Log in
LEED v2009
Commercial Interiors
Indoor Environmental Quality

Thermal Comfort—Design

LEED CREDIT

CI-2009 IEQc7.1: Thermal comfort - design 1 point

See all forum discussions about this credit »

Credit achievement rate

XX%

Upgrade to LEEDuser Premium to see how many projects achieved this credit. Try it free »

LEEDuser expert

Eric Corey Freed

RA, LEED Fellow, Living Future Accredited, EcoDistricts AP

CannonDesign
Senior Vice President, Sustainability

LEEDuser’s viewpoint

Frank advice from LEED experts

LEED is changing all the time, and every project is unique. Even seasoned professionals can miss a critical detail and lose a credit or even a prerequisite at the last minute. Our expert advice guides our LEEDuser Premium members and saves you valuable time.

Credit language

USGBC logo

© Copyright U.S. Green Building Council, Inc. All rights reserved.

Requirements

Design heating, ventilating and air conditioning (HVAC) systems and the building envelope to meet the requirements of one of the options below:

Option 1. ASHRAE standard 55-2004 or non-U.S. equivalent
Meet the requirements of ASHRAE Standard 55-2004, Thermal Comfort Conditions for Human Occupancy (with errata but without addenda1). Demonstrate design compliance in accordance with the Section 6.1.1 documentation. Projects outside the U.S. may use a local equivalent to ASHRAE Standard 55-2004 Thermal Comfort Conditions for Human Occupancy Section 6.1.1. [India ACP: Thermal Comfort]
Option 2. ISO 7730: 2005 & CEN standard EN 15251: 2007
Projects outside the U.S. may earn this credit by designing heating, ventilating and air conditioning (HVAC) systems and the building envelope to meet the requirements of International Organization for Standardization (ISO) 7730: 2005 Ergonomics of the thermal environment, Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria; and CEN Standard EN 15251: 2007, Indoor environmental input parameters for design and assessment of energy performance of buildings addressing indoor air quality, thermal environment, lighting and acoustics.

1 Project teams wishing to use ASHRAE approved addenda for the purposes of this prerequisite may do so at their discretion. Addenda must be applied consistently across all LEED credits.

Alternative Compliance Paths (ACPs)

India ACP: ASHRAE 55-2004 Equivalent
Projects in India may meet the desired comfort criteria specified in the following as a local equivalent to ASHRAE 55-2004:
  • For mechanically conditioned buildings, NBC 2005 Part 8, Section 3 - Table 2
  • For naturally conditioned buildings, NBC 2005 Part 8, Section 1 - Table 9 [view:embed_resource=page_1=10039154][view:embed_resource=page_1=10039154]
See all forum discussions about this credit »

What does it cost?

Cost estimates for this credit

On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.

Our tab contains overall cost guidance, notes on what “soft costs” to expect, and a strategy-by-strategy breakdown of what to consider and what it might cost, in percentage premiums, actual costs, or both.

This information is also available in a full PDF download in The Cost of LEED v4 report.

Learn more about The Cost of LEED v4 »

Frequently asked questions

ASHRAE-55 comfort criteria ask for space air speed. Is this the same as the supply air volume measured in cubic feet per minute (CFM)?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)


What should I do about a warehouse space?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

How can thermal conditions for areas with metabolic rates outside of 1.0–1.3 be determined? (Per ASHRAE Standard 55-2004 Section 5.2.1.1, Figure 5.2.1.1 can be used for areas with metabolic rates between 1.0 and 1.3).

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

There are a few spaces in my project that can’t meet these requirements. Can’t I just exclude them?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

See all forum discussions about this credit »

Addenda

10/1/2012Updated: 2/14/2015
Global ACP
Description of change:
The Requirements section should read as follows: "Design heating, ventilating and air-conditioning (HVAC) systems to meet the requirements of one of the options below."
Campus Applicable
No
Internationally Applicable:
Yes
11/1/2011Updated: 2/14/2015
Reference Guide Correction
Description of change:
In alphabetical order, add the following definition for nonoccupied spaces, "Nonoccupied spaces are defined as spaces designed for equipment and machinery or storage with no human occupancy except for maintenance, repairs, and equipment retrieval."
Campus Applicable
No
Internationally Applicable:
No
10/1/2012Updated: 2/14/2015
Global ACP
Description of change:
Add a new option that reads: "OPTION 1. ASHRAE Standard 55-2004 or Non-U.S. Equivalent Meet the requirements of ASHRAE Standard 55-2004, Thermal Comfort Conditions for Human Occupancy (with errata but without addenda). Demonstrate design compliance in accordance with the Section 6.1.1 documentation. Projects outside the U.S. may use a local equivalent to ASHRAE Standard 55-2004 Thermal Comfort Conditions for Human Occupancy Section 6.1.1."
Campus Applicable
No
Internationally Applicable:
Yes
10/1/2012Updated: 2/14/2015
Global ACP
Description of change:
Add a new option that reads: "OPTION 2. ISO 7730: 2005 & CEN Standard EN 15251: 2007 Projects outside the U.S. may earn this credit by designing heating, ventilating and air conditioning (HVAC) systems and the building envelope to meet the requirements of International Organization for Standardization (ISO) 7730: 2005 Ergonomics of the thermal environment, Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria; and CEN Standard EN 15251: 2007, Indoor environmental input parameters for design and assessment of energy performance of buildings addressing indoor air quality, thermal environment, lighting and acoustics."
Campus Applicable
No
Internationally Applicable:
Yes
11/1/2011Updated: 2/14/2015
Reference Guide Correction
Description of change:
In alphabetical order, add the following definition for nonoccupied spaces, "Nonoccupied spaces are defined as spaces designed for equipment and machinery or storage with no human occupancy except for maintenance, repairs, and equipment retrieval."
Campus Applicable
No
Internationally Applicable:
No
4/1/2013
LEED Interpretation
Inquiry:

Can spaces that fall outside of the scope of ASHRAE 55-2004, because the physical activity levels result in a time-averaged MET above 2.0 (such as gymnasiums or fitness centers), be excluded from the credit requirements? Also, can spaces that are not normally comfort conditioned (such as warehouse spaces, apparatus bays, vehicle repair facilities, commercial kitchens) be excluded from the credit requirements?

Ruling:

**Updated October 1, 2013 to clarify the ruling.
No, spaces with a time-averaged metabolic rate above 2.0 MET must meet the requirements for IEQc7.1 Thermal Comfort—Design/IEQc2.3 Occupant Comfort—Thermal Comfort Monitoring. For these unique spaces, an alternative to the requirements of ASHRAE 55-2004 is acceptable provided the project determines acceptable thermal comfort conditions that meet the intent of the credit, and demonstrates that those conditions will be met. Time-weighted average metabolic rates should be determined based on guidance in ASHRAE 55-2004, Normative Appendix A. Most spaces with MET levels above 2.0 would need to meet the cooling / humidity temperature set points for spaces with MET levels of 2.0 in order to meet the intent of the credit. Exceptions will be considered on a case-by-case basis and must include an explanation that justifies how the intent of the credit is met. Kitchens may pursue this option.

Spaces that are not normally comfort conditioned can only be excluded if they are non-regularly occupied. For regularly occupied spaces that are not normally comfort conditioned, and not able to meet the ASHRAE 55 thermal comfort conditions, the project team must include one or more of the following design alternatives: radiant flooring; circulating fans; passive systems, such as nighttime air, heat venting, or wind flow; localized active cooling (refrigerant or evaporative-based systems) or heating systems; or localized, hard-wired fans that provide air movement for occupants’ comfort.

Campus Applicable
No
Internationally Applicable:
Yes
See all forum discussions about this credit »

Checklists

Step by step to LEED certification

LEEDuser’s checklists walk you through the key action steps you need to earn a credit, including how to avoid common pitfalls and save money.

See all forum discussions about this credit »

Documentation toolkit

The motherlode of cheat sheets

LEEDuser’s Documentation Toolkit is loaded with calculators to help assess credit compliance, tracking spreadsheets for materials, sample templates to help guide your narratives and LEED Online submissions, and examples of actual submissions from certified LEED projects for you to check your work against. To get your plaque, start with the right toolkit.

Credit achievement rate

XX%

Upgrade to LEEDuser Premium to see how many projects achieved this credit. Try it free »

LEEDuser expert

Eric Corey Freed

RA, LEED Fellow, Living Future Accredited, EcoDistricts AP

CannonDesign
Senior Vice President, Sustainability

Get the inside scoop

Our editors have written a detailed analysis of nearly every LEED credit, and LEEDuser premium members get full access. We’ll tell you whether the credit is easy to accomplish or better left alone, and we provide insider tips on how to document it successfully.

USGBC logo

© Copyright U.S. Green Building Council, Inc. All rights reserved.

Requirements

Design heating, ventilating and air conditioning (HVAC) systems and the building envelope to meet the requirements of one of the options below:

Option 1. ASHRAE standard 55-2004 or non-U.S. equivalent
Meet the requirements of ASHRAE Standard 55-2004, Thermal Comfort Conditions for Human Occupancy (with errata but without addenda1). Demonstrate design compliance in accordance with the Section 6.1.1 documentation. Projects outside the U.S. may use a local equivalent to ASHRAE Standard 55-2004 Thermal Comfort Conditions for Human Occupancy Section 6.1.1. [India ACP: Thermal Comfort]
Option 2. ISO 7730: 2005 & CEN standard EN 15251: 2007
Projects outside the U.S. may earn this credit by designing heating, ventilating and air conditioning (HVAC) systems and the building envelope to meet the requirements of International Organization for Standardization (ISO) 7730: 2005 Ergonomics of the thermal environment, Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria; and CEN Standard EN 15251: 2007, Indoor environmental input parameters for design and assessment of energy performance of buildings addressing indoor air quality, thermal environment, lighting and acoustics.

1 Project teams wishing to use ASHRAE approved addenda for the purposes of this prerequisite may do so at their discretion. Addenda must be applied consistently across all LEED credits.

Alternative Compliance Paths (ACPs)

India ACP: ASHRAE 55-2004 Equivalent
Projects in India may meet the desired comfort criteria specified in the following as a local equivalent to ASHRAE 55-2004:
  • For mechanically conditioned buildings, NBC 2005 Part 8, Section 3 - Table 2
  • For naturally conditioned buildings, NBC 2005 Part 8, Section 1 - Table 9 [view:embed_resource=page_1=10039154][view:embed_resource=page_1=10039154]

XX%

Upgrade to LEEDuser Premium to see how many projects achieved this credit. Try it free »

Got the gist of IEQc7.1 but not sure how to actually achieve it? LEEDuser gives step-by-step help. Premium members get:

  • Checklists covering all the key action steps you'll need to earn the credit.
  • Hot tips to give you shortcuts and avoid pitfalls.
  • Cost tips to assess what a credit will actually cost, and how to make it affordable.
  • Ideas for going beyond LEED with best practices.
  • All checklists organized by project phase.
  • On-the-fly suggestions of useful items from the Documentation Toolkit and Credit Language.

In the end, LEED is all about documentation. LEEDuser’s Documentation Toolkit, for premium members only, saves you time and helps you avoid mistakes with:

  • Calculators to help assess credit compliance.
  • Tracking spreadsheets for materials purchases.
  • Spreadsheets and forms to give to subs and other team members.
  • Guidance documents on arcane LEED issues.
  • Sample templates to help guide your narratives and LEED Online submissions.
  • Examples of actual submissions from certified LEED projects.

ASHRAE-55 comfort criteria ask for space air speed. Is this the same as the supply air volume measured in cubic feet per minute (CFM)?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)


What should I do about a warehouse space?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

How can thermal conditions for areas with metabolic rates outside of 1.0–1.3 be determined? (Per ASHRAE Standard 55-2004 Section 5.2.1.1, Figure 5.2.1.1 can be used for areas with metabolic rates between 1.0 and 1.3).

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

There are a few spaces in my project that can’t meet these requirements. Can’t I just exclude them?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

10/1/2012Updated: 2/14/2015
Global ACP
Description of change:
The Requirements section should read as follows: "Design heating, ventilating and air-conditioning (HVAC) systems to meet the requirements of one of the options below."
Campus Applicable
No
Internationally Applicable:
Yes
11/1/2011Updated: 2/14/2015
Reference Guide Correction
Description of change:
In alphabetical order, add the following definition for nonoccupied spaces, "Nonoccupied spaces are defined as spaces designed for equipment and machinery or storage with no human occupancy except for maintenance, repairs, and equipment retrieval."
Campus Applicable
No
Internationally Applicable:
No
10/1/2012Updated: 2/14/2015
Global ACP
Description of change:
Add a new option that reads: "OPTION 1. ASHRAE Standard 55-2004 or Non-U.S. Equivalent Meet the requirements of ASHRAE Standard 55-2004, Thermal Comfort Conditions for Human Occupancy (with errata but without addenda). Demonstrate design compliance in accordance with the Section 6.1.1 documentation. Projects outside the U.S. may use a local equivalent to ASHRAE Standard 55-2004 Thermal Comfort Conditions for Human Occupancy Section 6.1.1."
Campus Applicable
No
Internationally Applicable:
Yes
10/1/2012Updated: 2/14/2015
Global ACP
Description of change:
Add a new option that reads: "OPTION 2. ISO 7730: 2005 & CEN Standard EN 15251: 2007 Projects outside the U.S. may earn this credit by designing heating, ventilating and air conditioning (HVAC) systems and the building envelope to meet the requirements of International Organization for Standardization (ISO) 7730: 2005 Ergonomics of the thermal environment, Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria; and CEN Standard EN 15251: 2007, Indoor environmental input parameters for design and assessment of energy performance of buildings addressing indoor air quality, thermal environment, lighting and acoustics."
Campus Applicable
No
Internationally Applicable:
Yes
11/1/2011Updated: 2/14/2015
Reference Guide Correction
Description of change:
In alphabetical order, add the following definition for nonoccupied spaces, "Nonoccupied spaces are defined as spaces designed for equipment and machinery or storage with no human occupancy except for maintenance, repairs, and equipment retrieval."
Campus Applicable
No
Internationally Applicable:
No
4/1/2013
LEED Interpretation
Inquiry:

Can spaces that fall outside of the scope of ASHRAE 55-2004, because the physical activity levels result in a time-averaged MET above 2.0 (such as gymnasiums or fitness centers), be excluded from the credit requirements? Also, can spaces that are not normally comfort conditioned (such as warehouse spaces, apparatus bays, vehicle repair facilities, commercial kitchens) be excluded from the credit requirements?

Ruling:

**Updated October 1, 2013 to clarify the ruling.
No, spaces with a time-averaged metabolic rate above 2.0 MET must meet the requirements for IEQc7.1 Thermal Comfort—Design/IEQc2.3 Occupant Comfort—Thermal Comfort Monitoring. For these unique spaces, an alternative to the requirements of ASHRAE 55-2004 is acceptable provided the project determines acceptable thermal comfort conditions that meet the intent of the credit, and demonstrates that those conditions will be met. Time-weighted average metabolic rates should be determined based on guidance in ASHRAE 55-2004, Normative Appendix A. Most spaces with MET levels above 2.0 would need to meet the cooling / humidity temperature set points for spaces with MET levels of 2.0 in order to meet the intent of the credit. Exceptions will be considered on a case-by-case basis and must include an explanation that justifies how the intent of the credit is met. Kitchens may pursue this option.

Spaces that are not normally comfort conditioned can only be excluded if they are non-regularly occupied. For regularly occupied spaces that are not normally comfort conditioned, and not able to meet the ASHRAE 55 thermal comfort conditions, the project team must include one or more of the following design alternatives: radiant flooring; circulating fans; passive systems, such as nighttime air, heat venting, or wind flow; localized active cooling (refrigerant or evaporative-based systems) or heating systems; or localized, hard-wired fans that provide air movement for occupants’ comfort.

Campus Applicable
No
Internationally Applicable:
Yes

LEEDuser expert

Eric Corey Freed

RA, LEED Fellow, Living Future Accredited, EcoDistricts AP

CannonDesign
Senior Vice President, Sustainability

See all LEEDuser forum discussions about this credit » Unsubscribe from discussions about CI-2009 IEQc7.1