Technical Clarification
Thermal comfort and 'Shell & Core' spaces
Technical Clarification Number
IEQ9-T-RC1-0362
Guidance
2013-07-22
The following guidance is provided for spaces delivered as ‘Shell & Core’, as defined in the Green Star SA Retail Centres v1 Technical Manual.
The thermal comfort within a mechanically ventilated space is highly influenced by the design of the HVAC system within the space. Where a mechanically ventilated space is not provided with a complete HVAC system, as evidenced through the provision of a fully documented design within the tender documentation (Design rating) or as installed As Built documentation and commissioning reports (As Built rating), compliance with the Credit Criteria cannot be demonstrated.
Technical Clarification
HVAC plant operating schedules
Technical Clarification Number
IEQ9-T-RC1-0597
Guidance
2012-11-05
Should operating schedules of HVAC equipment be used as part of the energy performance or thermal comfort strategy , e.g. night flushing or early start-up of HVAC plant, the actual HVAC plant operating schedules for the related equipment as supported by tender documentation (Design) or commissioning data (As Built) may be used for the Ene-1 actual building modelling and IEQ-9 credit modelling.
Please note that if any overrides over timer based controls are included in the system (e.g. CO2 or temperature overrides) these should be accounted for accurately or assumptions conservatively justified – alternatively the HVAC plant operating schedules in the energy modelling protocol should be used.
Note that for the Ene-1 notional building, the HVAC plant operating schedules in the energy modelling protocol should be used.
Technical Clarification
Revised documentation requirement - Thermal comfort report
Technical Clarification Number
IEQ9-T-RC1-0387
Guidance
2012-07-26
The following updates the documentation requirements of the 'Thermal comfort report' required for both Design and As Built submission as per Page 89 of the Green Star SA - Retail Centre v1 Technical Manual. This update is applicable to naturally ventilated buildings, mechanically ventilated spaces and mixed-mode spaces:
Thermal comfort report prepared by a suitably qualified professional that describes how the credit criteria have been met by -
• Describing the HVAC system (where applicable) and passive design strategies used to achieve thermal comfort;
• Confirming which thermal comfort methodology has been used (i.e. ASHRAE 55-2004 Acceptability Limits or ISO7730 PMV values), with justification for the selection based on the Credit Criteria;
• Describing the software package used for determining thermal comfort levels;
• Describing the weather data used and its source, demonstrating that it complies with the weather data requirements of the Additional Guidance;
• Providing marked-up plan drawings clearly showing the zones modelled for thermal comfort and that no perimeter zone exceeds 4m in depth;
• Providing a tabulated summary of all zones modelled, indicating the area of each and confirming all of the UA has been included in the analysis;
• Confirming the occupancy schedule and total number of hours assessed for thermal comfort;
• Confirming that all modelling inputs are in exact accordance with the modelling presented in Ene-1 Greenhouse Gas Emissions;
Additionally where ASHRAE 55-2004 Acceptability Limits methodology used:
• Confirming all spaces assessed are provided with openable windows, and not provided with mechanical cooling systems;
• Providing a table of the mean monthly temperatures and resulting acceptability range;
• Providing a summary table of all zones assessed for thermal comfort and the hours below, within and above the Acceptability Limits of operative temperatures, clearly demonstrating compliance with the Credit Criteria.
Additionally where PMV ISO7730 methodology used;
• Confirming that the CLO and MET values used are in accordance with the Additional Guidance;
• Demonstrating that the air velocity value selected is justified for the actual system design.
• Providing a summary table of all zones assessed for thermal comfort and the hours below, within and above the stipulated PMV levels, clearly demonstrating compliance with the Credit Criteria.
Erratum
Green Star SA - Retail Centre v1 Technical Manual: Page 88
Erratum Number
IEQ9-E-RC1-0121
Guidance
2011-01-06
Credit Criteria, Deemed-to-satisfy, second bullet point, add a second second-tier bullet point (designated with a dash in the Technical Manual) with the statement "All mall area must have fresh air & ventilation provided as a minimum in accordance with SANS 10400-O (for naturally ventilated or mechanically ventilated spaces)."
Erratum
Green Star SA - Retail Centre v1 Technical Manual: Page 88
Erratum Number
IEQ9-E-RC1-0163
Guidance
2011-01-06
Credit Criteria, Deemed-to-satisfy, first bullet point, delete the words "For a fully mechanically air conditioned building".
Erratum
Green Star SA - Retail Centre v1 Technical Manual: Page 87
Erratum Number
IEQ9-E-RC1-0164
Guidance
2011-01-06
Credit Criteria, Second point, delete the text of the bullet point "The deemed to satisfy conditions for the mall spaces within the nominated are met." and replace with "The credit criteria above for the first point are met for all mall spaces within the nominated area."
Erratum
Green Star SA - Retail Centre v1 Technical Manual: Page 88
Erratum Number
IEQ9-E-RC1-0165
Guidance
2011-01-06
Credit Criteria, Deemed-to-satisfy, first bullet point, delete the statement "Relative Humidity within range of 40% to 60%;" and replace with "Fresh air & ventilation are provided as a minimum in accordance with SANS 10400-O (for naturally ventilated or mechanically ventilated spaces);"
Credit Interpretation Request
PMV assessment at expected maximum and minimum historical ambient temperatures
Credit Interpretation Request Number
IEQ9-C-RC1-0113
Ruling
2010-11-10
The Credit Interpretation Request (CIR) seeking to assess the Predicted Mean Vote (PMV) values for compliance to the credit criteria at the expected maximum summer and minimum winter ambient temperatures only, based on historical metrological data for the site, is denied.
The CIR Review Panel notes that the PMV measure of thermal comfort is calculated from a range of variables including occupant metabolic rate, occupant clothing levels, radiant surface temperature, zone air temperature, zone humidity and zone air velocity. Many of these variables are constantly changing within the occupied zones of a building due to the combination of external climatic influences (e.g. ambient temperature, solar radiation, humidity etc.), internal loads (sensible and latent) and the response of the building’s HVAC system to these influences to maintain air temperature within the control band and set points. As such, it is possible that although zone air temperature can be maintained within the target control band and set points at the proposed extreme ambient conditions, the influence of the other contributing variables may cause PMV results to exceed the acceptable range prescribed in the credit criteria. This may occur at any occupied hour of the year and is not limited to the worst case ambient conditions (historical or otherwise). Hence hourly simulation is required to assess how many hours of the total occupied hours of the year do the PMV results exceed the acceptable range as prescribed in the credit criteria to determine compliance with the credit criteria.
Technical Clarification
Definitions - "occupied hours”, “standard hours of occupancy” and "standard working hours"
Technical Clarification Number
IEQ9-T-RC1-0110
Guidance
2010-11-02
For the purpose of this credit, “occupied hours”, “standard hours of occupancy” and "standard working hours" are defined as equivalent and equal to the operational profile of the ‘HVAC plant’ as detailed in the applicable Energy Calculator & Modelling Protocol Guide. This definition is applicable to both mechanically ventilated spaces and naturally ventilated spaces (irrespective of the inclusion of HVAC plant or not). Please note these definitions do not amend the ‘Occupancy’ profiles as defined in the applicable Energy Calculator & Modelling Protocol Guide.
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