Log in
LEED v4.1
New Construction
Energy and Atmosphere
Minimum Energy Performance

LEED CREDIT

NC-v4.1 EAp2: Minimum Energy Performance Required

See all forum discussions about this credit »
View the LEED v4 version of this credit »

SPECIAL REPORT

LEEDuser expert

Marcus Sheffer

7group / Energy Opportunities
LEED Fellow

SPECIAL REPORT

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.

Intent

To promote resilience and reduce the environmental and economic harms of excessive energy use and greenhouse gas emissions that disproportionately impact frontline communities by achieving a minimum level of energy efficiency for the building and its systems.

Requirements

Comply with ANSI/ASHRAE/IESNA Standard 90.1–2016, with errata or a USGBC-approved equivalent standard.

ASHRAE 90.1-2016 Compliance pathways in Section 4.2.1.1 include compliance with all mandatory provisions, and compliance with one of the following:

  • Prescriptive provisions of Sections 5 through 10
  • Section 11 Energy Cost Budget Method
  • Normative Appendix G Performance Rating Method. When using Appendix G, the Performance Cost Index (PCI) shall be less than or equal to the Performance Cost Index Target (PCIt) in accordance with the methodology provided in Section 4.2.1.1. Document the PCI, PCIt, and percentage improvement using metrics of cost or greenhouse gas (GHG) emissions.
  • Exception to Mandatory Measures requirements: For ASHRAE 90.1-2016 mandatory provisions where the Appendix G Performance Rating Method provides a methodology for demonstrating savings between the Proposed Building Performance (PBP) and the Baseline Building Performance (BBP), projects may model the Proposed Building Performance as designed in lieu of compliance with the mandatory provisions.
  • Exceptional Calculations modeled in accordance with Section G2.5 may be modeled to document minimum prerequisite compliance.
  • Only on-site or on-campus renewable energy that meets ASHRAE Standard 90.1-2016 Section G 2.4.1 requirements for on-site renewable energy may be used to meet ASHRAE Standard 90.1-2016 performance requirements.
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 »

Addenda

4/21/2023Updated: 5/9/2023
Rating System Correction
Description of change:
Revise the Intent to read as: "...excessive energy use and greenhouse gas emissions that disproportionately..."

Under Requirement delete "For projects using Normative Appendix G Performance Rating Method"

Revise the bullet that starts with "Exception to Mandatory measures requirements:" to read as: " Exception to Mandatory Measures requirements: For ASHRAE 90.1-2016 mandatory provisions where the Appendix G Performance Rating Method provides a methodology for demonstrating savings between the Proposed Building Performance (PBP) and the Baseline Building Performance (BBP), projects may model the Proposed Building Performance as designed in lieu of compliance with the mandatory provisions.

Remove the word "minimum" from the last bullet of Requirements
Campus Applicable
No
Internationally Applicable:
No
4/21/2023Updated: 5/9/2023
Reference Guide Correction
Description of change:
Please refer to the April 2023 tracked changes to view all Reference Guide updates for this credit.
Campus Applicable
No
Internationally Applicable:
No
4/9/2021Updated: 4/20/2021
Reference Guide Correction
Description of change:
RATING SYSTEM:
1. For projects using Normative Appendix G Performance Rating Method, under the subheading "International", revise the first bullet point to read as follows:

International:
o use the latest national grid mix coefficients from the International Energy Agency to calculate GHG emissions by energy source

REFERENCE GUIDE:

2. Further Explanation > Greenhouse Gas Emissions section

In the Greenhouse Gas Emissions section, revise the first sentence in the 4th paragraph to read as follows:
"International projects may use the latest national coefficients from the International Energy Agency to calculate GHG emissions by energy source, or determine greenhouse gas emissions factors for each building energy source based on ISO 52000-1:2017 Energy Performance of Buildings."


3. Further Explanation > International Tips section

In the International Tips section, under Option 1. Tenant-Level Energy Performance Compliance, below the paragraph that begins "Canada: Use the Provincial emissions factors..." add the following paragraph:

"Europe: The Europe ACP for ASHRAE 90.1 Mandatory Provisions Table provides further guidance for project teams in Europe wishing to use European standards in lieu of certain ASHRAE 90.1-2016 mandatory provisions in LEED v4.1. The guidance covers ASHRAE 90.1-2016 Mandatory Provision Sections 5.4, 6.4, 7.4, 8.4, 9.4 and 10. Column 1 of the table references the specific subsection used in ASHRAE 90.1-2016. Column 2 displays the requirement as written in ASHRAE 90.1-2016. Column 3 outlines the compliance pathway available for European projects. Column 4 includes, in some cases, further information about the proposal, differences between the proposal and the ASHRAE requirement, or a reference to further documentation.

Additionally, for projects using the Performance Option for compliance with EA prerequisite Minimum Energy Performance and EA credit Optimize Energy Performance, the documentation must also use the calculated U-factor for fenestration products including windows and skylights based on either the LBNL Windows 6 program, or a simulation software program that approximates the NFRC rating methodologies. Alternatively, a narrative shall be provided supporting the claim that the fenestration U-factor used in the model is similar to the values that would be achieved using the NFRC rating. The CE-marked fenestration does not account for thermal bridging and seasonal performance in the same way as the NFRC rating, and when accounted for in the energy model, has been observed to lead to savings that exceed those claimed for the same fenestration rated under the NFRC ratings."

Campus Applicable
No
Internationally Applicable:
No
4/9/2021Updated: 4/20/2021
Rating System Correction
Description of change:
RATING SYSTEM:
1. For projects using Normative Appendix G Performance Rating Method, under the subheading "International", revise the first bullet point to read as follows:

International:
o use the latest national grid mix coefficients from the International Energy Agency to calculate GHG emissions by energy source

REFERENCE GUIDE:

2. Further Explanation > Greenhouse Gas Emissions section

In the Greenhouse Gas Emissions section, revise the first sentence in the 4th paragraph to read as follows:
"International projects may use the latest national coefficients from the International Energy Agency to calculate GHG emissions by energy source, or determine greenhouse gas emissions factors for each building energy source based on ISO 52000-1:2017 Energy Performance of Buildings."


3. Further Explanation > International Tips section

In the International Tips section, under Option 1. Tenant-Level Energy Performance Compliance, below the paragraph that begins "Canada: Use the Provincial emissions factors..." add the following paragraph:

"Europe: The Europe ACP for ASHRAE 90.1 Mandatory Provisions Table provides further guidance for project teams in Europe wishing to use European standards in lieu of certain ASHRAE 90.1-2016 mandatory provisions in LEED v4.1. The guidance covers ASHRAE 90.1-2016 Mandatory Provision Sections 5.4, 6.4, 7.4, 8.4, 9.4 and 10. Column 1 of the table references the specific subsection used in ASHRAE 90.1-2016. Column 2 displays the requirement as written in ASHRAE 90.1-2016. Column 3 outlines the compliance pathway available for European projects. Column 4 includes, in some cases, further information about the proposal, differences between the proposal and the ASHRAE requirement, or a reference to further documentation.

Additionally, for projects using the Performance Option for compliance with EA prerequisite Minimum Energy Performance and EA credit Optimize Energy Performance, the documentation must also use the calculated U-factor for fenestration products including windows and skylights based on either the LBNL Windows 6 program, or a simulation software program that approximates the NFRC rating methodologies. Alternatively, a narrative shall be provided supporting the claim that the fenestration U-factor used in the model is similar to the values that would be achieved using the NFRC rating. The CE-marked fenestration does not account for thermal bridging and seasonal performance in the same way as the NFRC rating, and when accounted for in the energy model, has been observed to lead to savings that exceed those claimed for the same fenestration rated under the NFRC ratings."

Campus Applicable
No
Internationally Applicable:
No
4/9/2021Updated: 4/19/2021
Rating System Correction
Description of change:
EA prerequisite Minimum Energy Performance:
- revise Intent to read as follows: "To promote resilience and reduce the environmental and economic harms of excessive energy use that disproportionately impact frontline communities by achieving a minimum level of energy efficiency for the building and its systems."

EA credit Optimize Energy Performance:
- revise Intent to read as follows: "To achieve increasing levels of energy performance beyond the prerequisite standard to reduce environmental and economic harms associated with excessive energy use that disproportionately impact frontline communities."
Campus Applicable
No
Internationally Applicable:
No
7/25/2019Updated: 3/1/2021
Reference Guide Correction
Description of change:
Before the section "Referenced Standards" add a new section that reads as follows:

"International Tips

Option 1. Energy Performance Compliance

Canada:
Use the Provincial (where available) emissions factors reported in the National Inventory Report, submitted by Canada to the United Nations Framework Convention on Climate Change, to calculate GHG emissions by energy source; these emissions factors are readily found in the ENERGY STAR Portfolio Manager Greenhouse Gas Emissions Technical Reference (https://portfoliomanager.energystar.gov/pdf/reference/Emissions.pdf)."
Campus Applicable
No
Internationally Applicable:
No
11/9/2020Updated: 12/7/2020
Regional ACP
Description of change:
See the Resource Library for full ACP requirements and documentation.
Campus Applicable
No
Internationally Applicable:
No
11/10/2020Updated: 11/25/2020
Reference Guide Correction
Description of change:
Step-by-Step Guidance:

1. Under Step 2. Review and address ASHRAE mandatory requirements, add the below text as a new bullet point below the bullet point "Confirm that compliant components are included in the final construction documents.":
"Projects are encouraged to design the project to comply with the mandatory energy monitoring provisions defined in Section 6.4.3.11.1 Monitoring and Section 8.4.3 electrical energy monitoring. However, since these requirements are separately addressed in EA Prerequisite Building-Level Energy Metering and EA Credit Advanced Energy Metering, projects are not required to comply with the mandatory provisions from these two sections."

2. In the first sentence under Step 3. Identify energy use target for building, replace both instances of "EA credit Optimize Energy Performance" with "IP credit Integrative Process"

3. Under Step 4. Select option for credit compliance, in the first sentence in the last bullet point in the list, remove the word "also" so that the sentence reads as follows: " If the project is not pursuing any points under EA credit Optimize Energy Performance, the project may demonstrate EA prerequisite Minimum Energy Performance compliance using ASHRAE 90.1-2016 Section 11 Energy Cost Budget. "

4. Under Step 5. Develop preliminary energy model or alternate energy analysis, revise the second half of the first sentence "To achieve EA credit Optimize Energy Performance, project teams must analyze efficiency measures during the design process," so that it reads as follows:
"focusing on load reduction and HVAC-related strategies or passive measures appropriate for the facility, and account for the results during design decision making."

5. Under Step 6. below the sentence that reads "Once the HVAC system and other design parameters are established, build or update the proposed building energy model to reflect the anticipated design", before the final 2 bullet points that start "Energy costs and greenhouse gas emissions offset by on-site or on-campus renewable energy systems..." and "Energy costs and greenhouse gas emissions offset..." adda new section header titled "Renewable Energy in the Energy Model." Beneath the new section header add the following 2 bullet points:
" Energy costs and greenhouse gas emissions offset by on-site or on-campus renewable energy systems count towards energy savings for compliance with the prerequisite when these systems are included on the building permit or on a master site permit including the building for a contiguous campus consistent with ASHRAE Standard 90.1-2016 Section G2.4.1 requirements, and associated environmental attributes are retained by the building owner. ASHRAE 90.1-2016 defines on-site renewable energy as “energy generated from renewable sources produced at the building site”, which includes on-site photovoltaics systems, wind generators, or thermal or electric generation from methane capture or qualifying biofuel sourced from the project or campus site, but does not include electric generation or thermal generation from off-site renewable sources.
 Greenhouse gas emissions offset by New Tier 2 off-site renewable energy systems qualifying under EA credit Renewable Energy may be included in the model for achievement of points using the greenhouse gas emissions calculation under EA credit Optimize Energy Performance, but may not be included in the model for prerequisite compliance. Modeled building GHG emissions and avoided GHG emissions from Tier 2 off-site renewable energy can be modeled using the hourly generation profile from the project’s grid region and the renewable generation grid region in locations where hourly emissions factors are available."

6. Revise the final two sentences at the bottom of Step 6 so that they read as follows: "Use the results from the baseline and proposed models and the Building Performance Factor to determine the anticipated energy cost and greenhouse gas emissions savings (see Further Explanation, Energy Savings). Either the cost or the GHG emissions metric may be used to show prerequisite compliance."

Further Explanation:

7. Climate Zone Determination: add the following sentence to the end of the second paragraph, after the sentence "For locations outside of the U.S. and Canada, refer to the closest or most similar location in Table Annex 1-3.":
"International projects may also refer to ASHRAE Standard 169-2013 to determine the project’s climate zone based on historical weather data for the project’s location."

8. Performance Path: In the final paragraph in the "Performance Path" section:
- In the first sentence of the paragraph, add "and all mandatory measures from each Section" after the "Appendix G" so that the parentheses appear as follows: "(Appendix G and all mandatory measures from each Section in particular)"
- Revise the last sentence in the paragraph so that it reads as follows: "The energy modeler should also consider reading the ASHRAE 90.1–2016 User’s Manual, which provides examples and further guidance relevant to Appendix G."

9. Prescriptive Paths: In the sentence that begins "Although the prescriptive paths are applicable to some large or complex projects," strike the words "schools and".

10. Schedules: Delete the sentence "Refer to the LEED v4 reference guide". Add the following text:
"If anticipated operating schedules are unknown, helpful guidance for determining model inputs for occupancy, lighting, HVAC system, receptacle power, and service hot water consumption values can be found in the ASHRAE 90.1–2016 User’s Manual, Appendix G.

Align the time steps used in the modeled schedules with the time steps used for determining peak demand. For elevators, the modeled peak power for the elevator motors must either be scaled down from the instantaneous peak by an equal factor in the baseline and proposed design to represent the hourly peak, or the fractional schedule modeled for elevators shall have a peak operating percentage that aligns with the peak hourly demand as a fraction of the peak instantaneous demand. For example, if the peak elevator motor power for the proposed design is 100 kW, the peak elevator motor power for the baseline design is 120 kW, and the peak hourly demand for the proposed elevators is 5 kW, the elevator motor power shall either be modeled as: hourly schedules that peak at 100% of design power, and peak hourly demand modeled as 5 kW in the Proposed Design and 6 kW in the Baseline design; or hourly schedules that peak at 5% (including for Baseline HVAC system sizing), and peak hourly demand modeled as 100 kW in the Proposed Design and 120 kW in the Baseline design.

Similar schedule or peak hourly load adjustments apply for receptacle power (with maximum connected load versus peak hourly demand) and service water heating (with maximum instantaneous flow versus peak hourly demand).

Schedules must be identical in both the baseline and the proposed cases unless documented in an exceptional calculation or specifically allowed by ASHRAE 90.1–2016 Appendix G (see Further Explanation, Exceptional Calculation Method).

Certain space types may require specific schedules based on anticipated operation and may vary by space type. For example, a server room may have different temperature schedules than an occupied space. Exceptions to Section G3.1.1 may require modeling of a different baseline HVAC system type in spaces with schedules that vary significantly from the rest of the building.

Different lighting schedules should be used for a project with both office and retail occupancy when the space-by-space method is used, or when the building area method is used with multiple building type classifications. Different schedules cannot be used, however, if an average lighting power density is applied to the whole project."

11. Energy Cost: In the sentence that begins "Per ASHRAE 90.1-2016, to qualify as an on-site system, the renewable energy must be generated on-site from renewable sources produced at the building..." in the second paragraph, strike the "and" after "at the building", and add the following text after the phrase "the system must be part of the project scope of work": ", and the renewable attributes must be retained for the project building."

12. Greenhouse Gas Emissions:
- Delete the sentence "For projects that are using biofuels to generate electricity or heat within the building, contact USGBC to discuss the appropriate method for deriving Greenhouse Gas Emission factors. "
- in the final sentence that begins "For Optimize Energy Performance credit compliance..." replace the phrase "new off-site" with "Tier 2 off-site"
- after the sentence that begins "For Optimize Energy Performance credit compliance..." add the following sentence: "For projects claiming credit for GHG emissions reductions associated with Tier 2 off-site renewable energy in EA credit Optimize Energy Performance, building GHG emissions and avoided GHG emissions from Tier 2 off-site renewable energy can be modeled using the hourly generation profile from the project’s grid region and the renewable generation grid region in locations where hourly emissions factors are available."

13. In Table 3. Changes in ASHRAE 90.1 Performance Rating Method Requirements, 2010 to 2016, under HVAC & Refrigeration Equipment, in the row "HVAC System Type (G3.1.1, Table G3.1#10, Table G3.1.1-3, Table G3.1.1-4)", revise the text in the column "ASHRAE 90.1-2016 Appendix G": move the sentence that begins "Baseline system heating type is dependent on climate zone rather..." and the sentence that begins "Baseline fossil fuel heating systems shall always be modeled using natural gas..." so that they appear before the sentences that begin "Further clarity is provided for identifying the order of priority..." and "Additional HVAC system type categorizations added..."

Rating System Variations

14. Retail: Add the phrase "except for refrigeration equipment and kitchen hood requirements specifically addressed by ASHRAE 90.1-2016." to the end of the bullet point that reads " Refer to Appendix 3. Table 1 for energy consumption values of equipment and refrigeration"

Project Type Variations

15. Option 1. Canada: add "Provincial" before "emissions factors" and "(where available)" after "emissions factors" to the sentence so that it reads: "Use the Provincial emissions factors (where available) reported in the National Inventory Report, submitted by Canada to the United Nations Framework Convention on Climate Change..."
Campus Applicable
No
Internationally Applicable:
No
11/10/2020Updated: 11/25/2020
Rating System Correction
Description of change:
Under the heading "For projects using Normative Appendix G Performance Rating Method:" make the following changes:

1. delete "and Canada" from the sub-heading that reads "US and Canada"
2. beneath the bullet point "use hourly emissions profiles from U.S. Environmental Protection Agency’s (EPA) AVoided Emissions and geneRation Tool (AVERT)", and a new sub-heading that reads "Canada:". Underneath "Canada:" add the following bullet point:

"o use the provincial (where available) emissions factors reported in the National Inventory Report, submitted by Canada to the United Nations Framework Convention on Climate Change, to calculate GHG emissions by energy source; these emissions factors are readily found in the ENERGY STAR Portfolio Manager Greenhouse Gas Emissions Technical Reference."
Campus Applicable
No
Internationally Applicable:
No
4/10/2020Updated: 4/17/2020
Form Update
Description of change:
Changes made:
• Improved general functionality and formatting
• Bug fixes for the General Info, Schedules, Multifamily Details, Shading and Fenestration, Lighting Counts, Process Loads, General HVAC, Baseline Air-side HVAC, Proposed Air-side HVAC, and Water-Side HVAC tabs
• Updates to Performance Output tabs to reflect v4.1 rating system updates
Campus Applicable
No
Internationally Applicable:
No
11/14/2019Updated: 11/14/2019
Form Update
Description of change:
LEED v4.1 Minimum Energy Performance Calculator published
Campus Applicable
No
Internationally Applicable:
Yes
7/25/2019Updated: 7/30/2019
Reference Guide Correction
Description of change:
Add the following reference to the list of Referenced Standards, including the direct link to the resource:

Developing Performance Cost Index Targets for ASHRAE Standard 90.1 Appendix G - Performance Rating Method
https://www.pnnl.gov/main/publications/external/technical_reports/PNNL-2...
Campus Applicable
No
Internationally Applicable:
No
4/9/2019
LEED Interpretation
Inquiry:

Our project is subject to ASHRAE Standard 90.1-2013 for code compliance. To pursue Option 1: Energy Performance Compliance in LEED v4.1 BD+C, is there a methodology for documenting additional energy performance for LEED v4.1 projects regulated by ASHRAE Standard 90.1-2013?

Ruling:

Yes, projects applying Option 1: Energy Performance Compliance, and regulated by ASHRAE Standard 90.1-2013 or IECC 2015 may document achievement of LEED v4.1 BD+C EA Prerequisite Minimum Energy Performance and EA Credit Optimize Energy Performance as described below:
Comply with all mandatory provisions of ASHRAE Standard 90.1-2013 or IECC 2015.

AND

Demonstrate a Percentage improvement in the Proposed Building Performance beyond the Baseline Building performance in accordance with ANSI/ASHRAE/IESNA Standard 90.1-2013, Appendix G.

Calculate the Baseline Building Performance, Proposed Building Performance, and Percentage Improvement using metrics of cost and greenhouse gas (GHG) emissions. For each energy source serving the building, the GHG emission factors must be identical for the Baseline and Proposed building models.

The LEED prerequisite Percentage Improvement requirements may be demonstrated either using metrics of cost from Table 1 or greenhouse gas (GHG) emissions from Table 2. LEED points are calculated based on the project percent improvement for cost and GHG emissions. Total points have been divided equally between the metrics of energy cost and greenhouse gas emissions. Points are awarded according to Table 1 and Table 2.

For project percent improvement for the cost metric, on-site renewable energy may be subtracted from proposed energy cost prior to calculating proposed building performance per ASHRAE Standard 90.1-2013 Section G 2.4.1.

Table 1. Points for percentage improvement in energy performance – Cost (1-9 points NC and CS, 1-8 points Schools, 1-10 points Healthcare)

New
Construction
(except
Healthcare,
Schools,
Multifamily
Residential)
Healthcare,
Major
Renovation,
CS

Schools
Points
BD+C
(except
Schools,
Healthcare)
Points
Healthcare
Points
Schools

7%
3%
15%
Prerequisite
Prerequisite
Prerequisite

12%
5%
20%
1
1
1

17%
8%
25%
2
2
2

22%
13%
30%
3
3
3

27%
18%
35%
4
4
4

32%
23%
40%
5
5
5

37%
28%
45%
6
6
6

42%
33%
50%
7
7
7

47%
38%
-
8
8
-

52%
43%
60%
9
9
8

57%
48%
65%
EP
10
EP

-
53%
-
-
EP
-

On-site renewable energy may be subtracted from proposed greenhouse gas emissions prior to calculating proposed building performance per ASHRAE Standard 90.1-2013 Section G 2.4.1. New off-site renewable energy as defined in EA credit Renewable Energy may be subtracted from proposed greenhouse gas emissions prior to calculating proposed building performance.

Table 2. Points for percentage improvement in energy performance – Greenhouse Gas Emissions (1-9 points NC, 1-8 points Schools, 1-10 points Healthcare)

New Construction (except Healthcare, Schools, Multifamily Residential)
Healthcare, Major Renovation, CS
Schools
Points BD+C (except Schools, Healthcare)
Points Healthcare
Points Schools

7%
3%
15%
Prerequisite
Prerequisite
Prerequisite

12%
5%
20%
1
1
1

17%
8%
25%
2
2
2

23%
13%
31%
3
3
3

31%
19%
37%
4
4
4

39%
27%
43%
5
5
5

47%
35%
50%
6
6
6

55%
43%
60%
7
7
7

65%
50%
-
8
8
-

80%
65%
80%
9
9
8

100%
80%
100%
EP
10
EP

-
100%
-
-
EP
-

Campus Applicable
No
Internationally Applicable:
No
1/4/2016
LEED Interpretation
Inquiry:

Where the local code does not require vestibules or allows alternatives, can the project team take a penalty for not including vestibules in the design model?

Ruling:

Yes, in locations where the local code does not require vestibules or revolving doors the project team may choose one of the two options below. Additionally, all projects using this method must provide a narrative explaining how infiltration and exfiltration of air through building entries is addressed in the design.

1. Manual subtraction of the energy cost savings associated with vestibules as conservatively estimated by PNNL-20026 “Energy Saving Impact of ASHRAE 90.1 Vestibule Requirements: Modeling of Air Infiltration through Door Openings”. Refer to the Related Resource “Default Deduction for Vestibules” for the specific percentage subtraction required based on project type and climate zone.
2. Provide detailed exceptional calculation method calculations with each step of the calculation clearly described and in alignment with the analysis performed in PNNL-20026, but specific to the project building. Document the additional energy consumption of the project building associated with removing the vestibules from the project. No credit will be given for the use of air curtains when using this approach. A sensitivity analysis related to the number of occupants entering on an hourly basis would need to be justified. The narrative would also need to justify that the simulation software is capable of addressing the conditions required for the calculation. (Software with a well-mixed air assumption would not be able to apply this modeling approach).

***Update 11/9/20: This ruling is now applicable to LEED v4.1 BD+C and ID+C projects.

Campus Applicable
No
Internationally Applicable:
Yes
7/8/2017
LEED Interpretation
Inquiry:

ASHRAE 90.1-2010 mandatory requirement 8.4.2 Automatic Receptacle Control applies to 125 Volt receptacles in private offices, open offices, and computer classrooms. Are there any cases where exceptions to these mandatory requirements will be allowed?

Ruling:

The project team is requesting clarification regarding how to model spaces where mandatory ASHRAE 90.1 receptacle controls are not implemented. Projects using one of the following two compliance paths are exempt from the receptacle control requirements:

1. Path 1: Projects Using Option 1. Whole Building Energy Simulation may model a penalty in the Proposed model for the spaces where mandatory ASHRAE 90.1 receptacle controls are not implemented. The following modeling requirements apply:
• The receptacle power density modeled for these spaces shall be the greater of 0.75 Watts per square foot (8.1 Watts per square meter) or the design coincident peak receptacle power density (if known).
• The receptacle schedule modeled in the Baseline for these spaces shall have a minimum Equivalent Full Load Hours of operation no less than:
o The ASHRAE 90.1-2010 User’s Manual default schedule for office occupancy (2,920 Equivalent Full Load Hours per year)
OR
o 120% of the occupied hours of operation for the facility
OR
o Detailed justification shall be provided supporting an alternate schedule.

• The Proposed model shall include either a 20% increase in the receptacle power density for these spaces OR a 20% increase in the scheduled receptacle Equivalent Full Load Hours of Operation versus the Baseline model.

2. Path 2: Projects must demonstrate that the project has implemented efficiency measures that will achieve an equal or greater reduction in receptacle energy consumption, and will persist for a similar timeframe to those achieved by ASHRAE 90.1-2010 Section 8.4.2. It is recommended that a Credit Interpretation Request be submitted when pursuing this approach. The project must provide documentation regarding the receptacle equipment controls that will be implemented for the project; and must provide justification supporting the claim that the savings over the life of the efficiency measure will be similar to those anticipated for a project compliant with Section 90.1-2010 Section 8.4.2. Note: The baseline and proposed receptacle energy consumption for these spaces must be modeled identically if using this approach; the project is not eligible for any further receptacle savings in these spaces using the Exceptional Calculation Method.

Update 11/9/20:
Where ASHRAE 90.1 receptacle controls are not implemented in accordance with Section 8.4.2 mandatory requirements, LEED v4.1 projects may apply either Path 1 or Path 2, subject to the following requirements for Path 1:
• Path 1: LEED v4.1 projects Using the Appendix G Performance Rating Method may model a penalty in the energy model. The following modeling requirements apply:
o The Proposed receptacle power density modeled for these spaces shall be the greater of 0.75 Watts per square foot (8.1 Watts per square meter) or the design coincident peak receptacle power density (if known)
o The receptacle schedule modeled in the Proposed design for these spaces shall have a minimum Equivalent Full Load Hours of operation no less than: the ASHRAE 90.1-2016 User’s Manual default schedule for office occupancy (2,920 Equivalent Full Load Hours per year); or 120% of the occupied hours of operation for the facility; or detailed justification shall be provided supporting an alternate schedule.
o The Baseline model shall include either a 20% decrease in the receptacle power density for these spaces OR a 20% decrease in the scheduled receptacle Equivalent Full Load Hours of Operation versus the Proposed model.

Campus Applicable
No
Internationally Applicable:
Yes
4/9/2021
LEED Interpretation
Inquiry:

Our project is subject to ASHRAE 90.1-2019 for code compliance. ASHRAE 90.1-2019 Appendix G is very similar to ASHRAE 90.1-2016 Appendix G, with minor addenda between versions of the standard.

Can our project apply ASHRAE 90.1-2019 Appendix G in lieu of ASHRAE 90.1-2016 Appendix G? The Building Performance Factors referenced would be those published in ASHRAE 90.1-2016 Section 4.2.1.1 (e.g. the less stringent Building Performance Factors associated with the earlier version of the standard).

Ruling:

Yes, the project may apply ASHRAE 90.1-2019 Appendix G in lieu of ASHRAE 90.1-2016 Appendix G. The Building Performance Factors referenced shall be the less stringent Building Performance Factors from ASHRAE 90.1-2016 Section 4.2.1.1.

Note: For Unfinished spaces and systems, where ASHRAE 90.1-2019 Appendix G Table G3.1 Proposed Building Performance references ASHRAE 90.1 Sections 5 through 9 requirements, the corresponding references from ASHRAE 90.1-2016 Sections 5 through 9 shall be referenced in the model.

Campus Applicable
No
Internationally Applicable:
No
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.

LEEDuser expert

Marcus Sheffer

7group / Energy Opportunities
LEED Fellow

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.

Intent

To promote resilience and reduce the environmental and economic harms of excessive energy use and greenhouse gas emissions that disproportionately impact frontline communities by achieving a minimum level of energy efficiency for the building and its systems.

Requirements

Comply with ANSI/ASHRAE/IESNA Standard 90.1–2016, with errata or a USGBC-approved equivalent standard.

ASHRAE 90.1-2016 Compliance pathways in Section 4.2.1.1 include compliance with all mandatory provisions, and compliance with one of the following:

  • Prescriptive provisions of Sections 5 through 10
  • Section 11 Energy Cost Budget Method
  • Normative Appendix G Performance Rating Method. When using Appendix G, the Performance Cost Index (PCI) shall be less than or equal to the Performance Cost Index Target (PCIt) in accordance with the methodology provided in Section 4.2.1.1. Document the PCI, PCIt, and percentage improvement using metrics of cost or greenhouse gas (GHG) emissions.
  • Exception to Mandatory Measures requirements: For ASHRAE 90.1-2016 mandatory provisions where the Appendix G Performance Rating Method provides a methodology for demonstrating savings between the Proposed Building Performance (PBP) and the Baseline Building Performance (BBP), projects may model the Proposed Building Performance as designed in lieu of compliance with the mandatory provisions.
  • Exceptional Calculations modeled in accordance with Section G2.5 may be modeled to document minimum prerequisite compliance.
  • Only on-site or on-campus renewable energy that meets ASHRAE Standard 90.1-2016 Section G 2.4.1 requirements for on-site renewable energy may be used to meet ASHRAE Standard 90.1-2016 performance requirements.

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.

LEEDuser expert

Marcus Sheffer

7group / Energy Opportunities
LEED Fellow

See all LEEDuser forum discussions about this credit » Unsubscribe from discussions about NC-v4.1 EAp2