energy star multifamily high rise program introduction to the performance path july 2011
TRANSCRIPT
ENERGY STARMultifamily High Rise Program
Introduction to the Performance Path
July 2011
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Performance Path Components
• Prerequisites
• Performance Target
• Simulation Guidelines
• Performance Path Calculator
• Modeling Checklist
• Testing and Verification (T&V)
• Benchmarking using Portfolio Manager
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Prerequisites
• Appliances
• Heating and Cooling Equipment & Distribution
• Envelope
• Garages and Sidewalks
• Ventilation and Infiltration
• Domestic Water Heating
• Lighting
• Pump Motor Efficiency
Appliances
• When provided in common areas and/or apartments, refrigerators, dishwashers, clothes washers, ceiling fans, exhaust fans and vending machines must be ENERGY STAR qualified.
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Heating and Cooling Equipment – ASHRAE Mandatory Provisions
• The heating and cooling systems must comply with ASHRAE 90.1-2007, Section 6.4.
• Ex. “Independent heating and cooling thermostatic controls (if any) are interlocked to prevent crossover of set points.”
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Heating and Cooling Equipment - Sizing
• Load sizing calculations must reflect the design. The installed capacity cannot exceed design by more than 20%, except when smaller sizes are not available.
• Example: If design results in a 12,100 Btuh air conditioning system, 14,520 Btuh is the most that can be installed. If 18,000 Btuh is the smallest size available, it’s permitted.
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Heating and Cooling Equipment – Load Calculation
• Heating and cooling loads must be calculated and equipment capacity must be selected according to the latest editions of ACCA Manual J & S, ASHRAE 2009 Handbook of Fundamentals, or equivalent procedure.
• Indoor temperatures must be 70°F for heating and 75°F for cooling.
• Outdoor temperatures must be the 1.0% and 99.0% design temperatures, as published by the ASHRAE Handbook of Fundamentals.
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Heating and Cooling Equipment
• EPA recommends, but does not require, that heating and cooling equipment be ENERGY STAR qualified.
• Atmospherically vented gas furnaces and boilers shall not be specified.
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Heating and Cooling Distribution – Ducted Forced Air System Design
• For in-unit ducted forced air distribution systems, perform design calculations (using ACCA Manuals J and D, the ASHRAE Handbook of Fundamentals, or an equivalent procedure) and install ducts according to design.
• Flex duct shall follow the Sheet Metal and Air Conditioning Contractors’ (SMACNA) installation standards for flex ducts.
• Bedrooms must be pressure-balanced using any combination of transfer grills, jump ducts, dedicated return ducts, and/or undercut doors.
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Heating and Cooling Distribution – Insulation
• Heating and cooling supply and return ductwork must be insulated to a minimum R-6 in unconditioned space.
• Piping carrying fluid or steam with temperatures less than 60°F or greater than 105°F, must have a minimum of 1” of insulation. Pipes over 1.5” in diameter carrying fluid or steam with temperatures less than 60°F or greater than 105°F, must have a minimum of 1.5” of insulation.
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Heating and Cooling Distribution –Sealing
• Heating and cooling ductwork must be sealed at all transverse joints and connections, including ductwork connections through drywall or other finish materials, using UL-181 compliant methods and materials.
• Ductwork and piping must be inspected before access is covered up to ensure proper sealing and insulation. Sampling procedures are described in the T&V Protocols, available on the MFHR website.
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Heating and Cooling Distribution – Total Duct Leakage
• Total duct leakage for in-unit ducted forced air systems shall be:
≤6 CFM25 per 100 ft2 of conditioned floor area for units 1200 ft2 and greater.
≤8 CFM25 per 100 ft2 of conditioned floor area for units less than 1200 ft2.
• Sampling procedures described in the T&V Protocols, available on the MFHR website.
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Heating and Cooling Distribution - Controls
• Terminal distribution equipment serving an apartment shall be controlled by a thermostat within the same apartment.
• For hydronic distribution systems, terminal heating and cooling distribution equipment must be separated from the riser or distribution loop by a control valve or terminal distribution pump, so that heated or cooled fluid is not delivered to the apartment distribution equipment when there is no call from the apartment thermostats.
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Heating and Cooling Distribution – Outdoor air dampers
• For systems designed with outdoor air supplied to the heating, cooling, or ventilation distribution system, provide motorized dampers that will automatically shut when systems or spaces are not in use.
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Heating and Cooling Distribution – Hydronic Design
• For hydronic distribution systems, all supply/return headers must be designed in a “reverse return” configuration (i.e. first riser supplied is the last returned, etc.) and/or sized based on a water velocity of less than 4 ft/s.
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Heating and Cooling Distribution – Hydronic Design, cont’d
• Total pressure drop of terminal unit branch piping and fittings between a supply and return riser must be significantly greater than the total pressure drop from the top to the bottom of these risers.
• Calculations and assumptions for sizing circulating pumps must meet Chapter 43 of the ASHRAE Handbook, HVAC Systems and Equipment or equivalent industry accepted standard.
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Envelope – Air Barrier
• The building plans shall demonstrate a continuous, unbroken air barrier separating the conditioned space of the building from the: – The exterior,– unconditioned spaces within the building,– commercial spaces,– mechanical rooms vented with unconditioned air, – mechanical chases opening to unconditioned spaces,– elevator shafts, and – garages or other vehicle/equipment storage facilities.
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Envelope - Infiltration
• Apartments shall be sealed to reduce air exchange between the apartment and exterior as well as the apartment and adjacent spaces.
• A maximum air leakage rate of 0.30 CFM50 per square feet of enclosure is allowed.
• Sampling procedures are described in the T&V Protocols. Specific leakage paths are identified in the T&V Worksheets.
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Envelope – U-values
• The envelope components must comply with ASHRAE 90.1-2007, Section 5.4.
• Ex.“Loose fill insulation is not used in attic roof spaces when the ceiling slope is more than 3/12.”
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Envelope – U-values, continued
• U-value determinations must follow ASHRAE 90.1-2007, Appendix A.– 2x4, 16” oc, wood frame, R-13 FG, U-0.089– 2x4, 16” oc, steel-frame, R-13 FG, U-0.124
• An area weighted average of the U-values of the wall and floor perimeter assemblies is acceptable for use in the energy model.
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Envelope – Walls & Windows
• RESNET-defined Grade I insulation installation or Grade II if combined with continuous insulation (≥R-3 in CZ 1-4 and ≥R-5 in CZ 5-8).
• For steel-framed and metal buildings, continuous exterior insulation is required.
• For masonry buildings with metal framing, continuous interior or exterior insulation is required.
• Specified windows must be low-e and double- or triple-pane.
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Envelope – Vestibules & AC sleeves
• When required by local building code, entranceways shall be designed with vestibules with weather-stripping hard-fastened to the door or frame.
• Insulated covers (R-7 or higher) for through-wall AC units must be provided by the building for use during the heating season or when AC units are not installed.
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Garages and Sidewalks
• Attached garages shall be fully compartmentalized from the rest of the building through air sealing.
• All pipe and conduit penetrations shall be sealed with material compatible with the surface and resilient to temperature fluctuations.
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Garages and Sidewalks
• Garages shall not be heated for comfort or to prevent pipes from freezing. Piping design and layout shall locate piping within conditioned spaces or grouped and properly insulated to prevent freezing.
• Radiant heating, either wall or ceiling-mounted or within the garage floor (or sidewalks) may be used to prevent ice formation on the ground as a safety feature only and must comply with ASHRAE 90.1-2007 Section 6.4.3.8.
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Ventilation – ASHRAE 62 requirements
• Common area ventilation systems shall be designed and tested to satisfy minimum requirements of ASHRAE 62.1-2007.
• Apartment ventilation systems shall be designed and tested to satisfy minimum requirements of ASHRAE 62.2-2007 based upon the anticipated occupancy.
• Providing dedicated outdoor air to each unit is recommended, but not currently required.
• Kitchen exhaust must be vented to the outside.
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Ventilation – Duct sealing & Leakage
• Ventilation system ductwork must be sealed at all transverse joints and connections including boot to wall/ceiling connections through drywall using UL-181 compliant materials and methods.
• Ductwork penetrations must be sealed at the roof curb to prevent air leakage through the duct system and/or the building envelope.
• Central exhaust systems must be tested for duct leakage, which cannot exceed 10 CFM50 per floor per shaft. See T&V Protocols for details.
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Domestic Water Heating
• Domestic water heating systems must comply with ASHRAE 90.1-2007, Section 7.4.
• Atmospherically vented gas water heaters, tankless coils and side-arm water heaters shall not be specified.
• If storage is provided, the maximum storage tank capacity shall be specified based on occupancy.
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Domestic Water Heating – Temperature and Pressure
• Self-contained or electronic mixing valves shall be used to control hot water temperature for central domestic water heating systems.
• The temperature of the stored hot water shall be just sufficient to deliver water to apartments within a temperature range of 120-125°F.
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Domestic Water Heating – Low Flow
• The average flow rate for all faucets must be ≤ 2.0 gallons per minute.
• All showerheads must be WaterSense labeled.• All tank-type toilets must be WaterSense
labeled.
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Lighting
• Lighting must comply with ASHRAE 90.1-2007, Section 9.4.
• 80% of installed light fixtures must be ENERGY STAR qualified or have ENERGY STAR qualified lamps (bulbs) installed.
• Lighting must be designed to meet light levels (footcandles) by space type as recommended by the Illumination Engineering Society (IESNA) Lighting Handbook, 9th edition.
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Lighting – Footcandles
ASHRAE Space Type
Lighting Power
Densities (W/ft2)
Recommended Light Levels
(Weighted Avg. Footcandles)
ASHRAE Space Type
Lighting Power
Densities (W/ft2)
Recommended Light Levels
(Weighted Avg. Footcandles)
Apartments 1.1 16 Stairs - Active 0.6 15
Storage, active 0.8 20 Restroom 0.9 12
Storage, inactive
0.3 8 Office 1.1 35
Food Preparation
1.2 40Conference/meeting/multipurpose
1.3 30
Dining Area - For Family Dining
2.1 23Electrical/Mechanical
1.5 30
Lobby 1.3 16 Workshop 1.9 50
Corridor/Transition
0.5 10 Parking garage 0.2 7
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Lighting – Common Areas
• All non-apartment spaces, except those intended for 24-hour operation or where automatic shutoff would endanger the safety of occupants, must have occupancy sensors or automatic bi-level lighting controls.
• Total installed lighting power for the combined common spaces should not exceed ASHRAE 90.1-2007 allowances for those combined spaces by more than 20%.
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Lighting – Power Densities (LPDs)
ASHRAE Space Type
Lighting Power
Densities (W/ft2)
Recommended Light Levels
(Weighted Avg. Footcandles)
ASHRAE Space Type
Lighting Power
Densities (W/ft2)
Recommended Light Levels
(Weighted Avg. Footcandles)
Apartments 1.1 16 Stairs - Active 0.6 15
Storage, active 0.8 20 Restroom 0.9 12
Storage, inactive
0.3 8 Office 1.1 35
Food Preparation
1.2 40Conference/meeting/multipurpose
1.3 30
Dining Area - For Family Dining
2.1 23Electrical/Mechanical
1.5 30
Lobby 1.3 16 Workshop 1.9 50
Corridor/Transition
0.5 10 Parking garage 0.2 7
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Lighting – Calculations
• The requirement of ASHRAE 90.1-2007, Section 9.1.4a, that light fixtures MUST be modeled with the maximum labeled wattage of the fixture is not required.
• Example: A fixture with a 13 W screw-in CFL can be modeled as 13 W, plus any associated ballast power. See Appendix B of Performance Path for suggested ballast power.
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Lighting – Exterior
• 80% of outdoor lighting fixtures must be ENERGY STAR qualified or have ENERGY STAR qualified lamps installed.
• Fixtures must include automatic switching on timers or photocell controls except fixtures intended for 24-hour operation, required for security, or located on apartment balconies.
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Lighting – Exit Signs
• All exit signs must be specified as LED (not to exceed 5W per face) or photo-luminescent and must conform to local building code; fixtures located above stairwell doors and other forms of egress must contain a battery back-up feature.
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Pump Motor Efficiency
• All three-phase pump motors 1 horse-power or larger shall meet or exceed efficiency standards for NEMA Premium™ motors, where available.
• Many motors are NEMA labeled and this label alone, does not ensure that a motor is energy-efficient. This requirement refers specifically to the NEMA Premium energy efficient motors program.
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Metering
• The commercial/retail parts of the building shall be separately metered or sub-metered for electricity, gas, fuel oil, water, and steam, where applicable.
• The building owner must provide a signed release for the common area/whole-building utility meters and must secure signed utility bill releases from individual apartment occupants to allow for benchmarking or obtain whole-building consumption data from their local utility.
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Performance Path Components
Prerequisites
• Performance Target
• Simulation Guidelines
• Performance Path Calculator
• Modeling Checklist
• Testing and Verification (T&V)
• Benchmarking using Portfolio Manager
Performance Target
• ASHRAE 90.1 Standards provide the minimum requirements for the energy-efficient design of commercial buildings, including high rise multifamily buildings
• An energy model of the Proposed Design is compared to one of a Baseline design that meets ASHRAE 90.1-2007, and energy cost savings are determined
• Performance metric, not a predictor of actual energy cost savings
• 15% energy cost savings over ASHRAE Standard 90.1-2007 needed for ENERGY STAR
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How do you create the models?
• Unlike the New Homes program, REM/Rate is not used.
• Appendix G lists the requirements of software approved for the program (ex. eQUEST, DOE-2, HAP, Energy Gauge, EnergyPlus, etc).
• Appendix G and the User’s Manual of the 90.1-2007 Standard provide some protocols for creating these energy models.
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Simulation Guidelines
• The Simulation Guidelines were developed to:– Establish modeling protocols for measures that
ASHRAE 90.1 leaves to the ‘rating authority’ to decide– Facilitate consistent modeling of baseline components
not mentioned in Appendix G– Facilitate consistent modeling among modelers– Ensure that modeling results drive the design process
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Performance Path Calculator
• Excel-based worksheets designed to provide consistency among energy modelers by providing the exact calculations described by the Simulation Guidelines.
• Provides consistent formatting for reporting the results to the EPA.
• Reporting Summary worksheet must be submitted and approved twice, once prior to construction and once after construction is complete.
Energy Modeling QC Checklist
• Optional checklist developed to provide energy modelers with a quality control checklist of simulation requirements for use prior to submission of results.
• Draws attention to commonly missed requirements or those that may be different in commercial or single family energy models.
• The checklist is organized according to eQUEST software, and references specific output reports and user-input fields. It can be applied to other software.
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Testing and Verification
• Buildings following the Performance Path must follow the Testing and Verification Protocols.
• These protocols are the mandatory requirements for the inspection, testing and verification of components related to the building’s energy performance.
• The intent of the protocols is to verify that – the construction documents & final building include all
Prerequisites.– measures used to achieve the Performance levels
predicted by the model have been installed and perform as modeled.
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Testing and Verification
• Changes to the initial design noted during inspections must be reflected in a revised model and submitted as the As-Built model.
• The As-Built model must meet the 15% Performance Target to earn the ENERGY STAR.
• The Testing and Verification worksheets and Photo Template must be submitted as they document the results of all mandatory testing and verification.
• A separate webinar on the T&V Protocols and another on how to document them, are available on the EPA MFHR website.
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Performance Path Components
PrerequisitesPerformance TargetSimulation GuidelinesPerformance Path CalculatorModeling ChecklistTesting and Verification (T&V)
• Benchmarking using Portfolio Manager
Performance Path Steps
• Apply to Program; become a Partner• Meet Prerequisites• Conduct Energy Modeling, review plans• Submit Reporting Summary and T&V worksheets• Build according to Design• Conduct Testing and Verification• Update model, resubmit worksheets and photo
template to EPA• Earn the ENERGY STAR • Benchmark for two years
