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XX%
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LEEDuser expert
Dylan Connelly
Integral Group
Mechanical Engineer
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Requirements
Case 1. Mechanically ventilated spaces
Option 1. ASHRAE standard 62.1-2007 or non-U.S. equivalent
Increase breathing zone outdoor air ventilation rates to all occupied spaces by at least 30% above the minimum rates required by ASHRAE Standard 62.1-2007 (with errata but without addenda1) as determined by IEQ Prerequisite 1: Minimum Indoor Air Quality Performance. Projects outside the U.S. may use a local equivalent to ASHRAE Standard 62.1-2007, if the same is used for IEQ Prerequisite 1: Minimum Indoor Air Quality Performance. OROption 2. CEN Standard EN 15251: 2007
Projects outside the U.S. may earn this credit by increasing breathing zone outdoor air ventilation rates to all occupied spaces by at least 30% above the minimum rates required by Annex B of Comité Européen de Normalisation (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, as determined by IEQ Prerequisite 1: Minimum Indoor Air Quality Performance,Case 2. Naturally ventilated spaces
Determine whether natural ventilation is an effective strategy for the project by following the flow diagram process in Figure 2.8 of the Chartered Institution of Building Services Engineers (CIBSE) Applications Manual 10: 2005, Natural Ventilation in Non-domestic Buildings. [Latin America ACP: Engineered Natural Ventilation Systems]AND
Option 1. CIBSE or non-U.S. equivalent
Show that the natural ventilation systems design meets the recommendations set forth in the CIBSE manuals appropriate to the project space.Path 1
Use CIBSE Applications Manual 10: 2005, Natural Ventilation in Non-domestic Buildings. Projects outside the U.S. may use a local equivalent.Path 2
Use CIBSE AM 13:2000, Mixed Mode Ventilation. Projects outside the U.S. may use a local equivalent.OR
Option 2. Airflow Model
Use a macroscopic, multizone, analytic model to predict that room-by-room airflows will effectively naturally ventilate, defined as providing the minimum ventilation rates required by ASHRAE Standard 62.1-2007 section 6 (with errata but without addenda), at least 90% of occupied spaces. Projects outside the U.S. may use Annex B of Comité Européen de Normalisation (CEN) Standard EN 15251: 2007, or a local equivalent to section 6 of ASHRAE Standard 62.1-2007 to define the minimum ventilation rates.Alternative Compliance Paths (ACPs)
Latin America ACP: Engineered Natural Ventilation Systems
Projects in Latin America may follow the Verification Protocol for Engineered Natural Ventilation Systems in Equatorial Climates and receive a design review and approval from the Colombian Professional Association of Air-conditioning, Ventilation and Refrigeration (ACAIRE). See all forum discussions about this credit »What does it cost?
Cost estimates for this credit
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Does each individual zone need a 30% increase in ventilation, or can a weighted average be used for the building?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.) |
Do spaces which are not regularly occupied require increased ventilation?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.) |
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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Requirements
Case 1. Mechanically ventilated spaces
Option 1. ASHRAE standard 62.1-2007 or non-U.S. equivalent
Increase breathing zone outdoor air ventilation rates to all occupied spaces by at least 30% above the minimum rates required by ASHRAE Standard 62.1-2007 (with errata but without addenda1) as determined by IEQ Prerequisite 1: Minimum Indoor Air Quality Performance. Projects outside the U.S. may use a local equivalent to ASHRAE Standard 62.1-2007, if the same is used for IEQ Prerequisite 1: Minimum Indoor Air Quality Performance. OROption 2. CEN Standard EN 15251: 2007
Projects outside the U.S. may earn this credit by increasing breathing zone outdoor air ventilation rates to all occupied spaces by at least 30% above the minimum rates required by Annex B of Comité Européen de Normalisation (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, as determined by IEQ Prerequisite 1: Minimum Indoor Air Quality Performance,Case 2. Naturally ventilated spaces
Determine whether natural ventilation is an effective strategy for the project by following the flow diagram process in Figure 2.8 of the Chartered Institution of Building Services Engineers (CIBSE) Applications Manual 10: 2005, Natural Ventilation in Non-domestic Buildings. [Latin America ACP: Engineered Natural Ventilation Systems]AND
Option 1. CIBSE or non-U.S. equivalent
Show that the natural ventilation systems design meets the recommendations set forth in the CIBSE manuals appropriate to the project space.Path 1
Use CIBSE Applications Manual 10: 2005, Natural Ventilation in Non-domestic Buildings. Projects outside the U.S. may use a local equivalent.Path 2
Use CIBSE AM 13:2000, Mixed Mode Ventilation. Projects outside the U.S. may use a local equivalent.OR
Option 2. Airflow Model
Use a macroscopic, multizone, analytic model to predict that room-by-room airflows will effectively naturally ventilate, defined as providing the minimum ventilation rates required by ASHRAE Standard 62.1-2007 section 6 (with errata but without addenda), at least 90% of occupied spaces. Projects outside the U.S. may use Annex B of Comité Européen de Normalisation (CEN) Standard EN 15251: 2007, or a local equivalent to section 6 of ASHRAE Standard 62.1-2007 to define the minimum ventilation rates.Alternative Compliance Paths (ACPs)
Latin America ACP: Engineered Natural Ventilation Systems
Projects in Latin America may follow the Verification Protocol for Engineered Natural Ventilation Systems in Equatorial Climates and receive a design review and approval from the Colombian Professional Association of Air-conditioning, Ventilation and Refrigeration (ACAIRE).XX%
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- Examples of actual submissions from certified LEED projects.
Does each individual zone need a 30% increase in ventilation, or can a weighted average be used for the building?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.) |
Do spaces which are not regularly occupied require increased ventilation?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.) |
LEEDuser expert
Dylan Connelly
Integral Group
Mechanical Engineer
