting by creating higher floor-to-ceiling heights.

  • In the absence of operable windows, it is difficult to meet the 50% credit requirement unless the mechanical system is designed with zones to provide multiple comfort controls. 

  • Operable windows, although offering some energy and comfort benefits, have some drawbacks. They allow in outside air, which may not be of the highest quality, and also allow in outside noise. The unconditioned air they allow in can affect the operation of mechanical systems. 

  • Operable windows are generally higher in cost than fixed windows.

  • A mechanical system with more individual controls may cost more than a conventional system. This cost can be offset, though, by lower operating costs, a more flexible layout, and improved occupant productivity. 

Design Development

Expand All

  • If using a mechanical system, confirm that the project design is progressing with a system that allows for multiple controls.

  • Update the count of total individual workstations and those with controls. If the controls do not add to be 50% of total workstations then investigate the potential to add more controls or change the layout to make them more accessible to windows. 

  • Configure the mechanical system so that when windows are open, cooling is turned off to avoid wasting energy. You can accomplish this by hooking operable windows up to wireless sensors that communicate with the cooling system. 

  • Install a building management system that communicates with occupants to open operable windows when outside temperature and humidity are within comfort range as defined by ASHRAE 55-2004. 

Construction Documents

Expand All

  • If using operable windows, make sure the window schedule and all construction drawings include relevant details. Specify windows and window locations that make them easy to operate. 

  • Provide for the commissioning of control and response systems in the commissioning scope for EAp1. 

  • During the construction bidding phase, discuss the schedule to make sure correct control equipment is purchased and installed on time. The controls are only as good as the feedback and response system they are connected to. Explain the control sequence to the subcontractors to minimize confusion. 

  • If value engineering threatens comfort controls, remember their benefits—including energy savings and higher productivity.

Construction

Expand All

  • Ensure correct installation of all mechanical systems. 

  • List all spaces and occupancy types for the project on LEED Online. Mark the kind and number of controls available in each of those spaces. Select “None” if any of those occupants do not have individual controls. The online submittal form will automatically advise on number of required occupants with controls and those that are available. 

  • The commissioning agent should check and verify operation and setpoints of the controls. (See EAp1.)

Operations & Maintenance

Expand All

  • Educate occupants about the range of control adjustments available. Many air diffusers can open or close the air vent and change the temperature only within a limited range, typically within 5ºF–10ºF of acceptable comfort levels. For example, a heating system may allow a range from 68ºF–74ºF. Comfort controls may not allow larger changes or switching to air conditioning during the heating season, and it is helpful for occupants to understand this. Encourage occupants not to leave windows open when heating or cooling is on.

  • Train operations and maintenance staff to troubleshoot any problems, particularly if there is a BMS system that responds to user controls, with overrides for end-of-day setbacks.

  • Incorporate controls into the operations manual and training so that facility staff are aware of the controls mechanism and response system. 

  • USGBC

    Excerpted from LEED 2009 for Commercial Interiors

    COPYRIGHT © 2009 BY THE U.S. GREEN BUILDING COUNCIL, INC. ALL RIGHTS RESERVED

    IEQ Credit 6.2: Controllability of systems - thermal comfort

    1

    Intent

    To provide a high level of thermal comfort system control1 by individual occupants or groups in multi-occupant spacesConference rooms, classrooms and other indoor spaces used as a place of congregation for presentations, trainings, etc. Individuals using these spaces share the lighting and temperature controls and they should have, at a minimum, a separate zone with accessible thermostat and an air-flow control. Group multi-occupant spaces do not include open office plans that contain individual workstations. (e.g., classrooms or conference areas) and promote their productivity, comfort and well-being.

    Requirements

    Provide individual controls for 50% (minimum) of the tenant occupants to enable adjustment to suit individual needs and preferences, Operable windows may be used in lieu of individual controls for occupants located 20 feet (6 meters) inside and 10 feet (3 meters) to either side of the operable part of the window. The areas of operable window must meet the requirements of ASHRAE Standard 62.1-2007 paragraph 5.1 Natural Ventilation (with errata but without addenda2).

    Conditions for thermal comfort are described in IEQ credit 7.1: Thermal Comfort—Design and include the primary factors of air temperature, radiant temperature, air speed and humidity.

    Provide comfort system controls for all shared multi-occupant spacesConference rooms, classrooms and other indoor spaces used as a place of congregation for presentations, trainings, etc. Individuals using these spaces share the lighting and temperature controls and they should have, at a minimum, a separate zone with accessible thermostat and an air-flow control. Group multi-occupant spaces do not include open office plans that contain individual workstations. to enable adjustments that meet group needs and preferences.

    Potential Technologies & Strategies

    Design the building and systems with comfort controls to allow adjustments to suit individual needs or those of groups in shared spaces. ASHRAE Standard 55-2004 (with errata but without addenda identifies the factors of thermal comfort and a process for developing comfort criteriaComfort criteria are specific design conditions that take into account temperature, humidity, air speed, outdoor temperature, outdoor humidity, seasonal clothing, and expected activity. (ASHRAE 55–2004) for building spaces that suit the needs of the occupants involved in their daily activities. Control strategies can be developed to expand on the comfort criteria and enable individuals to make adjustments to suit individual needs and preferences. These strategies may involve system designs incorporating operable windows, hybrid systems integrating operable windows and mechanical systems, or mechanical systems alone. Individual adjustments may involve individual thermostat controls, local 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. at floor, desk or overhead levels, control of individual radiant panels, or other means integrated into the overall building, thermal comfort systems, and energy systems design. Designers should evaluate the closely tied interactions between thermal comfort as required by ASHRAE Standard 55-2004 (with errata but without addenda)  and acceptable indoor air quality (as required by ASHRAE Standard 62.1-2007 (with errata but without addenda) whether natural or mechanical ventilation.

Organizations

ASHRAE 55-2004

This ASHRAE standard defines the criteria for human comfort that is followed to design mechanical systems.

ASHRAE 62.1 2007

This ASHRAE standard stipulates minimum outdoor air requirement and minimum window opening for naturally ventilated space. This formula is referenced in this credit where windows are used as control mechanism. 

Publications

National Review of Green Schools: Costs, Benefits, and Implications for Massachusetts

This seminal report documents the financial costs and benefits of green schools compared to conventional schools, specifically with reference to Massachusetts. Page six describes the benefits of ventilation controls on occupant productivity.

Operable Windows and HVAC Systems

Taylor Engineering lays out design guidance for integrating operable windows into an HVAC system, while also reducing energy consumption.

Integrated Design and UFAD

In this article from ASHRAE Journal, the authors outline the benefits of an integrated designAn integrated design process (also called "integrative" design by some proponents) relies on a multidisciplinary and collaborative team approach in which members make decisions together based on a shared vision and holistic understanding of the project. Rather than a conventional linear design process in which a design is passed from one professional to another, an integrated process has all key team members talking together through out the design and construction process as they share ideas and use feedback across disciplines to iteratively move toward a high-performing design. approach for underfloor-air distribution, and explain how UFAD can contribute to LEED credits including IEQc6.2. (Subscription Required)

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.

LEED Online Credit Form

Documenting this credit in LEED Online includes completing the table shown here (as samples), with occupancy types and thermal comfort control types indicated.

Operable Windows

Operable windows are an appropriate way to meet the requirements for this credit in many building types. A single operable window can serve multiple occupants, as shown here.

LEED Online Forms: CI-2009 IEQ

The following links take you to the public, informational versions of the dynamic LEED Online forms for each CI-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."

Design Submittal

PencilDocumentation for this credit can be part of a Design Phase submittal.

22 Comments

0
0
Sustentator Argentina Sustentator
Mar 12 2012
LEEDuser Member
195 Thumbs Up

Control on a Store

I'm trying to certify a store under CI, not CI Retail. How would I control the temperature of more than 50% of the space, if the space is my practically my entire shop? Should I provide a manual control (that only my employees can access) to control the temperature? On the other hand, the only workstations that I have are the cashiers, and under IEQ C6.1 I'm providing lightning control for those spaces and not for the rest. I believe this might be inconsistent. Can you help?

1
2
0
Lauren Glasscock Sr. Sustainability Professional, DNV KEMA Energy & Sustainability Mar 12 2012 LEEDuser Expert 8636 Thumbs Up

Hi Romina,

You have to have consistency in your designations between EQc6.1 and EQc6.2 so make sure those match. Can you provide thermal comfort controls for the cashiers? It may not be practical, in which case the point itself may not make sense for your project. The requirement is not that 50% of your space have controls but that 50% of your individual workstations have individual controls and that 100% of your multi-occupant spacesConference rooms, classrooms and other indoor spaces used as a place of congregation for presentations, trainings, etc. Individuals using these spaces share the lighting and temperature controls and they should have, at a minimum, a separate zone with accessible thermostat and an air-flow control. Group multi-occupant spaces do not include open office plans that contain individual workstations. have controllability.

Alternatively, you could reference LEED for Retail in your LEED-CI project application to indicate to the reviewer that you are using the approach for LEED for Retail. I have done this before and have had success with this approach but I cannot guarantee that this would work for your application.

Let me know if this helps a bit...

2
2
0
Sustentator Argentina Sustentator Mar 13 2012 LEEDuser Member 195 Thumbs Up

Thanks Lauren, that helps a lot. I didn't know you can reference to Retail credits, although you are not under that Rating System.

Post a Reply
0
0
Brian Farrelly
Mar 07 2012
LEEDuser Member
174 Thumbs Up

Meeting rooms requirements

An office we are currently working on, is in a long narrow building resulting in 85% of the occupants being close to an operable window, however we have two meeting rooms. One is has a window and the other does not.
To meet this credit would we be require to put some sort of control in both meeting rooms or just the one?

1
2
0
Dylan Connelly Mechanical Engineer, Integral Group Mar 07 2012 LEEDuser Expert 3002 Thumbs Up

Brian,
The credit language reads:
"Provide comfort system controls for all shared multi-occupant spacesConference rooms, classrooms and other indoor spaces used as a place of congregation for presentations, trainings, etc. Individuals using these spaces share the lighting and temperature controls and they should have, at a minimum, a separate zone with accessible thermostat and an air-flow control. Group multi-occupant spaces do not include open office plans that contain individual workstations. to enable adjustments that meet group needs and preferences."
This means you need controls for both meeting rooms. The 50% number only applies to the individual offices and open office spaces.

2
2
0
Lauren Glasscock Sr. Sustainability Professional, DNV KEMA Energy & Sustainability Mar 12 2012 LEEDuser Expert 8636 Thumbs Up

I agree with Dylan. For multi-occupant spacesConference rooms, classrooms and other indoor spaces used as a place of congregation for presentations, trainings, etc. Individuals using these spaces share the lighting and temperature controls and they should have, at a minimum, a separate zone with accessible thermostat and an air-flow control. Group multi-occupant spaces do not include open office plans that contain individual workstations. such as meeting rooms you need some form of thermal comfort control. A window or thermostat would both work.

Post a Reply
0
0
Megan Snyder
May 18 2011
Guest
200 Thumbs Up

EQc6.2 and EAc1.3 for Zoning and Controls

Is it possible to achieve these simultaneously? One appears to require manual control and the other, auto control.

1
4
0
David Posada Sustainability Manager, GBD Architects May 18 2011 LEEDuser Expert 11377 Thumbs Up

It's possible, but not common: EQc 6.2 is difficult to achieve. Usually this would require an underfloor air system (UFAD) with one controllable vent for every two work stations. It may also be possible in a small office where the majority of work spaces are along the perimeter and close to operable windows.

2
4
0
Lauren Glasscock Sr. Sustainability Professional, DNV KEMA Energy & Sustainability Nov 04 2011 LEEDuser Expert 8636 Thumbs Up

It's definitely possible to get both credits as I've done it many times. However, EQc6.2 is tricky as David notes. Remember that EQc6.2 can be achieved with a combination of thermostats (manual controls) as well as operable windows. EQc6.2 can be particularly tricky when you have an open office space area but if you have individual offices with controls it's a little easier. EQc6.2 can also be achieved by controlling any of the thermal comfort criteriaComfort criteria are specific design conditions that take into account temperature, humidity, air speed, outdoor temperature, outdoor humidity, seasonal clothing, and expected activity. (ASHRAE 55–2004) (air temperature, radiant temperature, humidity and air speed).

3
4
0
Cyril Knabe-Nicol Feb 17 2012 Guest 38 Thumbs Up

Dear All,

I am undertaking a project in france and we will reuse the existing system, which will provide heating and cooling from the ceiling and not an underfloor air system (UFAD). For the conference/meeting room and private office we can provide individual adjustable thermostat. But for the Open space office, the system will be link to a BMS. If we are including local control to ensure that 50% of the tenants occupants have an individual controls, will i meet the requirements to achieve this credit.

Thanks

4
4
0
Lauren Glasscock Sr. Sustainability Professional, DNV KEMA Energy & Sustainability Feb 17 2012 LEEDuser Expert 8636 Thumbs Up

Hi Cyril,

What kinds of individual controls are you able to provide in the open office area? If it is the case that 50% of your workstations in your open office area have controls, then it appears you are generally meeting the requirements of the credit.

Remember that for conference rooms and meeting rooms, reviewers will want to see that you have controllability to satisfy the needs of the space. In other words, if you have one area that could be partitioned off from the other, then it might warrant two control settings for these two kinds of spaces. Also, private offices sometimes contain more than one occupant. The reviewer will want to see how many controls you have per person, and not per room when it comes to private offices. So, if you have two people in one private office and one thermostat, then only 50% of those occupants have controllability.

Hope that helps a bit.
Lauren

Post a Reply
0
0
Rick Servoss Mechanical Engineer
May 12 2011
Guest
243 Thumbs Up

Thermal Comfort in Public Spaces

How would one address this credit when the CI project is made up entirely of public space?

1
2
0
Lauren Glasscock Sr. Sustainability Professional, DNV KEMA Energy & Sustainability May 12 2011 LEEDuser Expert 8636 Thumbs Up

Rick,

The credit requires you to provide controls for "building occupants" and doesn't provide details on different requirements for the public vs. employees of the space. The closest guide I've seen that helps to clarify differences that may exist has been in LEED for Retail (http://www.usgbc.org/ShowFile.aspx?DocumentID=7956) whereby EQc6 is revised to state that you need to provide thermal comfort controls for 50% of retail employees in office and administrative spaces (and none for the public).

I'd assume you have some areas with FTEFull-time equivalent (FTE) represents a regular building occupant who spends 8 hours a day (40 hours a week) in the project building. Part-time or overtime occupants have FTE values based on their hours per day divided by 8 (or hours per week divided by 40). Transient Occupants can be reported as either daily totals or as part of the FTE. Residential occupancy should be estimated based on the number and size of units. Core and Shell projects should refer to the default occupancy table in the Reference Guide appendix. All occupant assumptions must be consistent across all credits in all categories. in order to meet the Minimum Program Requirements of LEED. I'd prioritize those areas with controls and then either provide a clear narrative of why the public spaces cannot be reasonably assumed to have controls or find a way to also provide the public with some degree of controls.

I am working on one coffee shop where I am providing controllability for patrons to suit their needs; in this case I am providing reading lamps for visitors to the space.

2
2
0
Rick Servoss Mechanical Engineer Oct 06 2011 Guest 243 Thumbs Up

To update my previous comment, I received a response from the review team stating "the exhibit hall is considered to be a regularly occupied, shared multi-occupant space...." In short, the public space, being the exhibit hall, needs to be included in the template as a shared multi-occupant space. Writing a narrative describing the situation did not suffice.

Post a Reply
0
0
Chi-Chung Sue Steven Leach International Asia Inc. Taiwan Branch
Apr 11 2011
LEEDuser Member
3415 Thumbs Up

Multiple HVAC Zone Controls - Credit towards Individual Comfort?

In a current commerical office project, we are considering the following thermal controls:

-Individual thermostats for each private office or meeting room
-One open office space with +/- 10 workstations, serviced by one operable window and one thermostat with adjustable settings for 3 separate HVAC zones (one for each AC unit serving the space).

The individual thermostats clearly contribute to the credit, but in the open office area where multiple settings are available - does this meet the credit intent for a partial percentage of the occupants? Could it be considered that 3 occupants within this space out of the 10 have "individual controls"?

1
1
0
Lauren Glasscock Sr. Sustainability Professional, DNV KEMA Energy & Sustainability Apr 22 2011 LEEDuser Expert 8636 Thumbs Up

Hi Jason,

Yes, you are all set for the private offices with the individual thermostats.

In terms of the open office area, is it the case where you have 3 occupants that you could argue in each different zone? Are the zones distributed in such a way that one occupant from each zone could realistically go to the thermostat and just change the temperature of their zone and not the others?

If so, I think you can make an argument for achievement through your narrative. I would provide a clear floor plan showing where occupants are in the open floor plan area and how 3 people, in 3 different zones, could control their temperature.

Good luck!

Post a Reply
0
0
Chi-Chung Sue Steven Leach International Asia Inc. Taiwan Branch
Mar 24 2011
LEEDuser Member
3415 Thumbs Up

LEED Online Language

The credit intent and application is very clear as stated above: "Private offices and open space offices need multiple controls for 50% of occupants. One control in each conference or meeting room."

However, on the current version of LEED Online, Table IEQc6.2-1 is a bit confusing in terms of the information being asked for. Each row in the table consists of the following five columns: Space ID, Individual Workspace Type, Thermal Comfort Control Type, Total No. of Spaces, Spaces provided with individual control.

To be in accordance with the credit intent, the last two columns should actually refer to "individual workspaces or workstations" in lieu of "spaces" as in "Space ID." Thus, instead of thermal controls in each space (such as Open Office), we should be inputting controls in individual workstations (such as individual cubicles). Is our assumption and interpretation correct?

1
1
0
Lauren Glasscock Sr. Sustainability Professional, DNV KEMA Energy & Sustainability Mar 29 2011 LEEDuser Expert 8636 Thumbs Up

Hi Jason,

I agree that this Credit Form and its table is confusing! However, no matter what number you put into "Quantity" the ratio always come out 1:1. The reason they did the Template like this was just to try to make things easier for project teams so that if they have, for example, one open office work area with 20 individual occupants they wouldn't have to write down a row for each occupant but could instead group them.

I think your assumptions are correct in that it is really based on your number of controls and not your number of occupants because you could have occupants with no controls which would have to be listed separately with a "quantity" of zero.

Hope that helps a bit.
Lauren

Post a Reply
0
0
Chris Hellstern KMD Architects
Aug 11 2010
Guest
42 Thumbs Up

Controllability of Systems

For a CI 2009 project, our building is able to allow occupants to control thermostats to a range of 70-74 degrees. Would having a specified range such as this be allowable to achieve this credit?

1
3
0
David Posada Sustainability Manager, GBD Architects Aug 12 2010 LEEDuser Expert 11377 Thumbs Up

Are you relying on thermostats as the only user controls or in combination with other controls such as 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. or operable windows? The temperature range might be okay, but thermostats alone may not meet the requirements.

We've only seen this credit achieved in commercial buildings with underfloor air systems that provide control of individual diffusers in the office areas, or small projects with many operable windows. We've understood the credit as having to provide 50% or more of the occupants with individual controls for *each* person. Thus, for 100 people you would need 50 controls, each of which can be individually adjusted.

With a UFAD system, this has been achieved when the number of adjustable floor diffusers in the office areas is equal to or more than 50% of the number of occupants in those areas. With operable windows, we've seen a small, open office along a perimeter with 10 occupants and more than 5 operable windows along the length of the space.

2
3
0
Marian Keeler Senior Associate, Thornton Tomasetti / Simon & Associates Aug 17 2010 LEEDuser Member 2353 Thumbs Up

It is also possible to pursue this credit with a 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 if you provide a large number of VAV boxes and add controllable ceiling grills (such as "thermafusers") so that the number of VAVs plus controllable grills is equal to half the number of occupants. This is not a common approach, but we have tried it with small projects that have a lot of meeting rooms and not many offices.

3
3
0
John Bauer Aug 17 2010 Guest 1155 Thumbs Up

You could do this (thermafuser) also in an open office I would say.

Post a Reply

Start a new LEED comment thread

Welcome !
May 23 2013
Type the characters you see in this picture. (verify using audio)
Type the characters you see in the picture above; if you can't read them, submit the form and a new image will be generated. Not case sensitive.

Copyright 2013 – BuildingGreen, Inc.